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UNITED STATES OF AMERICA.
FERTILIZERS
FERTILIZERS
THE SOURCE, CHARACTER AND COMPOSITION OF
NATURAL, HOME-MADE AND MANUFACTURED FERTILIZERS;
AND SUGGESTIONS AS TO THEIR
USE FOR DIFFERENT CROPS AND CONDITIONS
v
/ 135'6
EDWARD B. VOORHEES, A.M.
Director of the New Jersey Agricultural Experiment Stations, and
Professor of Agriculture in Rutgers College
New Vork
THE MACMILLAN COMPANY
LONDON: MACMILLAN & CO., Lrp.
1898
All rights reserved
1897!
COPYRIGHT, 1898
By EDWARD B. VOORHEES
Mount Pleasant Priniery
J. Horace McFarland Company
Harrisburg, Pa.
CLOUT Sep. 30 ha ts
PREFACE
THERE is no question as to the desirability of
the use of commercial fertilizers on most farms,
though the methods now generally practiced are such
as to indicate the very great need of a better under-
standing of what the functions of a fertilizer are,
of the terms used to express their composition and
value, of the kind that shall be used, and the time
and method of application for the different crops
under the varying conditions that exist.
In the preparation of this book, therefore, it has
been the aim of the author to point out the under-
lying principles and to discuss, in the light of our
present knowledge of the subject, some of the
important problems connected with the use of fer-
tilizer materials. The subject is a large one when
considered in all its bearings, and much must nec-
essarily be omitted in a book intended for the
general reader as well as the student.
The author- appreciates keenly his _ limitations,
owing to the lack of definite knowledge on many
vital points; yet it seems that at this time, when
(v)
vl PREFACE
the investigations of the experiment stations are
beginning to be regarded as important educational
factors, and when these institutions are more than
ever prepared to study the fundamental principles
which underlie the various processes involved in
plant nutrition, the practical man should have a
clear understanding of what is now known, in order
that he may be prepared to accept and use that
better knowledge which will undoubtedly be _ pro-
vided for him in the near future.
Kk Bee
New BRUNSWICK, N. J., September 20, 1898.
CONTENTS
CHAPTER I
THE NATURAL FERTILITY OF THE SOIL, AND SOURCES OF
LOSS OF THE ELEMENTS OF FERTILITY .....-0.2-2--0>
Soi1L FERTILITy—Chemical elements needed in plant
growth—Fertility as influenced by water, climate and
season—The influence of physical character of soil—
Location of soil qualifies the term “fertility ” — Practical
fertility is usable potential fertility ..............-.eeeees
SourRcES oF NaTuRAL Loss or NITROGEN—Importance of
careful culture—Loss of nitrogen by drainage— Escape of
BEroren IGto the aAbLMOSPHEPO:5 oes sjic dsp dswas oe oe aid anes nds
THE NATURAL LOSS OF .THE MINERAL ELEMENTS— Losses
MueuLO MEChANiCal MCAS: ;ar,clarsseeiee aie alates Aa ayes wVee/Ses
ARTIFICIAL LOSSES OF FERTILITY—A comparison of the
prices received for the fertility elements in different
crops—Fertility content of cereals and vegetables-— Irra-
tional farm practice—Losses in ManureS.............eeees
CHAPTER II
THE FUNCTION OF MANURES AND FERTILIZERS, AND THE
NEED OF ARTIFICIAL FERTILIZERS .....2.....sss000-
THE ESSENTIAL ELEMENTS OF FERTILIZERS .......-. wisieieaie's
NATURAL MANURES AND ARTIFICIAL FERTILIZERS ...cesecess
(vii)
PAGES
1-20
2-7
7-8
8-12
12-14
14-20
21-37
21
22
Vill CONTENTS
PAGES
DIRECT AND INDIRECT EFFECT OF MANURES....cccccccescees 23
UNAVAILABLE AND AVAILABLE PLANT-FOOD ..... Shamruoa ues 24-26
DANGER OF LOSS FROM THE USE OF SOLUBLE PLANT-FOOD.. 26
THE USEFULNESS OF A FERTILIZER CONSTITUENT DOES NOT
DEPEND UPON ITs ORIGINAL SOURCE...... Stacie p's viniahawontt 27
Ust oF FERTILIZERS. 2.5.0.6. amtaaie s Sad aha deme Sees pm emee 28, 29
THE NEED OF ARTIFICIAL FERTILIZERS—The cost of produc-
tion per unit of income is increased—A greater demand for
special crops—Farm manures are inadequate—The growing
importance of fruit-growing............ i oh ane me oes Seno 30-35
WILL It Pay TO USE FERTILIZERS? ......... i Sate an ee eae ea 35-37
CHAPTER III
NITROGENOUS FERTILIZERS ....-..-0000. eima jedeintn st ateleteaate ~ B8-57
Waat Is MEANT BY FORM OF NITROGEN ? ....0ccccenscscecns 39
DRIED, WSDOOD sa. creche cclecsle clears cere siaeinls oratelerare sicher Goketae cyelbiisrerate 40, 41
DRIED MEAT OR MEAL, AZOTIN, AMMONITE, OR ANIMAL
EAT TIES sce apie armremie) nals mn a eniareirt Wen Meee «sie Sipand aincaia aera 41
IGOR MBAti. oes iacewes ceed wa elas ee cae waela cen nina enstd - 42
DRIED AND GROUND FISH, OR FISH GUANO...... aa Rtas acl 42
PWG CRAB cizvisin eles xiaiai uae w acaleintcungaceeeheis aeaaiarnae wa iat'y. bisidlald ape toners 43
PB AICA GTS |. o/o:35,0.0,0 a: 3 aieis e nimyviane aciasein eiaiats aie cena ene iata eat otals 43, 44
GARBAGE 'TANKAGE «'o. «<9,0s.cq cael cemnaee eee Sees ane 44
LOW-GRADE NITROGENOUS PRoDuUcTS—Leather meal— Wool
ged: We WASEO. sc.<d0ds «sce. nas oes eee diene aera 45
VEGETABLE NITROGENOUS PRODUcTS—Cotton-seed meal—
Linseed meal—Castor pomace..... PO Peer re tn whctesions 46
BATURAL AGUANOS sgh 4265s oe eeeiew nd ene wr disable! arson Batecieiete 47-49
AMMONIA CoMPOUNDS—Sulfate of ammonia........ oie wiateen 3 50, 51
NITRATE NITROGEN—Nitrate of soda..........-.-eee- seed 52
THE RELATIVE AVAILABILITY OF THE DIFFERENT FORMS OF
NITROGEN—Conditions which modify availability.......... 53-57
CONTENTS
CHAPTER IV
PHOSPHATES— THEIR SOURCES, COMPOSITION, AND RELA-
aR MUPEBSE RGIS N ie oe fe ow Vicks ws ae am lee 2S Sine e's ee ee
PHOSPHATE OF LIME, OR BONE PHOSPHATE—ANIMAL BONE—
Raw bone—Fine bone—Boiled and steamed bone—Bone
tankage—Other organic products—Bone-black, or animal
charcoal— Bone ash ............ PEE ee ee ee Ee
MINERAL PHOSPHATES—South Carolina rock phosphates—
Florida phosphates—Canadian apatite—Tennessee phos-
phate—Iron phosphate, or Thomas phosphate powder—
ees PUAMOR. ws 5. «sas Soaring sical a wieinin ook cia skied <a Sieraaios
PHOSPHATES AS SOURCES OF PHOSPHORIC ACID TO PLANTS—
The infiuence of source of phosphate upon availability—
Influence of fineness of division—The character of soil as
a factor influencing availability—Influence of kind of
ereop—General considerations. ....5.0scecessessnnepan esse nd
CHAPTER V
PirPHEPHOSPHATES—POTASH «4.6.06 ns deh wees cee eee
INSOnUEEE (PHOSPHORIC: ACID. <2 cae cles aiciesiee sietete ee sietete cntale
NOME E EHOSPHORIO! ACID ic, (6c o:<tole dies a/s'e sic winiecna om oi cisonte oie e
REVERTED PHOSPHORIC ACID
How SvuPERPHOSPHATES ARE MADE—The difference in the
superphosphates made from the different materials—Sol-
uble phosphoric acid identical chemically, from whatever
PERIORS AERIS | 5 a cota siccniahe 5, diene alana als atc a seme as
PHOSPHATES AND SUPERPHOSPHATES ARE NOT IDENTICAL...
DouBLE SUPERPHOSPHATES
eeeee eset esses esses e see es eee ee eees
CHEMICAL COMPOSITION OF SUPERPHOSPHATES— Well-made
superphosphates contain no free acid—Phosphoric acid
remains in the soil until taken out by plants...........
PotasH SAutTs—The importance of potash as a constituent
of fertilizers—Forms of potash—Kainit—Sylvinit—Muri-
ate of potash—High-grade sulfate of potash— Double
sulfate of potash and magnesia—Fixation of potash.....
59-66
66-71
71-77
78-98
78
79
80
80-83
83-87
87
88-91
92-98
x CONTENTS
CHAPTER VI
PAGES
MISCELLANEOUS FERTILIZING MATERIALS .....ceeeeee+- 99-123
TOBACCO STEMS AND STALES ...ccsccccseecesas S<mavel wees « 200, 102
CRUDE VIS CORAL . scncvasusnaies kueweexwasiciae * TS cvsasve 20J-103
WooL AND HAIR WASTE: «vex canes Vike hase eeaawe «nena eam 103
POULTRY AND PIGEON MANURES ........«. Pere 104
SEWAGE ..ii3 sacneiv oeku wen icteeans qgeeaenes hheus Shia e Gow 105
MUCK AND PRAPssccc0sbsccWeeneesces ce nic MOEN EN EWE aoa 106
KinG@ CRAB, MUSSELS AND LOBSTER SHELLS........... Saees 107
SEAWEED ys ccnuc kn davai anahhianas nde ts kwiad a sauaueete boast 108
Woop ASHES AND TAN-BARK ASHES .....ccc.cccccccsccccece 109-111
COAT; ASHES: . 605 ccavnes cdnacd Senne biuetes keenest eae ‘ 111
COTTONAHULL ASHES 526 s6nc 200% cobs Keeeen oct eh ben seuebe See 111
MAS ci camccGsteescaceeeb tees abees crews seek eae <aSapames 112
TOR i 5 hie a Sra eed ah aalet en sa cicen s onsid dan Dawelshidenaue ceoeieen 113-116
AGRICULTURAL SALT. ss .00'so0086sa000s fePwede ease fi cmamne 116
POWDER “WARPED ccecs sineactamises Necdnens aaeas sue demiewee eae 117
GREEN MANURES—“ Nitrogen gatherers” and “nitrogen con-
sumers ”—The most useful crops—Green manure crops that
consume the nitrogen in the soil ....cc<cdvastgscts veces 117-123
CHAPTER VII
PURCHASE OF WER TILIZERS 53 jx s'sd Sc cers ae Te eee wee 124-148
STANDARD HIGH-GRADE MATERIALS .......ccecscecncscscecs 125, 126
FERTILIZING MATERIALS VARIABLE IN COMPOSITION........ 126, 127
HIGH-GRADE AND LOW-GRADE FERTILIZERS—The “unit”
basis of purchase—The “ton” basis of purchase—The
necessity of a guarantee— Laws alone do not fully protect—
Method of statement of guarantee sometimes misleading—
Discussion of guarantees—The advantages and disadvan-
tages of purchasing raw materials and mixed fertilizers... 127-141
HoME MixtTuRES— Formulas—A low-grade fertilizer— The cost
of handling *make-weight” ...:..s0%.steementoebene beatae 141-147
GENERAL ADVIGE .é...<< 44544 0encud. ccesmeenseeend] eee. eee 147-148
CONTENTS Xl
CHAPTER VIII
PAGES
CHEMICAL ANALYSES OF FERTILIZERS .........e000. .--- 149-166
THr INTERPRETATION OF AN ANALYSIS.... ccc cccccccccccecs 149-152
THE AGRICULTURAL VALUE OF A FERTILIZER.........0.000. 152-153
THE COMMERCIAL VALUE OF A FERTILIZER—Schedule of
trade values adopted by experiment stations for 1898 ...... 153-162
CALOULATION OF COMMERCIAL, VALUES. ....0.sseccece aes. cae 162-164
THE UNIFORMITY OF MANUFACTURED BRANDS.....c.. cee cece 164-166
CHAPTER IX
Weraovs OF Ust OF FERTILIZERS ©... cos cscsvctvugeaes 167-190
CONDITIONS WHIcH MopIFY THE USEFULNESS OF FER-
TILIZERS— Derivation of soil a guide as to its possible
deficiencies— Physical imperfections of sandy soils— Physi-
cal imperfections of clay soils—The influence of previous
treatment and cropping—The influence of character of
crop—The kind of farming, whether “extensive” or
SETI ESTUS LNG hota cia oe nia 6 ate Goin ie tetele Re icra oS) Oe ine TEC ee 167-177
PLANTS VARY IN THEIR POWER OF ACQUIRING Foop—Char-
acteristics of the cereal group—Characteristics of grasses
and clovers—Root crops—Market-garden crops—Fruit
BEOUE shite noth ws eGo peaeae sk ba kes.ce Pee eames ese Rese ees 177-182
SYSTEMS OF FERTILIZING SUGGESTED—A system based upon
the specific influence of a single element—A system based
upon the necessity of an abundant supply of the min-
erals—A system based onthe needs of the plants for the
different elements as shown by chemical analysis—A
system in which the fertilizer is applied to the “money
crop” in the rotation—An irrational system................ 182-190
EMRE ccc cmic cues: De uei a mana ame eicine wae aunacieu tom aucune 190
CHAPTER X
FERTILIZERS FOR CEREALS AND GRASSES ................ 191-213
EXPERIMENTS TO DETERMINE THE LACKING ELEMENT—A
scheme for plot experiments— Results that may be attained. 193-198
Xll CONTENTS
PAGES
THE IMPORTANCE OF SYSTEM IN THE USE OF FERTILIZERS—
Indian corn exhaustive of the fertility elements—Oats—
Wheat—Clover—Timothy—A gain of fertility by the sys-
tem—The necessity of adding more plant-food than is
required by a definite increase in crop—The system should
be modified if no farm manures are used.............eee0s 198-207
FERTILIZERS FOR A SINGLE CROP GROWN CONTINUOUSLY... 208-211
EERTIDIZERS FOR, LERADOWS< «ses 1s ook «0.5.01 corn clasts etatnets iste were 211
Winn Tas SYsStem or FERTILIZING PAY? <i. c.00cees.cctw en 212, 213
CHAPTER XI
POTATOES, SWEET POTATOES, TOMATOES AND SUGAR BEETS. 214-240
FERTILIZERS FOR POTATOES, EARLY Crop—The time and
method of application—The amount to be applied— Form of
GHG COMSILMMB UES. soe aicia vac set ui 6's atten wate a aretelp ate mor mien aera 215-220
PHP OVAIOGES iad ec oa were sacsse eraeacae ie icles siebalahaietal lee 220, 221
SwEEtT PotatTors—Fertilizer constituents contained in an
average crop—The application of fertilizers ............... 221, 226
ToMATOES— Field experiments with fertilizers for tomatoes—
Fertilizers for the early crop for different conditions of
soil—The use of fertilizers with yard manures— Fertilizers
for late TOMtAhOOS. 6c. cw ecwaxga cd aets das ss se aceateeaMannme 226-235
SuGAR BrEets—The demands of the crop for plant-food—The
influence of previous deep cultivation of soil-............. 235-240
CHAPTER XII
Cerin PORAGH CROPS: J occ. cs cies pean e ee ee 241-261
Maize (corn) forage—Silage corn—Wheat and rye forage—
Spring rye—Oats— Oats and peas— Barley and peas — Millet.
CLOVERS AND OTHER LEGUMES—Cow pea and soy bean—
Alfalfa, or Lucerne—Need of lime for legumes~ Scheme of
BOUIN CROPS il seis eae 5 nis win ee ks o0'< ie ine Dae sis ae ee 249-257
Root Crops—Fertilizers for fodder beets, sugar beets and
carrots—Turnips, Swedes and rape.......ceeseescccccccees 257-261
TUBER: (CROPS dais eveisnintcie gd unsiote sratesaictne ae mise Geek anaes 261
CONTENTS X11
CHAPTER XIII
PAGES
Miaeeme-GAGDEN CROPS ©. ..65 canescens cceceewses see. 262-281
THE YIELD AND QUALITY DEPENDENT UPON CONTINUOUS
a APID GROWPEH. .. lessen ccpcinsctied bocce ve tw cisieinns shone 262-264
ASPARAGUS—The use of salt—Fertilizers that have proved
useful—A basic fertilizer for market-garden crops ....... 264-269
MMSE NC eG Gas Van cloac are Caew'steeine een emis pul w wSame ama 269, 270
Pee eee OENUPE : GS dirn.cicvcls civics games «mae Caden cee anew ein ans 270-272 ©
CABBAGE, CAULIFLOWER AND BRUSSELS SPROUTS .........- 272, 273
CUCUMBERS, WATERMELONS, MUSKMELONS, PUMPKINS AND
RUTTER org sa chs, anes 2 ee se aah sk ae ee were mie’ ew Mie plle oie alee 273-275
ENON M oo. c nnn a dase Bie Wiel ae wiSIp Er E MRE MRI OE SSSR Mw eile iss 275
PemRee OME BEI 4) aise au site lea ace ia ace mn pin ee bw aw aR BiieMiale 276
EGG-PLANT, SPINACH, LETTUCE AND RHUBARB ...........-. 277-278
Ontons, ONION SETS AND SCALLIONS. i. ...020 <5 coe ccen vince 278-281
CHAPTER XIV
ieee PEUIte AND: BERRIES 23. ois se eee bees cin ten 282-304
FRuIT Crops DIFFER FROM GENERAL FARM CROPS......... 283
THE SPECIFIC FUNCTIONS OF THE ESSENTIAL FERTILIZING
ERP RIOT SY ooo 35. « svn ote's iain aersnmary Sain wed has wan Sele me am 284
THE CHARACTER OF SOIL AN IMPORTANT CONSIDERATION... 285-287
THE GENERAL CHARACTER OF THE FERTILIZATION.......0¢. 287, 288
THE APPLICATION OF FERTILIZERS FOR F'RUITS.........-00. 289
THE FERTILIZATION OF APPLES AND PEARS—The amounts
PemaNO A RELOU vo trates <p ies acelin jo bone wea ale Use xa els A awe oe 289-294
PEACHES— The need of fertilizers— Methods of fertilization.. 294-299
PLUMS, CarEntes AND APRICOTS 2.58.0 ..5..6 ccecccandclcockus 299
(LETTER SIS 109 Son a Rg eg ee 299
ents GEES: Tie, GEN BRAT MK + oa siassis weiss, annals nas es tule nd chai 300
UMMMTEIMRES Ec Lect carts Send seit, eth oe eu ea eukiots wake 301
BABPEMNERING. AND BIAGKBEREIUS. .. <0 acsses vicvos accaeacece 302
X1V CONTENTS
PAGES
CUREANTS AND GOOSEBERRIES’ fico science esc soe wis, alsate Se eaiee 303
GRAPES ..... Satie a Pale win ocete eae awe, Shane een at ie teva eo caMiaee ar tie meal 303, 304
CHAPTER “+ V.
FERTILIZERS FOR VARIOUS SPECIAL CROPS......cee-cee- 305-327
Cotrron—Fertilizers for cotton—Formulas for cotton ferti-
izors—eiiOd-DL APPHEATION \ oiciesis)ae ciniee an pawn eels « ee 305-312
Tospacco—The influence of fertilizers upon the quality of
the crop—The conclusions from Conneeticut experi-
ments—Form of the constituents—Amounts to apply ..... 312-317
SuGAR-CANE—The needs of the plant as indicated by the
Louisiana experiments—The application of fertilizers®.... 317-321
MISCELLANEOUS CROPS— Sorghum — Buckwheat — Peanut—
Roses and other flowering plants—Lawn grasses—
Forcing-house Crops»... 5-6. c snes seeded cewnty essen s wee dims 321-327
= # AAAS
: a Sicel per
FERTILIZERS
CHAPTER I
NATURAL FERTILITY OF THE SOIL, AND SOURCES
OF LOSS OF THE ELEMENTS OF FERTILITY
THERE is no one question of greater importance to
the farming industry than that of soil fertility. In
order that the industry may be successful, it is not
enough to produce crops; it is necessary that their
production shall result in a genuine profit. That is, it
is not enough to produce crops which bring more than
they cost in the way of labor and manures, without
taking into consideration the effect of their growth
upon the future productive capacity of the soil. The
relation of the outgo and income of the fertility ele-
ments is an important factor in determining profits,
and must be considered. The farmer who secures
crops that bring more than they cost, and who, at the
same time, maintains or even increases the productive
capacity of his soil, is, other things being equal, the
broadly successful farmer. Many farmers are able to
accomplish this object because of the knowledge they
have acquired through long years of experience, rather
than because they possessed in the beginning of their
work a definite knowledge of the fundamental princi-
A (1)
ae FERTILIZERS
ples involved in crop production, and upon the ob-
servanee of which their success depended. One of
the first needs, therefore, in the use of commercial
fertilizers is a more or less definite knowledge of what
constitutes fertility, and of the principles which under-
lie crop production.
SOIL FERTILITY
The full meaning of the term “soil fertility” is not
easily expressed, since many conditions are involved,
all of which exercise more or less influence. The po-
tential fertility, which is measured by the total content
of the food elements contained in a soil, is made
practicable, or usable, in proportion as the conditions
are favorable. The more important of these infiuenc-
ing conditions are here briefly discussed. In the first
place, it is of the utmost importance that a soil should
contain those elements found in the plant; hence, it is
almost self-evident that a fertile soil must contain a
maximum quantity of those particular elements or
constituents which are removed from the land in
maximum amounts by the crops grown. The removal
of crops rapidly exhausts the soil of these elements,
and finally reduces the quantity contained in the soil to
so low a point as to make profitable cropping impossible.
Chemical Elements Needed in Plant Growth
Careful studies and experiments have shown that
plants actually take from the soil at least ten chem-
ical elements which are required for their normal
THE CHEMICAL ELEMENTS NEEDED 3
growth and development: viz., nitrogen, potassium,
phosphorus, magnesium, sulfur, sodium, iron, chlorin,
silicon and calcium. Yet the number lable to rapid
exhaustion is limited in many eases to three, and at
most to four, which are, nitrogen, phosphoric acid
(phosphorus), potash (potassium), and lime (calcium),
the latter only in exceptional cases. These are liable
to be exhausted because they exist in larger amounts
than the others in the plants that are grown, and in
smaller amounts than the others in even the most fer-
tile soils. It has also been proved that it is the one
element of these which exists in the smallest amount
which measures the crop-producing power, or fertility,
in this respect, as one element cannot substitute or
exert the full functions of another. That is, there
- may be a relative abundance in the soil of potash and
of phosphoric acid, but practically no nitrogen, in
which case good crops of cereals, for instance, could
not be grown, because no other element can substitute
the nitrogen required by the plant, and it can be
obtained by it from no other source than the soil; and
the soil, for all practical purposes, is quite as unpro-
ductive, lacking in productive fertility, as it would be
if it contained much smaller amounts of the mineral
elements mentioned, and thus be poorer in potential
fertility.
Fertility as Influenced by Water, Climate and
Season
In the second place, there are soils that are so rich
in all of these elements that if productiveness depended
4 FERTILIZERS
upon them alone, maximum crops might be grown for
centuries without exhausting them, while actually they
are now incapable of producing a single profitable crop
of cereals, grasses, fruits, or other products of the farm,
because certain other conditions which are essential, in
order to bring them into activity, are absent. For
example, it may be that water, which is absolutely
essential both for the solution of these food elements
in the soil, as well as for their distribution in the plant
after they have been acquired, cannot be obtained, or
that the temperature of the soil and of the surrounding
air is either too low or too high, thus preventing or
interrupting the progress of those changes which must
go on, both in the soil and in the plant, in order that
normal growth and development may be accomplished.
With a full supply of the fertility elements in the soil,
the climatic and seasonal conditions exert an important
influence upon its productive power.
It is evident, therefore, that the chemical elements
of fertility in themselves are not sufficient to constitute
what we understand by the term.. Fertility is not
measured by them alone; associated with them there
must be other: conditions. That is, while crops cannot
be grown without these elements, it is the conditions
which surround them that, in a large degree, deter-
mine the power of the crop to secure them.
The Influence of Physical Character of Soil
In the third place, the physical character of a soil
is also a factor in determining actual fertility. This
LOCATION QUALIFIES FERTILITY 4)
has reference, first, to the original character of the
rocks from which the soil particles were derived,
whether hard and dense in their mineral character, thus
resisting the penetration and the solvent effect of air
and water and other agencies, or whether soft and
friable, and freely permitting their entrance and ac-
tion; and secondly, whether, in the formation of the
soil, the particles were so fine and so free from vege-
table matter as to settle in hard and compact masses,
impervious to water, air and warmth; or whether they
were coarse, and not capable of close compaction, thus
giving rise to an open and friable soil, freely admit-
ting the active natural agencies, such as we find to be
the case in sandy soils. In addition to these properties
of soils, which have a distinct place in determining
fertility, there are many other minor ones which to-
gether constitute what is understood as “condition.”
Location of Soil Qualifies the Term “ Fertility”
Furthermore, fertility, even in this true sense, may
be useless because of the location of the soil which
possesses it. For example, there are many places on
this continent where sugar-producing plants will grow
and develop perfectly, since the soils are very rich
in the fertility elements, and since the surrounding
eonditions are most favorable for their culture, yet,
because of their location, it is unprofitable to grow
them for the manufacture of sugar. In the first
place, the soils are so situated as to make it impos-
sible, or at least impracticable, to provide the means
6 FERTILIZERS
necessary for converting the sugar-producing crop
into actual sugar, and, in the second place, even it
it were possible to do so, the great distance from
shipping stations to markets so increases the cost of
transportation as to make it unprofitable to compete
in the market with the crops grown upon lands pie:
sessing true fertility in a lower degree.
Practical Fertility is Usable Potential Fertility
Practical fertility is, therefore, dependent upon
many conditions, and fortunately our own country
possesses it in a marked degree; that is, the utility
of the potential fertility, as represented by the total
mineral content of our soil, is such as to make us
one of the greatest agricultural nations in the world,
both in the quantity and variety of products grown.
Our soils possess the essential elements in lavish
amounts, and our e¢limatic and seasonal conditions
are such as to permit of their ready conversion into
a wide series of valuable products, and our location
and facilities for handling and distributing our staple
erops are such as to enable us to compete in any
market of similar commodities.
Notwithstanding the truth of this general state-
ment, it is also true that in certain sections of our
country profitable crops cannot be grown without the
addition of commercial fertilizers, because the soils
are either naturally poor, or they have become par-
tially exhausted of their plant-food elements. That
is, the amounts that become available to the plant
WHAT BECOMES OF FERTILITY ¥
through the growing season are not sufficient to
enable the plant to reach a maximum development,
though other conditions are perfect.
Our future progress depends, therefore, upon how
well we understand and apply the principles which
are involved, both in the conservation and use of the
fertility stored up in our soils, and in the use of
purchased fertility; and in this connection it is im-
portant to consider the sources of loss of the essential
fertility elements, or those which in the beginning
measured our capabilities in crop production.
WHAT BECOMES OF OUR FERTILITY ?
Since fertility is dependent upon so many con-
ditions, or, in other words, since the essential elements
of fertility are dependent upon their utility, and since,
in this sense, fertility is largely determined by natural
conditions, it is pertinent to inquire, first, whether
under our present systems of management, or mis-
management, of the land, it is suffering any natural
loss of fertility. As already pointed out, the most
important function of fertility is to furnish nitrogen,
phosphoric acid and potash, and since the content of
these in our soil, together with the knowledge we
have as to their use, measures, in a sense, our pros-
perity as an agricultural people, the possibilities of
losing them from the soil is a matter of national con-
cern, and is of vital interest to individual farmers,
who, in the aggregate, make up that part of the
nation directly affected by the results of such loss.
8 FERTILIZERS
It would, perhaps, be possible, by a careful chemical
survey of our soils, to determine both the actual and
potential fertility of our entire country, and this
knowledge, together with an accurate measure of the
intelligence exercised in its use, would enable a predic- ~
tion as to our future development, if present methods
were continued. That is, whether our land would
become barren and worthless, as has been the case
in many older countries which at one time were quite
as productive, or whether it would constantly increase
in productiveness, even with continuous and profitable
eropping,—though, as already pointed out, the present
barrenness or sterility of a country formerly fertile
may not be due entirely either to the natural or to
the artificial loss of these constituents.
SOURCES OF NATURAL LOSS OF NITROGEN
Of the essential constituent elements, nitrogen is,
in one sense, of the greatest importance; first, because
it is the one that is more liable to escape than the
others, and secondly, because it is more expensive to
supply artificially than are the minerals. It is the
most elusive of all the elements: to-day it may be
applied to the soil, to-morrow it may be carried in
streams to the ocean. It is also unstable—which is
not the least valuable of its characteristics if properly
understood; —to-day it is an element of the atmos-
phere, to-morrow it is a constituent part of a grow-
ing plant, the next day the same element may exist as
an animal product, and the day following it may be
NATURAL LOSS OF NITROGEN 9
returned to the soil to feed the plant. It is more
liable to escape than any of the others, because
it is available as plant-food largely in proportion
as it changes to a nitrate, and after it assumes
that form it is seldom absorbed or fixed in the
soil. Nitrogen in this form remains freely mov-
able, and the probability of loss by leaching is
increased in direct proportion to the lack of preven-
tive measures used, or the presence of those conditions
which favor leaching. The latter may be classified as
follows: First, the amount and time of the rainfall;
secondly, the absorptive and retentive power of the
soil and subsoil, due to their mineral and physical
character; and thirdly, the amount of vegetable matter
(humus) acquired by the soil, which retards the
passage of water. While the amount and time of
rainfall cannot be controlled, its effect upon our soils
in this direction can be largely governed if proper
attention is given to correcting the other conditions,
and these may be largely modified, if not entirely
controlled. In the matter of the absorptive and reten-
tive power of soils, it has been shown that if they are
well supplied with vegetable matter and carefully
cultivated, they retain and hold the plant-food con-
stituents in a much greater degree than if devoid of
humus and improperly managed, and also that the
drainage water from soils upon which crops are grow-
ing seldom contains more than the merest trace of
nitrates. The loss of nitrogen through the opera-
tion of the forces of nature may, therefore, be
reduced by the careful management of the soil.
10 FERTILIZERS
Importance of Careful Culture
The presence of suitable amounts of vegetable
matter, and good cultivation, are conditions that are
within the power of all farmers to provide, though it
is sometimes impracticable to keep the land contin-
uously covered with a crop; and sometimes it is
thought that the loss incurred through leaching be-
cause of the absence of a growing crop is more than
balanced by the gain in other directions. For example,
though losses of nitrates may occur, the gain in
availability’ of the mineral constituents, phosphoric
acid and potash, with the accompanying improvement
in texture, due to the exposure of the soil to atmos-
pheric influence, more than balances these losses, par-
ticularly during the winter, with its wide changes of
temperature. ;
Loss of Nitrogen by Drainage
It has been shown by carefully conducted experi-
ments, both in this and other countries, that in a
season of average rainfall the drainage waters carry
away from one acre, from uncropped soils only fairly
rich in plant food, as much as 37 pounds of nitrogen
per year, while when continually cropped the drainage
waters from the same soils contain practically no
nitrogen. This difference in the loss of nitrogen
under the two conditions may not seem a great matter
at the first glance, but a careful study of the bearing
of this loss in its relation to crop production shows
LOSS OF NITROGEN BY DRAINAGE tt
that it is really a serious matter. In the first place,
the amount of possible loss annually is practically
equivalent in nitrogen to the amount contained in two
tons of timothy hay, or in one ton of either wheat,
rye, oats, corn or buckwheat, quantities nearly double
the average yield per acre of these crops throughout
our whole country; and in the second place, that the
nitrogen which is carried away by the drainage water
is in the very best form for feeding the plant, or it
would not have been lost, and thus its loss leaves the
soil not only poorer in this constituent element, but
poorer in the sense that the remainder of it in the
soil is in a less useful form.
Escape of Nitrogen into the Atmosphere
Another source of natural loss of nitrogen is its
escape from the soil as gas into the atmosphere. This
is due to the oxidation of the vegetable matter, or to
“denitrification,” which takes place very rapidly when
soils rich in vegetable matter are improperly managed.
The possibilities of loss in this direction are strongly
shown by investigations carried out at the Minnesota
Experiment Station on “the loss of nitrogen by con-
tinuous wheat raising.”* The results of these studies
show that the total natural loss of nitrogen annually
was far greater than the loss due to the cropping. In
other words, by the system of continuous cropping,
which is universally observed in the great wheat
*University of Minnesota Agricultural Experiment Station, Bulletin 53.
f
12 FERTILIZERS
fields in the Northwest, there were but 24.5 pounds
of nitrogen removed in the crop harvested, while the
total loss per acre was 171 pounds, or an excess of
146 pounds, a large part of which loss was certainly
due to the rapid using up of the vegetable matter by ©
this improvident method of practice. Whereas, on
the other hand, when wheat was grown in a rotation
with clover, the gain in soil nitrogen far exceeded
that lost or carried away by the crop. The continuous
wheat- and corn-growing in the West, and of cotton
and tobacco in the southern states, are responsible
for untold losses in this expensive element of fertility,
while in nearly every state of the Union, soils both
rich and poor are suffering more or less from the
effect of natural losses in this direction
THE NATURAL LOSS OF THE MINERAL ELEMENTS
In the case of the minerals, phosphorie acid and
potash, which exist in fixed compounds in the soil, the
actual losses are undoubtedly very much less than is the
case with nitrogen, since only traces of these constitu-
ents are ever found in solution in the drainage waters
under ordinary circumstances; yet, because of the large
quantity of water that passes through many of our
soils, the total amount of these rendered soluble and
carried away by this means is very great. Our great
rivers carry in solution into the ocean tons upon tons
annually of these elements of fertility, and it is an
absolute loss, as there is no natural means by which
these may be returned to the soil, as is the case with
MECHANICAL LOSSES OF FERTILITY 13
nitrogen; and it is true, as in the case of the former,
that the soil is not only absolutely poorer by. virtue
of the loss of its elements of fertility, but poorer
in the sense that the immediate utility of those re-
maining is reduced. These silent and unseen forces
constantly at work are reducing the content of these -
constituents in our soils to an alarming degree, and
it is because they are unrecognized forces that the
disastrous results of their activity are not fully appre-
ciated, and, consequently, the best means for restor-
ing them are not used.
Losses Due to Mechanical Means
_ A serious loss of all of the fertility elements is
also due to mechanical means. Aside from the amounts
that the rivers of water are carrying in solution into
the seas, immense amounts are carried in them in
suspension. The results of this kind of loss are pain-
fully evident ; in many of the southern states, and in
sections where the forests have been removed and the
land abandoned, the soils have been washed and
gullied until not only the very best portions, but in
some cases the largest portions, have been carried
away.
It is not, however, in the abandoned parts of
the country alone that these mechanical losses of con-
stituents are of importance—they are more or less
apparent on every farm, and are measured by the
methods of management. Soils that are allowed to
lie bare and fully exposed to the storms of wind and
14 FERTILIZERS
rain througnout the larger portion of the year suffer
the greatest loss, while from those which, on the
other hand, have crops growing during a large part
of the year, and which hold the soil particles together —
and prevent their easy movement, the losses are re-
duced in both the directions mentioned. The benefi-
cial results derived from the use of good methods
are cumulative; the benefit is not only immediate,
but continuous.
ARTIFICIAL LOSSES OF FERTILITY
In addition to these natural losses of fertility, there
are the artificial losses of the constituents, or those
due to the removal of crops. These, of course, neces-
sarily accompany all farming operations, and, provided
that in the removal and sale of the constituents in
the form of crops, the farmer has received a fair
price for them, they are entirely legitimate.
The sale of farm products is really in the last
analysis a sale of actual constituents, together with
a certain portion of the “condition” of our land,
which is not readily measurable. That is, it is the
constituents in the soil, together with the conditions
surrounding it, that the farmer buys when he buys
land. If an acre of land, containing within the reach
of the roots of the plant, say 8,000 pounds of nitro-
gen, 5,000 pounds of phosphoric acid and 6,000 pounds
of potash, sells for $100, the seller receives the $100,
not for so much dirt, but really for the constituents
contained in it. The purchaser believes that, with the
ARTIFICIAL LOSSES OF FERTILITY 15
conditions surrounding them, he can convert them
into products which he can sell and from which rea-
lize a profit. If in selling these amounts of the con-
stituents in the form of land, a lower price per acre
is received, it is because the natural conditions which
surround them, and which influence their utility, are
less favorable, and a greater proportionate effort and
expense are necessary to secure them in the form of
salable products. The difference in the price of land
is not always due to the content of the constituents,
but often to the conditions surrounding them. In
many cases, the soil may serve simply as a medium in
which plants ean grow, and the content of the fertility
elements is of minor importance. Such would be the
case in the growing of market-garden crops near
large cities, the location near the consumer being of
greater importance, in the ease of perishable crops of
this sort, than the chemical character of the soil. In
the large majority of cases, however, the natural fer-
tility fairly measures the market price. At the price
per acre, and for the quantity of constituents here
assumed, the buyer would pay at the rate of 1% cents
per pound for the nitrogen, and % cent per pound
each for the phosphoric acid and potash, and it now
constitutes his capital stock.
A Comparison of the Prices Received for the Fertility
EHlements in Different Crops
A comparison of the prices paid for the constitu-
ents in land, with the prices received for the same
16 FERTILIZERS
constituents when contained in the different crops
(disregarding for the moment the value of the “con-
dition” of soil), will ntake clearer this matter of
rational sale of constituents, which represents a re- _
duction of our capital stock of fertility. For exam-
ple, if wheat is raised, which contains 1.89 per cent
of nitrogen, .93 per cent of phosphoric acid and .64
per cent of potash—or in round numbers, 38 pounds
of nitrogen, 19 of phosphoric acid and 13 of potash
per ton—and is sold for 60 cents per bushel, or $20
per ton, the nitrogen sells in this form for 41 cents
per pound, and the phosphoric acid and potash for
14 cents each per pound. That is, the 60 cents per
bushel, or the 41 cents per pound, received for the
nitrogen, and 14 cents for the potash and phosphoric
acid, represent what has been received per pound for
the capital stock of these elements, which at $100
per acre were purchased at the prices previously men-
tioned. The labor in raising the crop, the expense of
harvesting and putting it upon the market, and the
profit, must come out of the difference between what
is paid and what is received. Naturally, as the ratio
between the constituents contained in the products
sold and the price received is increased, the rate of
income per unit of exhaustion is increased, though
in many cases the increased cost of the labor neces-
sary is in proportion to the increased price received.
This may be illustrated by a comparison on the fer-
tility basis of the sale of wheat and milk. If milk,
which contains on the average 12 pounds of nitrogen,
44% pounds of phosphoric acid and 3% pounds of
FERTILITY CONTENT OF FARM CROPS 17
potash per ton, is sold for $1.50 per hundred pounds,
the nitrogen is sold for $2 per pound, and the phos-
phorie acid and potash for, approximately, 70 cents
per pound. In the sale of milk at this price, the rate
of income per unit of exhaustion is increased nearly
five times over that of the wheat, though, because it
is in one sense a manufactured product, the cost of
labor per unit of plant-food contained is largely in-
creased. Again, if cream is sold, the prices received
for the constituents are still further increased, while
if the milk is made into butter, and that alone is
sold, the prices received measure the expenses and
profit, and the capital stock of fertility is not mate-
rially reduced, though it is in another form and in
another place.
Fertility Content of Cereals and Vegetables
The losses of the constituents in the sale of ce-
reals and grasses, corn, oats, wheat and hay, are, too,
relatively greater than in the sale of vegetables and
fruits, as lettuce, celery, potatoes, tomatoes, sugar
beets, apples, berries and kindred crops, though in
the case of the latter, a higher degree of fertility is
necessary in order to produce maximum crops, and
the cost of production is again proportionately greater.
These facts strongly emphasize the necessity of a care-
ful study of the relation of farm practice to the arti-
ficial losses of fertility.
The artificial loss of fertility that may be incurred
by the sale of crops is largely measured by the knowl-
B
18 FERTILIZERS
edge of the producer concerning the relation between
the price received for the crop and the fertility con-
tained in it, and thus removed when sold, and by his
intelligence in adjusting his methods so as to reduce
to a minimum the actual loss.
Irrational Farm Practice
There are methods of practice which are entirely
irrational, and contribute to the real losses of fertility.
Farming is unprofitable, not altogether because the
land is exhausted, but because only those crops are
grown which possess a high fertility value, and which
have a low market price, and thus the prices received.
for the constituents in the crop are actually less than
they cost in land and in labor; and these methods of
practice are not confined to farmers whose lands of
inexhaustible fertility have been given them by a
generous government, but are followed by farmers
who annually purchase commercial fertilizers to supply
the losses of fertility thus sustained.
Where the conditions are such as to make it im-
practicable to grow and sell crops, as such, of a low
fertility value, the producer should endeavor to sell
the manufactured rather than raw materials,— that
is, to so use his erude products as to lower the quan-
tity of the constituents contained in those sold, which
explains, in part, the greater success in the long run
of a mixed husbandry, rather than single-crop
farming.
The artificial losses of our national capital stock of
IRRATIONAL FARM PRACTICE 19
fertility are, however, not absolute, if the products
are consumed in our own country, as more or less of
the constituents contained in the crude ,products sold
find their way back to the farm, either in the by-
products of the mills, in sewage, in the manure from
cities, or in various vegetable or animal wastes; but
when they are exported the loss is absolute, and the
amounts so disposed of are in some degree a measure
of the rate of loss of the capital stock of fertility in
our lands, though to these must be added the losses
due to the improper use of manure and other waste
materials.
Losses in Manures
It is natural to infer that proper losses of fertility
are confined to the removal of the constituents in the
sale of farm products, and that those contained in the
materials not sold and in the feeds used upon the farm,
are again returned to the land. Theoretically this is
correct, but the losses that do occur, particularly in
the handling of manures, should not be overlooked.
While it is impossible to even roughly estimate the
waste or loss of fertility due to the improper making
or handling of manures, some idea may be obtained
when the enormous amounts produced and the sources
of possible loss are considered.
If this enormous mass of waste material were
properly used, it would go a great way toward increas-
ing the present and immediate fertility of our soils, or
in retarding the time of exhaustion, and it is quite
pertinent to inquire if it is properly used. It has
9() FERTILIZERS
been demonstrated by experiments* that 50 per cent
of the total constituents in farm manures is liable to
be lost by ill-regulated fermentation and by leaching ;
and further, careful observations and experiments
show that the conditions in the majority of barnyards
are such as to encourage the maximum loss by these
means. It is morally certain that a large percentage
of the constituents contained in them are lost; they
never reach the right place on the farm.
It is estimated that if but one-tenth of the present
waste could be avoided,— and a very large part of it is
practically avoidable, and at a very slight expense,—
the total amount of constituents that may thus be
saved for further use would be more than equivalent
to the amounts now purchased in the form of com-
mercial fertilizers. This estimate is certainly conser-
vative, and clearly demonstrates the serious drain
upon our resources of fertility elements, due to the
lack of care in the handling of farm manures.
The conditions, as here pointed out, not only sug-
gest the need of imported plant-food, but that there
are opportunities for reducing this need by careful
saving and use of the constituents that are subject to
waste.
*Bulletin 56, Cornell Univ. Agr. Ex. Sta., Ithaca, N. Y.
CHAPTER II
THE FUNCTION OF MANURES AND FERTILIZERS, AND
THE NEED OF ARTIFICIAL FERTILIZERS
WHILE in a broad sense, a manure or fertilizer may |
be regarded as anything that will increase the yield of
a crop if added to the land, the chief function of
manures is to furnish nitrogen, phosphoric acid and
potash.
THE ESSENTIAL ELEMENTS OF FERTILIZERS
These are called the “essential manurial elements,”
or “constituents,” to distinguish them from the others
that are needed by plants, because these three are con-
tained in the crops removed in greater amounts than
the others, and because they exist in the soil in much
smaller amounts than the others. For example, eculti-
vable soils seldom contain too little iron or sulfur, or
magnesium. These elements usually exist in quantities
more than sufficient to supply all the needs of the
plant for them, and, because they are required in such
exceedingly small amounts, the soils are seldom ex-
hausted of them. In addition to this property of
supplying essential manurial constituents, many sub-
stances useful as manures possess, however, a secondary
function: they serve to indirectly increase the crop,
(21)
S)S) FERTILIZERS
—
but do not add directly to the potential fertility of
soils.
NATURAL MANURES AND ARTIFICIAL FERTILIZERS
Farmyard manure, and many other natural pro-
ducts, possess this second function in a marked de-
gree, and the indirect manurial value of these is due
largely to the good effect that the substances asso-
ciated with the nitrogen, phosphoric acid and potash
in them exert in inereasing the crop. This good
effect is observed in two directions. First, the vege-
table matter contained in the natural manure improves
the physical character of soils—those that are clayey
and compact, by making them more open and porous,
separating the particles, so that the water and air can
penetrate more freely, and thus act directly upon the
dormant or insoluble constituents that are contained
in it; and those that are light and sandy, by filling
up the open spaces, thus making them more compact.
In the second place, the addition of vegetable matter
to soils, even though it contains no essential consti-
tuents, improves it by enabling it to more readily and
completely absorb and retain not only the water, but
also the soluble essential constituents that may be
added. The chief distinction between what are
known as manures and what are known as ferti-
lizers, is the difference in respect to this secondary
function. The manure possesses the two functions,
the one to supply the essential constituents, and the
other to assist plant growth by aiding in the improve-
ment of those already contained in the soil, and this
THE FUNCTIONS OF MANURES 93
latter function it exerts in a marked degree; while the
fertilizer, as a rule, possesses but one, namely, that
of furnishing plant-food. The indirect effect of the
materials associated with the constituents in artificial
fertilizers is seldom very useful, and sometimes may
be harmful.
DIRECT AND INDIRECT EFFECT OF MANURES
It is obvious, therefore, that any substance which
contains nitrogen, phosphoric acid or potash may
serve as a direct manure, and any substance which
contains no plant-food, but which possesses the power
of improving the physical character of soils, may also
serve aS a manure, though the one effect is quite dis-
tinct from the other. The first adds to the soil the
essential constituents; the other helps to make the con-
stituents already in the soil serve as food to the plant.
The use of the one will tend to increase both the
potential and practical fertility in the soil, while by
the use of the other, the active fertility is increased
as the potential fertility is decreased. That is, when
actual plant-food is added in the form of nitrogen,
phosphoric acid or potash, and crops are removed, the
exhaustion of the soil is in proportion to the amounts
of these removed over and above the amounts which
have been added. Whereas, in the other case, when
no plant-food is added, the exhaustion is measured by
the amount of the constituents removed. It is clear,
therefore, that the addition of only indirect manures
has a tendency to rapidly reduce the fertility of soils
94 FERTILIZERS
of low natural strength, or those that do not possess
large stores of food constituents, whereas, on soils
that are rich in the fertility elements, the indirect
manuring may result in an increased yield for a long
period, though ultimately the soil will become ex-
hausted—if not completely, to such a degree as to
render further cropping by this method unprofitable.
UNAVAILABLE AND AVAILABLE PLANT-FOOD
While, as already stated, any material containing
either one or all of the three essential constituents,
nitrogen, phosphoric acid or potash, may serve as a
direct manure in the sense that it increases the poten-
tial fertility of any soil, the value of the addition of
‘such materials will depend not so much on the
amount, as upon the power that the plant may
possess of acquiring it—and it is here that the dif-
ference between manures from natural sources and
those from artificial sources is again quite manifest.
That is, the fertility constituents in natural manures
are in large part combined with others in the form of
vegetable matter, and with the exception of potash,
they are, when in this form, largely insoluble, and,
therefore, cannot be used by the plants until after
decay begins. Whereas, in artificial manures, the
constituents may be not only soluble, but may be in
a form in which the plants can take them up im-
mediately. In the first case, the plant-food is said
to be unavailable, and in the second, it is said to be
available.
AVAILABLE PLANT-FOOD 95
Nitrogen, one of the chief constituents of manures,
for example, exists in three distinct forms: (1) the
organic form, in animal or vegetable matter, which
must first decay before it can serve as plant-food. (2)
As the decay goes on ammonia is formed, and then
(3) from the ammonia the nitrate is formed, which is
the form in which plants take up the largest proportion
of their nitrogen. Inasmuch as products exist which
contain nitrogen in these three distinct forms, it is
possible by their use to largely control the feeding of
the plant in respect to this element, while in the ease
of natural manures, the feeding of the plant with
nitrogen depends upon conditions which cause its
change from the organic into the other forms.
As these conditions are variable, the problem of
the economical feeding of plants with nitrogen, other
things being equal, becomes a more difficult matter
with the natural than with the artificial manures.
Phosphoric acid also exists in different forms, the
form measuring to a large degree its availability: the
organic, in which the availability depends upon the
rapidity of decay; and the soluble and immediately
available form,—that is, the form that distributes
everywhere, and which the plant can absorb immedi-
ately it comes in contact with the roots. Commercial
products exist which contain the phosphoric acid in
these distinct forms. The user is therefore enabled
to supply this constituent in such form as may best
suit his crop and soil conditions.
In the ease of potash, distinct forms, as muriate,
sulfate and carbonate, also exist, though in the case
296 FERTILIZERS
of potash, the form in which it is combined exerts
less influence upon the availability of the element to
the plant than is the case with nitrogen and phos-
phorie acid. All of these forms are soluble, and can
be readily absorbed.
DANGER OF LOSS FROM THE USE OF SOLUBLE
PLANT -FOOD
The fact that the artificial fertilizer-products con-
tain the constituents in such forms and combinations
as to enable them to feed the plant immediately, also
presents some disadvantages from the standpoint of
economical use. This is particularly true in the case
of nitrogen, for nitrogen, when applied in the form
of nitrate, in which form it is taken up by the plant,
does not combine to make insoluble compounds, but
remains freely soluble. A great waste, therefore, may
ensue from leaching into the lower layers of the soil
and beyond the roots of plants, or into the drains,
and the plant-food be carried away, unless care is
exercised both as to the amount and the method of
application. With soluble phosphates, the danger of
loss is much less than with nitrogen. If these are ap-
plied in too large quantities to meet the needs of the
plants, or under improper conditions, their tendency
is not to remain soluble, but to revert to their
original and insoluble form. The main fact, however,
is that in artificial fertilizers we may have the con-
stituents in distinct and separate forms,. which permits
the feeding of the plant, rather than the feeding of
CHEMICAL FERTILIZERS ARE EFFICIENT 27
the soil; and this is usually, and must necessarily
be, the case when natural manure products serve as
the entire source of the added fertility.
THE USEFULNESS OF A FERTILIZER CONSTITUENT DOES
NOT DEPEND UPON ITS ORIGINAL SOURCE
It should be remembered, too, that artificial ma-
nures or fertilizers supply plant-food just as well as
other and more common products. The fact that
the food exists in substances other than those which
are familiar to the farmer, is no evidence that it may
not be quite as good, or even better, than when con-
tained in his home-made products. It is not the out-
ward appearance of a substance, but the kind and
form of the elements contained in it, that measures
its value as a fertilizer.
For example, the nitrogen that may be applied in
the form of a commercial fertilizer exerts no different
funetion in the plant than that which may be acquired
from the original soil, or from materials that have
recently been obtained from that soil, and again
returned as yard manure. The same is true of phos-
phorie acid and potash. In their concentrated, artificial
forms, they serve to feed the plants in exactly the
same way, and exert the same function in them, as
those contained in the soils themselves, or that may be
contained in wood ashes, or materials more familiar,
or of more common occurrence. The form in which
they exist when applied does not necessarily imply
that they are stimulants rather than food, though fre-
I8 FERTILIZERS
quently, because of their form, the plants are able to
absorb them more readily, and thus by their rapidly
increased growth, encourage a belief that an undue
stimulating effect accompanies their use. The famous
experiments of Lawes & Gilbert, at Rothamsted,
England, teach this one thing very emphatically; viz.,
the efficiency of chemical fertilizers as compared with
yard manures.*
USE OF FERTILIZERS
While manures in the ordinary sense, and even
materials which are now included under the head of
artificial manures, such as ground bone and wood
ashes, have been used for a very long time, the use
of artificial products in a true sense is of compara-
tively recent origin. The first use of genuine artificial
fertilizers dates from the publication of Baron von
Liebig’s book, “Organic Chemistry in Its Application
to Agriculture and Physiology,” in 1840; yet for a
long time after this date the increase in their use was
very gradual. The very excellent, and at that time
surprising, results which were obtained from the
application of Peruvian guano, one of the first
products to receive attention, manifestly increased the
interest in the subject, also. These good results were
observed more particularly on the continent of
Europe, where the lands had been under cultivation
for a long time. The use in America, previous to
1860, was quite insignificant. Since the work of
——. —___=
* Rothamsted Memoirs, Volumes i.-vi.
THE USE OF FERTILIZERS 99
Liebig, a very great amount of study has been given
to the subject, both in reference to the essential char-
acter of the various materials, and their influence
upon the production of plants. Perhaps no other
single subject relating to agricultural science has been
studied more fully than the question of the use of
artificial manures; and these studies have resulted,
not only in the discovery of new materials, but in
their better preparation for use as plant-food, which
greatly imereased their effective use. There is no
question connected with agriculture which is of greater
direct and practical importance, particularly in those
countries which have been depleted of their active
fertility by the means mentioned, or in which the
conditions are as previously outlined, than definite
knowledge of the true principles which govern in the
profitable use of commercial fertilizers. Yet, not-
withstanding all the good results thus obtained, and
their great practical importance to agriculture, much
still remains to be done, particularly in the establish-
ment of fundamental principles.
While it is desirable that in a work of this kind,
scientific discussions should be avoided as far as pos-
sible, and the subject made as plain as is practicable
to those using fertilizers, it is necessary to their
right use that those who apply them to their land
should have a very clear conception of the underlying
principles, so far as they are known, in order that
they may intelligently increase their production, and
thus reap a profit. Definite knowledge is an im-
portant factor in determing their profitable use.
30 FERTILIZERS
THE NEED OF ARTIFICIAL FERTILIZERS
The considerations in the previous’ chapter
explained in part, and in a broad, general way, the
necessity for the use of commercial fertilizers. The
conditions of farming in this country have greatly
changed in the past thirty years, and these changes
have, perhaps, a still more important bearing in show-
ing the need of imported fertility than the conditions
already discussed. The first direction in which
important changes have taken place is in the in-
creased cost of farm labor and in the relatively low
prices now received for the staple crops, the cereal
grains, cotton and tobacco.
The Cost of Production per Unit of Income
is Increased
The cost of labor is increased because proportion-
ately higher wages are now paid, and because the
labor now obtainable is on the whole less efficient,
being performed more largely by those untrained
for their work, rather than by the owner and his
sons; and this increased cost of labor makes the cost
of growing the staple crops much greater in propor-
tion to their market value than was formerly the
case, though there are, of course, exceptions.
For example, harvest wages throughout the east-
ern part of the country, at any rate, were in the
sixties regulated somewhat by the price of wheat.
When wheat was $3 per bushel in the eastern states,
THE NEED OF FERTILIZERS 31
the daily wage was $3. Now the daily wage in the
east ranges from $2 to $2.50 per day, while the price
of wheat does not often exceeed $1 per bushel, and
the price received is frequently much lower than
this. The wages for other kinds of farm work are
proportionately the same in reference to _ present
prices of products. This condition, when considered
in connection with the important fact that the total
eost of crop per acre is practically the same, whether
the yield is high or low, exerts a decided influence
in determining profits, particularly on land of
medium fertility. The cost of preparing the land for
the seed, the cost of seed, and the seeding and
harvesting, are the same for a crop of wheat, whether
the yield is 10 or 30 bushels per acre; but this cost
will not permit a profit from the 10-bushel yield,
because the cost per bushel is too largely increased.
The same considerations hold true for a number of
other crops. Small yields of these relatively low-
priced crops eannot be profitably produced with the
present high price of labor; and it has been shown,
furthermore, that land which is not in a high state
of fertility will not produce large yields.
Many soils, especially those in the eastern and
southern sections of our country, which were not
originally very fertile, and which have been cropped
for a long time, show abundant evidence of the need
of fertility from sources outside of the farm, in order
that maximum crops may be produced. The aim should
be, therefore, to make the conditions of soil better, and,
if possible, so perfect as to guarantee against any
a4 FERTILIZERS
lack of food during the growing period, and thus
make the conditions of climate and season, rather than
the soil, the measure of the crop. That is, as far as
practicable, the yield that it is possible to obtain in a
given locality should be the aim of the farmers in that
locality. In order to make the conditions of soil per-
fect in this respect, the fertility elements must. be
added, though indirect manuring, in the form of better
cultivation and better use of the waste products of the
farm, are also to be encouraged.
A Greater Demand for Special Crops
In the second place, the changed conditions of
farming are shown in the constantly increasing demand
for market-garden products and fruits. Not many
years ago, the staple crops already described were prac-
tically the only ones raised and sold from the farm.
The growing of vegetables and fruits was limited. They
were regarded as luxuries, and the area given to them
was, on most farms, only sufficient to meet the needs
of the home. These were not regarded as crops in the
same light as the others, and were seldom the source
of direct income. At the present time, vegetables and
fruits are regarded as necessities in every home, and
their use is not confined to the season in which they
can be provided in the immediate vicinity of the cities
or towns where they are used; they are drawn from
points far distant, and the demand is such as to re-
quire the use of wide areas in order to supply the
needs. The growing of market-garden crops and fruits
FARM MANOURES ARE INADEQUATE 33
is now the basis of specific agricultural industries
which have assumed large proportions.
Much progress has been made, too, in the develop-
ment of methods of practice in these lines of farming,
and the experience gathered has shown that even our
most fertile soils in their natural conditions contain
too little active food to insure maximum yields of crops
of the best quality; in these lines of farming, too,
earliness and edible quality of products, which are
influenced by the food supply, are important factors in
determining the profits to be derived. The areas now
necessarily devoted to these crops are so great that
soils of a high natural fertility, even if natural fertility
alone could be depended upon, are too limited to meet
the demand and enable a profit, especially in the vicin-
ity of good markets; in other respects a good location,
because permitting of cheap distribution, is an impor-
tant factor.
Farm Manures are Inadequate
Farm manures might meet the needs for the staple
crops, as they are well adapted in many respects for
the purpose, but, under present systems of manage-
ment, the amount is not sufficient to meet the annual
losses from the sale of crops, much less to provide an
increase, and the only other source is an artificial
supply, or commercial fertilizers. For the special
crops already described, the natural manures of both -
farm and ecity are not only not sufficient, but, because
of their character and composition, are not well adapted
&
34 FERTILIZERS
to economically meet the entire demands of the plants.
In the first place, they are bulky, and thus expensive
to handle. In the second place, the fertility elements
contained in them are not in good proportion; they
are, as a rule, poor in the mineral elements and rich in
nitrogen, and their use in sufficient amounts to meet
the needs of the plant for the mineral elements results
in a waste of the nitrogen. Third, the constituents
contained in them are not in sufficiently active forms
to provide for a rapid and continuous growth without
an excessive application, which frequently results in a
serious waste not only of the nitrogen, as already indi-
eated, but, in the case of many crops, an abnormal
growth of vine or stalks, which may seriously injure
the marketable quality of the crops. For many crops,
economical production requires that the natural ma-
nures should be supplemented by artificial supphes, by
means of which the form and amount of the individual
constituent can be regulated to meet the needs of the
various plants.
The Growing Importance of Frwit-growing
In fruit-culture, an industry of growing importance,
it has been found that soils in their natural condition,
while they may be well adapted in other respects—that
is, possess a suitable physical character for the growth
of this class of crops—contain insufficient amounts of
the mineral constituents which are required in order
that continuous and large crops of perfect fruit may
be secured. ‘To supply this deficiency from vard ma-
THE RIGHT USE OF FERTILIZERS 35
nure would cause in many cases an over-supply of vege-
table matter containing nitrogen, which for these crops
is frequently followed by disastrous results, not only
causing an abnormal growth of leaf and wood, but
inducing it at such periods of the year as to materially
interfere with the proper ripening of both the wood
and the fruit. By the use of artificial fertilizers, these
difficulties may be largely overcome.
WILL IT PAY TO USE FERTILIZERS ?
It must be confessed that to give a definite and
positive answer to this question, with our present state
of knowledge, is a difficult matter, if not well-nigh
impossible, because of the very large number of vary-
ing conditions that are involved.
Usually such a question cannot be answered in a
rational way without first securing definite information
concerning the conditions under which they are to be
applied, as, for instance, the character of soil, whether
a sand, clay or loam; situation in reference to mois-
ture, whether too dry or too wet; the kind of subsoil,
whether a loose, open sand or gravel, a medium clay,
or a tight, impervious hard-pan; the character of the
previous treatment and cropping, whether the land has
been manured or fertilized, whether good cultivation
has been practiced, whether leguminous crops have
been grown to any extent, whether the produce raised
has been sold, or fed on the land; whether the object
of the growth has been for immature produce and for
early market, and artificial growth demanded, or
36 FERTILIZERS
whether for maturity, when the natural tendency has
simply been assisted and the development normal in
all directions.
If these questions are answered truthfully and in
detail, a scheme of fertilization may be adopted that
will enable the farmer to secure the greatest returns
for the plant-food applied.
That the returns from the use of fertilizers are
frequently unprofitable, is not always the fault of the
fertilizer, and this point may be _ illustrated by
the following typical case: One farmer applies
plant-food, his crop is doubled or trebled, and a rea-
sonable profit is secured. Another farmer applies the
same amount and kind of fertilizer under similar
natural conditions of soil, and he receives no benefit.
The same climatic conditions surrounded the crops of
both, the sun that warmed the soil and furnished the
energy necessary for the production of the largely
increased crop, is the same sun that shone upon the
small erop; the air that furnished a large proportion
of the food for the one is the same air that surrounded
the other; the rains that moistened and assisted in
the solution and circulation of plant-food for the one
were the same for the other. Why, then, the difference
in results? In one ease the natural agencies, sun, air
and water, were assisted and enabled to do their
maximum work, while in the other, they were pre-
vented from exercising their full influence. Physical
conditions of soil were imperfect, due to careless plow-
ing, seeding, cultivation and cropping.
In other words, the profit from the use of plant-
THE WASTEFUL USE OF FERTILIZERS 3 6
food is measured to a large degree by the perfection of
soil conditions, which are entirely within the power
of the farmer to control. The production possible
from a definite amount of plant-food can be secured
only when the conditions are such as to permit its
proper solution, distribution and retention by the soil.
The fact that fertilizers may now be easily secured,
and the ease of application, have encouraged a ecare-
less use, rather than a thoughtful expenditure, of an
equivalent amount of money or energy in the proper
preparation of the soil. Of course, it does not follow
that no returns are secured from plant-food applied
under unfavorable conditions, though full returns
cannot be secured under such circumstances. Good
plant-food is wasted, and the profit possible to be
derived is largely reduced.
Again, because farming, in its strict sense, is the
conversion of three essential elements into salable
products, the time to apply plant-food must be
governed largely by its cost and the kind of crop
upon which it is applied.
CHAPTER III
NITROGENOUS FERTILIZERS
NITROGEN is the most expensive constituent of fer-
tilizers, and, all things considered, it is one of the
most useful. Nitrogen exists in nature as a compo-
nent of the air, and though quite as necessary to
vegetation as carbon or oxygen,—which also exist in
the atmosphere, and which are readily acquired by
all plants,—all plants do not have the power of aecquir-
ing nitrogen from this source. This power seems to
be limited to a class of plants called Leguminose, to
which belong the various clovers, peas, beans, vetches,
and a number of others. The important farm crops
belonging to the other botanical groups of plants
obtain their nitrogen largely, if not altogether, from
the soil. :
Vegetable or animal matter containing nitrogen
may serve as a source of nitrogen to plants, though
it cannot feed them with this element to any extent
until it decays or rots. In order to obtain a clear
conception of the use of nitrogen as a fertilizer, we
should understand the need of plants for it, what is
meant by form of nitrogen, and the sources from
which the various forms may be derived, as well as
the relative agricultural or crop-producing value of
the nitrogen in existing commercial forms.
(38)
FORMS OF NITROGEN 39
WHAT IS MEANT BY FORM OF NITROGEN ?
Strictly speaking, form of nitrogen has reference
to its combination or association with other chemical
elements, though sometimes the term form is used
to indicate rate of solubility, which also measures
to some degree availability, since it happens that
soluble forms of nitrogen are really more available
than the insoluble forms, though neither the soluble
nor insoluble forms show the same rate of availabil-
ity; that is, a pound of soluble nitrogen is not equally
available from whatever source derived, and a pound
of insoluble from one source may be much more avail-
able than a pound from another. The form in which
nitrogen exists in vegetable and animal matter is
ealled the “organic form,” because it is associated
with other constituents, as carbon, hydrogen and
oxygen, which are necessary to make the substances
that constitute animal or vegetable matter, as we see
them. The term “organic,” as applied to nitrogen,
covers a whole series of substances, and does not
indicate a uniformity, either in content or quality of
the nitrogen, as is the case with distinct chemical
compounds; hence, associated with the knowledge of
form of nitrogen, when it exists in organic products,
must be a knowledge of whether the material contains
a very considerable amount of nitrogen, and whether
it is likely to be readily changed, and thus become
available as food for plants.
Any nitrogenous vegetable or animal matter may
serve as a fertilizer, though organic nitrogen in com-
40 FERTILIZERS
mercial fertilizers is usually obtained from products
relatively rich in this constituent, and it is only these
that can be used to advantage in making what are
known as “high-grade fertilizers.” The leading ani-
mal substances of this class are now mentioned.
DRIED BLOOD
One of the chief products from which organic
nitrogen is derived for commercial fertilizers is dried
blood. It is one of the most important, because it is
one of the most concentrated, one of the richest in
nitrogen of the organic nitrogenous fertilizing ma-
terials, and it is one of the best, since its physical
character is such as to permit of its very rapid decay
in the soil during the growing season. This tendency
to rapid decay is plainly apparent, when we remember
that blood as it exists in the animal is in a fiuid
form, and naturally any material which is sufficiently
finely divided to permit of its ready flow, and is not
associated with any hard or fibrous material, possesses
characteristics which enable a rapid breaking down
when subjected to the proper temperature and mois-
ture, conditions which promote decay.
Dried blood for fertilizing purposes is chiefiy ob-
tained from the large slaughtering establishments, and
the markets recognize two distinct kinds; namely, that
which is red and that which is black. The red dried
blood results from the careful drying of the fresh
blood with hot water, at which temperature it does
not char, nor become injured in quality. When dried
HIGH-GRADE NITROGENOUS MATERIALS 41
at a higher temperature, and by other methods, it is
darker in color, and has a leathery character, is less
useful in the arts, and is slower to decay. Red blood,
which commands the highest price, is reasonably uni-
form in composition. It contains from 13 to 14 per
cent of nitrogen, and but traces of phosphoric acid—
it is always classified as “high-grade.” The black dried
blood is of a lower grade, and may range in content
of nitrogen from 6 to 12 per cent; it also contains
considerable phosphoric acid, frequently as high as 4
per cent. Usually the lower the content of nitrogen, the
higher the content of phosphoric acid; the latter is
contained in the impurities (other substances, largely
bone) with which it is contaminated. The lower grade
blood is very generally used in the manufacture of
fertilizers, since it is really the only good use to which
it may be put; the high-grade is useful for other
commercial purposes.
DRIED MEAT OR MEAL, AZOTIN, AMMONITE, OR
ANIMAL MATTER
Dried meat or meal, azotin, ammonite, or animal
matter, are terms applied to practically the same pro-
duct, though produced in a different way. This ma-
terial is another source of high-grade organic nitrogen.
It is rich in the constituent element, and also decays
rapidly in the soil. When relatively pure, it contains
as high as 13 or 14 per cent of nitrogen, and thus in
this respect compares very favorably with blood. The
largest supply comes from rendering establishments,
49 FERTILIZERS
where the different portions of dead animals are util-
ized. These are subjected to treatment, usually dried
and extracted with steam, for the purpose of securing
the fat, though formerly, and even now, a large por-
tion of this product is obtained from the beef extract
factories.
HOOF MEAL.
Hoof meal is a reasonably uniform product, rich
in nitrogen. It averages as high as 12 per cent, and
in reference to availability has heretofore been classed
with leather and horn. In recent culture experiments,
however, the results indicate that it is much more
valuable as a source of nitrogen than horn meal,
leather, wool or hair. Commercially, it ranks with
the high-grade products.
DRIED AND GROUND FISH, OR FISH GUANO
This product is obtained from two sources: first,
from the offal, largely bones and skins, of fish packing
or canning houses; and second, from the fish pomace
resulting from extraction of the oil from the men-
haden. The latter product is richer in nitrogen and
is more uniform in character than the wastes from
the packing houses. Dried ground fish from this
source contains from 7 to 8 per cent of nitrogen, and
from 6 to 8 per cent of phosphoric acid. The former,
owing to the varying proportions of bone, skin and
flesh contained in it, varies widely in its content of
TANKAGE 43
nitrogen. Fish, besides affording a considerable supply
of nitrogen, is also regarded as a good source of this
element, ranking in availability well up to blood and
tankage, and is largely used in the northern coast
states, where the supply is reasonably abundant.
KING CRAB
King ecrab is found in considerable quantities
along the Atlantic coast, and is not only used directly
as a fertilizer, but is also dried and ground and intro-
duced into commercial mixtures. It is a highly nitrog-
enous product, containing in the dry state an average
of 10 per cent, with traces only of phosphoric acid.
It also possesses a high rate of availability, though
information on this point is derived from the practical
experience of farmers, rather than from actual scien-
tifie test.
TANKAGE
Tankage is a highly nitrogenous product, and con-
sists chiefly of the dried animal wastes from the large
abattoirs and slaughtering establishments. It is va-
riable in its composition, since it includes the otherwise
unusable parts of the carcass, as bone, tendons, flesh,
hair, etc. The portions of this from the different
animals not only vary in their composition, but they
are used in varying proportions, which naturally re-
sults in an extremely variable product. What is known
as “concentrated tankage,” which is obtained by evap-
44 FERTILIZERS
orating the fluids which contain certain extractive
animal matter, is the richest in nitrogen, and is more
uniform in character than the others; and because of
its fineness of division and physical character, the
nitrogen contained in it is also more active than in
the other forms. Two distinct kinds of tankage ean,
therefore, be obtained; first, concentrated tankage,
which is the richer in nitrogen, ranging from 10 to 12
per cent, and which contains very little phosphoric
acid; and second, crushed tankage, which is of several
grades, ranging from 4 to 9 per cent nitrogen, and
from 3 to 12 per cent of phosphoric acid. Products
are sometimes sold as tankage, which contain much
more than the maximum of phosphoric acid and less
than the minimum of nitrogen here given, in which
ease they are to be classed with bone, rather than with
tankage. Tankage varies so much, both in its content
of phosphoric acid and nitrogen, that in the trade it is
always sold on the basis of its composition. The per-
centage of nitrogen and phosphoric acid is distinctly
stated, and because it contains very considerable
amounts of phosphoric acid, its commercial value is
not wholly based on its content of nitrogen, as is the ©
ease with dried blood, dried meat, and concentrated
tankage.
GARBAGE TANKAGE
Garbage tankage is a name given to a product now
obtained by the drying, and sometimes partial charring,
of the garbage of cities. It usually contains variable
LEATHER, WOOL AND HAIR 45
percentages of all of the constituents, though chiefly
valuable for the nitrogen, and as yet cannot be classed
among the standard fertilizer supplies, because of its
variability, and because the usefulness of the con-
stituents have not yet been determined.
LOW-GRADE NITROGENOUS PRODUCTS
Other products which contain a high content of
nitrogen are frequently used. These, because of their
low rate of availability, constitute a separate and dis-
tinct class. For example, horn meal, or ground horn,
is reasonably uniform in its composition or content of
nitrogen. It contains as high as 10 or 12 per cent of
nitrogen, but it is so slow to decay when used in its
natural state, that it is not regarded as an economical
source of this element, though it may be obtained at a
very low price.
Leather meal.—Leather meal is another product
which is rich in nitrogen, but which is so slow to decay
that its use in the natural state is not recommended.
One object in making leather is to render it resistant
to the conditions which promote decay, and ground
leather may remain for years in the soil in an un-
changed condition.
Wool and hair waste.—Wool waste and hair waste
are also products which exist in considerable quanti-
ties, and while variable in composition, are frequently
rich in nitrogen, but they are classed with leather
because of their slow activity. Their mechanical form,
coarse and bulky, makes it impossible to use them to
46 FERVILIZERS
advantage in the manufacture of fertilizers without
previous treatment. The use of these materials, un-
treated, can only be regarded as desirable when they
may be obtained at a very low cost. When dissolved
with acid, or treated in such a way as to render them
more immediately available, they may be used to ad-
vantage, though the cost of such treatment is usually
so great as to make it impossible to thus improve their
form and still be able to compete commercially with
the other nitrogenous products.
VEGETABLE NITROGENOUS PRODUCTS
Cotton-seed meal is one of the best of the vegetable
nitrogenous fertilizing materials. It is reasonably con-
centrated, and decays rapidly. Tests which have been
made show that it ranks with blood in the availability
of its nitrogen. Properly prepared, that is, when free
from hulls, this product contains nearly 7 per cent of
nitrogen. It is used in very large quantities, particu-
larly in the southern states, where it is in abundant
supply. It is, however, a most excellent cattle feed,
and its use directly as a fertilizer will be reduced in
proportion as its usefulness for this purpose is more
fully appreciated.
Tinseed meal is a material somewhat similar in
character to cotton-seed meal. It contains on the
average 5.5 per cent of nitrogen. The demand for
this product for feeding purposes at good prices makes
it, however, an expensive source of nitrogen.
Castor pomace.—Castor pomace, the waste resulting
NATURAL GUANOS 47
from the extraction of oil from the castor bean, is also
a valuable nitrogenous fertilizer. It contains, on the
average, 6 per cent of this element, and decays
rapidly in the soil. This product differs from the
ecotton-seed and linseed meal, in that it is not useful
as a eattle food. Practically its only use is as a
fertilizer.
NATURAL GUANOS
A series of nitrogenous products which constitute
still another separate class, consists of the various
natural guanos. These were formerly a very large and
valuable source of nitrogen, though at the present
time they are not commercially important, owing to
the practical exhaustion of the best supplies. Of the
guanos, the product obtained from Peru, or from
islands on the coast of that country, is the richest in
nitrogen. It is derived almost entirely from the ex-
crement of sea birds, as well as from the remains of
the birds themselves, and from various other animals.
The composition of this guano is of a very complex
character. The nitrogen exists largely as ammonia,
combined with oxalates, urates, humates, sulfates,
phosphates, carbonates, and to some extent in purely
organic forms. In these forms the nitrogen is quickly
available, and marvellous results are obtained from
their use.
Other guano deposits of considerable value, though
poorer than the Peruvian, are found farther north on
the coast of South America, as well as upon certain
48 FERTILIZERS
islands on the southwest coast of Africa. Ichaboe
guano, for example, is at present exported, though it
is a fresh deposit, and is annually collected for ship-
ment. It is very inferior to the Peruvian guano,
containing a very considerable amount of insoluble
matter. At the present time, too, we have “bat guano,”
found in caves in Mexico and in some of the south-
western states. This product is very inferior to the
Peruvian guano in its content of nitrogen, though the
form is good, a considerable portion existing as nitrate.
Owing to the very excellent results that were obtained
from the early use of guanos, many attempts have
been made to improve the lower grades obtainable at
the present time, by the addition of nitrogenous matter
of a higher rate of availability. These rectified, or
fortified guanos, while containing nitrogen in good
forms, cannot entirely substitute the original guanos,
owing to the impossibility of adding forms identical
with those existing in the natural product. That is,
the total content of nitrogen in a rectified guano may
be the same as in the genuine product, though the
special forms and their proportions cannot be simulated.
The distinctive value of the natural guanos is due to
the fact that the nitrogen existed in a number of dif-
ferently soluble compounds, which became available at
different times in the soil, and thus constantly fed the
plant with this element. The fact that nitrogen guanos
gave such good results, is an evidence of the advan-
tage of introducing different forms into artificial
mixtures,
It is argued that because of the very great value of
NATURAL GUANOS 49
guanos, which consist very largely of the excrement
of fowls, that droppings of pigeons, particularly, and
of domestic fowls should also possess a high value,
and for this reason a rather fictitious value has been
fixed upon these products. These products differ very
materially from natural guanos, and it is due probably
both to the character of the food eaten by the domestic
fowl, and to the different methods by which the
material is obtained. The birds producing the guanos
feed largely upon fish, a highly nitrogenous food,
resulting in an excrement richer in this element than
that from the domestic bird, feeding largely upon
vegetable matter; and, besides, the former were accu-
mulated in a hot, dry climate, which quickly absorbs
the moisture contained in the fresh droppings, thus
leaving it in a much drier state than is the case with
the domestic product.
It will be observed from the foregoing brief de-
scription of the chief sources of organic forms of
nitrogen, that a very wide variation occurs both in
the composition or content of nitrogen in these pro-
ducts, and in the availability of their nitrogen, or
rapidity with which, under similar conditions, it is
given up to plants. The fact that a substance contains
nitrogen in considerable amounts and in an organic
form, then, is not a sufficient guide as to its usefulness.
Its mechanical condition, or physical form, must also
be taken into consideration, and, other things being
equal, the tougher and denser the substances, the
longer the time required to decay, and hence the more
slowly will the material feed the plant.
D
5O FERTILIZERS
AMMONIA COMPOUNDS
As already stated, nitrogen does not feed the plants
in organic forms; it must first decay. The first pro-
duct of the decay of a nitrogenous organic substance
is ammonia, a combination of two elements, hydro-
gen and nitrogen. As the organic animal or vege-
table substance which contains carbon, hydrogen, oxy-
gen and nitrogen in combination breaks up, the car-
bon combines with part of the oxygen to form
carbonic acid; part of the hydrogen also combines
with oxygen to form water, and the nitrogen combines
with hydrogen to form ammonia. Yet even in this
form, plants do not absorb it freely. Ammonia is in
a better form than the organic material, because, in
the first place, it is soluble in most of its combina-
tions with other substances, and is thus readily dis-
tributed in the soil, and in the second place, it is
very lable to change. That is, its future availability
is no longer dependent upon any mechanical or phys-
ical form; every portion or pound of ammonia is as
good as any: other portion or pound. Ammonia,
however, does not occur as a natural product, like
the organic forms, blood, meat and fish. Commercial
forms are the result of a manufacturing process, and
they may exist as distinct chemical substances, as
sulfate of ammonia, in which ease the ammonia is
combined with sulfuric acid; as chlorid of ammonia,
in which ease it is combined with hydrochloric
acid; as nitrate of ammonia, in which ease it is
combined with nitric acid; and as carbonate of am-
SULFATE OF AMMONIA 51
monia, in which case it is combined with carbonic
acid.
Sulfate of ammonia is the only one of these com-
pounds which can be now obtained at a sufficiently
low cost to encourage its use as a fertilizer. Sulfate
of ammonia is a chemical salt which, when pure,
contains 21.2 per cent of nitrogen. In commercial
forms, however, it usually contains about 20 per cent
of nitrogen, and even this makes it the richest in
nitrogen of any of the commercial nitrogenous pro-
ducts. That is, every ton contains 400 pounds of
nitrogen, and is thus richer by 60 pounds per ton
than nitrate of soda, the next highest grade nitrog-
enous product. Sulfate of ammonia is obtained from
the dry distillation of animal bone in the manufacture
of bone-black, from the distillation of coal in the
manufacture of illuminating gas, and from coal in
the manufacture of coke. The quantity now made is
increasing annually, largely because of the improved
methods used in the manufacture of coke, which per-
mit the saving of the ammonia. The cost of nitrogen
in this form is likely to be so much reduced in
future as to encourage its very considerable use by
fertilizer manufacturers. Its chief advantages are that
it is very concentrated, therefore reducing the cost
of handling; it is always in the same form, a distinct
and definite product, thus rendering its purchase a
safe proceeding; and it is very quick to act, thus
making it a very useful form, especially for quick-
growing crops. Its physical character is such as to
permit its ready distribution in a mixture.
52 FERTILIZERS
NITRATE NITROGEN
As previously stated, neither organic nor ammonia
compounds containing nitrogen are capable of fully
meeting: the demands of plants for this element. The
first, or organic nitrogen, must pass through two
changes, first to ammonia, and then to nitrate, and
the ammonia must change to a nitrate. The nitrate is
directly absorbed by plants, and the larger portion
obtained by them is taken up in this form. Hence,
from the standpoint of availability, nitrate nitrogen
must be regarded as the most useful form. Like
ammonia, too, a pound of it is as good as any other
pound, from whatever product it may have been de-
rived. It is a relatively concentrated material; and
as it is perfectly soluble, it readily distributes itself
everywhere in the soil to which it may be applied.
Nitrate of soda.—Although nitrogen as nitrate is
not generally distributed as a natural product, vast
deposits of erude nitrate of soda are found in the
rainless districts of South America. -These erude salts
contain from 4 to 10 per cent of nitrogen, which are
dissolved and re-crystallized before they are put upon
the market, in order to remove as far as possible the
impurities which are associated with them. The chem-
ically pure salt, nitrate of soda, contains 16.47 per cent
of nitrogen, and the commercial article, called “Chili
saltpeter,” contains from 15.5 to 16 per cent. The
impurities which remain in it consist mainly of sodium
chlorid, or common salt, which, together with moisture,
causes a lower percentage in the commercial product.
AVAILABILITY OF NITROGEN 53
THE RELATIVE AVAILABILITY OF THE DIFFERENT
FORMS OF NITROGEN
From this discussion of the kind and source of
nitrogenous fertilizer supplies, it is shown that the
form of the nitrogen is an important factor in
determining the rate at which the plants may obtain
it. In the ease of nitrate, the form is such as to
enable the plants to take it up immediately. It is,
therefore, theoretically the best, because as soon as
it comes in contact with the roots, it is absorbed by
them; there is no appreciable time required to enable
the element to get into a condition to be taken up.
Furthermore, its extreme solubility makes it possible,
-when moisture conditions are good, to reach every
portion of the soil in which the roots are located, so
that it is not only more available by virtue of its being
in the right form, but because it readily goes to the
place where the plant roots are. The next substance
in order of availability is ammonia, and the rapid-
ity with which ammonia will change to a nitrate
makes it under many circumstances quite as useful.
It possesses, too, one great advantage possessed by
the nitrate, that of being soluble in water, and thus
readily distributing itself throughout the surface soil.
The difference in usefulness of these two forms seems
to depend more largely upon the character of the
season than upon the exact form. In a very wet
season the nitrate is less useful, because liable to be
washed below the reach of the roots, or lost alto-
gether, and in a dry season it is more useful than
54 FERTILIZERS
the ammonia, becausé as soon as it is in solution it is
eapable of being absorbed. It must be remembered,
however, that these two forms possess the further
advantage over organic forms, that they are definite
chemical compounds, which always possess the same
characteristics, and under similar conditions they always
act in the same way. If nitrogen is purchased as am-
monia, the source of the nitrogen is not important;
that is, whether derived in the manufacture of bone-
black, or of illuminating gas, or coke, if it 1s ammonia,
it is identical in its character. The same is true of
nitrate—the original source of the nitrogen is imma-
terial.
The availability of organic forms, as already pointed
out, depends upon the rapidity with which they will
change to the nitrate form. Such products as dried
blood, dried meat, dried fish and concentrated tank-
age change rapidly, and are, therefore, good forms,
while products lke raw leather and horn meal are
very slow to change.
The practical point, and the one of prime impor-
tance to the farmer, is, then, to know how to estimate
the relative value or usefulness of these different pro-
ducts, what is the rate of availability as compared
with nitrate, and thus the relative advantage of
purchasing the one or the other, at the ruling market
prices. Relative values, however, cannot be assigned
as yet, though careful studies of the problem have
been made, chiefly by what are known as “vegetation
tests,” that is, tests which show the actual amounts of
nitrogen that plants can obtain from nitrogenous pro-
lad
TESTS OF AVAILABILITY 5)
ducts of different kinds, when they are grown under
known and controlled conditions. The results so far
obtained, while only serving as a guide, indicate that
when nitrate is rated at 100 per cent, blood and
cotton seed meal are about 70 per cent, dried and
ground fish and hoof meal 65 per cent, bone and
tankage 60 per cent, and leather, ground horn and
wool waste range from as low as 2 per cent to as
high as 30 per cent. These figures furnish a fair
basis for comparing the different materials, when used
for the same purpose or under the same conditions.
If, for example, the increased yield of oats due to the
application of nitrate of soda is 1,000 pounds, the
yield from blood and cotton-seed meal would be 700
pounds, the yield from dried ground fish and hoof
meal would be 650 pounds, from bone and tankage
600 pounds, and from leather, ground horn, and wool
waste, from 20 to 3800 pounds.
Conditions Which Modify Availability
These figures alone are, however, not a sufficient
guide as to the kinds to buy under all conditions,
since the usefulness of the different forms are again
dependent upon such other conditions as the kind of
crop, the season, and the object of the application.
The kind of crop is an important factor, since certain
crops grow and develop quickly, while others grow for
a comparatively long period; the season, because the
changes from organic forms to ammonia, or nitrate,
only take place when the temperature reaches 37° F.,
56 FERTILIZERS
and when in addition sufficient moisture is present.
Hence, a material which might give excellent results
when applied to a crop that grows through a long
period in a climate where the season is very warm
and moist, might be very unsatisfactory where the
season is short, cold and dry. These are a few of
the conditions which modify the rate of the decay of
the same material.
The object of the application should also be taken
into consideration. The rate of the feeding of the
plant with nitrogen in organic forms is measured by
the rate of decay of the organic material containing
it, while when nitrate is used, its feeding is direct.
The result is really a sort of feeding of the soil in
the one case, and a direct feeding of the plants in the
other. Where the purpose is to get the largest pro-
portionate increase in crop from the least amount
applied, either the nitrate, or the ammonia, or the
more active of the organic forms, would be likely to
give the best returns. Whereas, if the object to be
attained is not so much a large increased crop as it
is increase in’ the future productive capacity of the
soil in respect to this element, the slower-acting ma-
terials will often answer the purpose quite as well as
the use of the more active nitrate form, as in this
form no insoluble combinations are formed, the
nitrate is freely movable, and if the plants do not
absorb it, and heavy rains come, the water contain-
ing the nitrate is carried through the soil into the
drains and the nitrogen lost. The disadvantage of
the nitrate is, then, that there is a greater possibility
CONDITIONS WHICH MODIFY AVAILABILITY 57
of loss from its use than from the use of materials
which are either insoluble, or which are readily ab-
sorbed. The ammonia, while perfectly soluble, is fixed
by the other substances in the soil, and is not, there-
fore, readily leached out, though if heavy applications
are made the possibility is increased, because of the
rapid change of the ammonia into the nitrate form.
In the ease of organic materials, the losses from
leaching are seldom worthy of consideration in good
practice, since an appreciable time is required, even
in the ease of the best forms, to change all of the
nitrogen into ammonia, and then to a nitrate; while
in the case of the poorer forms, still more time is
necessary to cause the change, and losses are not
liable to occur. In the making up of fertilizers, all
of these considerations should be carefully balanced,
and it is the practice on the part of many manufac-
turers to use a part of each of the three forms, so
that a continuous feeding of the plant may be in-
sured. Therefore, while the fact remains that fer-
tilizers containing only the one form may not be the
poorest, the chances are that those which contain all
forms are likely to give more satisfactory results.
CHAPTER IV
PHOSPHATES— THEIR SOURCES, COMPOSITION AND
RELATIVE VALUE :
Many farmers apply the term “phosphate” to all
manufactured fertilizers, without regard to the kind
and character of the fertilizing constituents con-
tained in them. The term “phosphate” should only
be applied to materials which contain phosphoric
acid, and it does not necessarily imply that the
phosphoric acid is in an available form. The term
“superphosphate” implies that the phosphoric acid
contained in the material is available. The phos-
phates constitute a class of products from which
superphosphates are made, and which are used in the
manufacture of fertilizers that contain iminediately
useful or available phosphoric acid. The following
discussion of phosphates is quoted from the author’s
“First Principles of Agriculture :” *
The phosphoric acid in artificial manures is derived
from compounds ealled “phosphates.” In phosphates
the phosphoric acid is united with lime, iron and
alumina, forming phosphates of lime, iron and
alumina, as the ease may be. The phosphates of
*« Birst Principles of Agriculture.” Silver, Burdett & Co., Boston, 1896. The
quotation comprises the entire discussion preceding **Phosphates as Sources of
Phosphoric Acid to Plants,” except * Bone Tankage” and “Tennessee Phosphate.”
(58)
PHOSPHATE OF LIME 59
lime are better calculated for the purpose, and are,
therefore, used more largely than any other as a
source of phosphoric acid, in the manufacture of
artificial manures.
The phosphates available for this purpose are not,
however, pure salts, but exist in combination either
with organic substances, or with minerals, or both,
the content of phosphoric acid and its combination
with other substances determining the usefulness of
the phosphate to the manure-maker.
The phosphorie acid in these materials is soluble
with difficulty in the soil water; and hence in their
original condition, or in the erude raw forms, they
give up this element in proportion as they decompose
or decay in the soil. Those in combination with
organic substances, either animal or vegetable, are,
as a rule, more quickly useful as a source of phos-
phorie acid than those composed entirely of mineral
constituents.
PHOSPHATE OF LIME, OR BONE PHOSPHATE —
ANIMAL BONE
The bones of animals are the chief source of phos-
phates that exist in combination with organic matter,
and were for a long time the main source for
manurial purposes.
Bone consists chiefly of three classes of sub-
stances; viz., moisture, organic matter, containing
nitrogenous and fatty matter, and phosphate of lime,
or bone phosphate—the proportion, particularly of
60 FERTILIZERS
the nitrogen and phosphoric acid, depending upon
the kind of bone and the method of its treatment.
Bone from the same kind of animal differs in
composition according to the age of the animal and
its location in the body. In a general way, the
younger the animal the softer the bone, the poorer in
phosphate of lime and the richer in nitrogen; the
older the animal, the richer in phosphate of lme and
the poorer in nitrogen. The large and hard thigh
bones of an ox, for instance, differ in composition
from the softer and more porous bones of other parts
of the body.
The phosphate of lime of the harder bones is
dense and compact; that from the softer bone is
more open and porous. The chief cause of variation
in the composition of bones used as manure, how-
ever, is due to the treatment they receive. This is
recognized by manufacturers and dealers, and differ-
ent names of brands are used to indicate the method
of manufacture or treatment. As applied, however,
they do not always correspond to the methods of
treatment.
Raw Bone
The term “raw bone” is properly applied to bone
that has not suffered any loss of its original econ-
stituents in the processes of its manufacture, and is
for this reason highly regarded by farmers, who
believe that it is purer than any other form. This is
true in a large measure, though the fact that it is
ANIMAL BONE 61
raw bone is not altogether an advantage from the
standpoint of usefulness. Raw bone too often con-
tains considerable fatty matter, which makes it a diffi-
eult process to grind it fine, and which also has a
tendency to retard the decay of the bone in the soil.
A considerable amount of fat also reduces propor-
tionately the percentage of the valuable constituents,
phosphoric acid and nitrogen. Good raw bone, free
from meat and excess of fat, should contain on the
average 22 per cent of phosphoric acid and 4 per cent
of nitrogen.
Fine Bone
The trade terms “bone meal,” “bone dust,” and
“fine bone,” are used to indicate mechanical condi-
tion, or fineness of division, and do not refer
especially to composition. These names should not
be taken as indicating the fineness without personal
examination, since frequently the products do not, in
this respect, correspond to the name. .
Boiled and Steamed Bone
The larger portion of the bone used as manure
has been boiled or steamed for the purpose of freeing
it from fat and nitrogenous matter, both of which
are products valuable for other purposes. The fat is,
of course, of no value as a manure, and its absence
is an advantage. The nitrogen, while useful as a
manure, is extracted chiefly for the purpose of making
glue and gelatine.
62 FERTILIZERS
By boiling or steaming, the bone suffers a loss of
its original constituents, the chief result of which is
to change the proportions of the nitrogen and phos-
phorie acid contained in it. Steamed or boiled bone
contains more phosphorie acid and less nitrogen than
raw bone, and is also more variable in composition,
the relative percentage of these constituents depending
upon the degree of steaming or boiling to which the
bone has been subjected.
Bone that has been used for the purpose of
making glue, where the chief object is to extract the
nitrogenous matter, contains from 28 to 30 per cent
of phosphoric acid and from 1% to 1% per cent of
nitrogen. The steaming of bone, particularly when
conducted at high pressure, also exerts a favorable
effect upon the physical and mechanical character of
the bone. It destroys its original structure, makes
it soft and crumbly, and often reduces it to a finer
state of division than can be readily accomplished by
erinding;, and, since it is also free from fat, and is
finer, it is more directly useful as a source of phos-
phorie acid to plants than purer raw bone.
In some eases, the fat is extracted from bone by
means of such solvents as petroleum or benzine.
These methods of extracting the fat have the ad-
vantage of increasing the relative proportion of
the nitrogen, this element not being attacked by
the solvents. The more complete extraction of the
fat and moisture by these methods also aids in
the final preparation of the bone by grinding. Bone
prepared in this way frequently contains as_ high
TANKAGE 63
as 6 per cent of nitrogen and 20 per cent of phos-
phoric acid.
The nature and composition of animal bone is
such as to make it a valuable source of phosphoric
acid; and, while it is largely used with nitrogenous
and potassic materials in the manufacture of artificial
manures, its best use is, perhaps, in the fine ground
form, particularly for soil improvement and. for slow-
growing crops.
Phosphoric acid applied in this form gradually
gives up nitrogen and phosphoric acid to the plant;
and its physical and chemical characteristics are such
that it forms in the soil, during the growing season,
no compounds more insoluble than the bone itself.
Of all the phosphatic materials available as manure,
bone is the only one that is now used to any extent
without further treatment than simple grinding.
Bone Tankage
As already intimated in the discussion of nitrog-
enous materials, certain products valuable for nitro-
gen also contain considerable amounts of phosphoric
acid. Among these, tankage is the most important,
and six definite grades are now recognized in the
trade —the richest containing as high as 18 to 19 per
cent of phosphoric acid, or equivalent to 40 per cent
bone phosphate; the second containing 16 per cent
phosphoric acid, equivalent to 35 per cent of bone
phosphate; the third containing 13% per cent of
phosphoric acid, or equivalent to 30 per cent of bone
64 FERTILIZERS
phosphate; the fourth, 11% per cent of phosphoric
acid, or equivalent to 25 per cent of bone phosphate ;
the fifth, 9 per cent phosphoric acid, or equivalent to
20 per cent bone phosphate, and the sixth contain-
ing about 7 per cent phosphoric acid, or equivalent to
15 per cent bone phosphate.
It will be observed that certain grades of tankage
approach the composition of bone in their content of
phosphoric acid; the nitrogen increases as the phos-
phorie acid decreases, as already pointed out in the
discussion of nitrogenous materials. Since tankage
is made from the residue remaining in the tanks
used for boiling cattle heads, feet, clippings, and other
refuse animal matter, it may be classed with boiled
bone in reference to the quality of its phosphoric
acid. Its agricultural value is further modified by the
fineness to which it is ground; it is frequently sub-
stituted for bone in the manufacture of fertilizers,
where phosphate derived from bone is regarded as an
important constituent of the mixture or brand.
Other Organic Products
There are also other products which should not
be disregarded in a discussion of phosphates, though
because of their content of other constituents they are
primarily valued for them, rather than for the phos-
phorie acid. A good example is the dried ground
fish, which often contains as high as 8 per cent of
phosphorie acid, or an equivalent of 17 to 18 per cent
of bone phosphate of lime. The phosphoric acid in
BONE - BLACK 65
dried fish is frequently more available than in other
organic forms, owing to the fact that in the drying
of the scrap it is often necessary to add sulfuric acid
to prevent putrefaction. On the average, more than
one-half of the total phosphoric acid in this product
is in an available form.
The phosphorie acid contained in other nitrogenous
products, as cotton-seed meal and eastor pomace,
while not large, is of some importance, as it is rela-
tively more available than in raw bone or in tankage.
Bone-black, or Animal Charcoal
This material becomes an important source of
phosphoric acid for artificial manures, after it has
served its chief and first purpose in clarifying sugar.
In making bone-black, only the best bones are used ;
they are cleaned and dried, and placed in air-tight ves-
sels, and heated until all volatile matter is driven off ;
the resultant product, which retains in part the original
form of the bone, is then ground to a coarse powder ;
it then becomes a bone charcoal, consisting chiefly of
earbon and phosphate of lime, though also containing
small amounts of magnesia and earbonate of lime.
Bone-black, as received from the refineries, con-
tains the impurities gathered there, consisting chiefly
of vegetable matter and moisture. It is somewhat
variable in composition, containing from 32 to 36
per cent of phosphoric acid and a small amount of
nitrogen. It decays slowly in the soil, and is not now
used to any extent directly as a manure.
E
66 FERTILIZERS
Bone-Ash
Bone-ash is an excellent, though not large, source
of phosphoric acid. It is exported in considerable
quantities from South America, where the bones are
burned and the bulk reduced, in order to facilitate
transportation. It does not contain nitrogen, and is
more variable in composition than bone-black, though
usually somewhat richer in phosphate of lime. Good
samples contain from 27 to 386 per cent of phos-
phorie acid.
Bones themselves, and the phosphates derived
from bones, constitute a class differing from other
phosphates used in making manures, in that they are
derived directly from organic materials and, as a
class, they possess characteristics, due to this fact,
which render them more useful than those derived
from purely mineral sources.
MINERAL PHOSPHATES
These constitute a class of products differing from
those of immediate or recent animal origin mainly in
the fact that they are not combined with organic mat-
ter, and are more dense and compact in their struc-
ture. They occur in several different forms, and are
procured from distinet sources.
South Carolina Rock Phosphates
These are found both on the land and in the beds
of rivers in the vicinity of Charleston, S. C., and are
SOUTH CAROLINA ROCK PHOSPHATES 67
sometimes called “Charleston phosphates.” The de-
posits vary in thickness from one to twenty feet,
through which the phosphate is distributed in the
form of lumps or nodules, ranging in weight from an
ounce to over a ton. These nodules are irregular,
non-crystalline masses, often full of holes, which con-
tain clay or other non-phosphatic materials. That
obtained from the river is called “river phosphate,”
or “river rock;” and that from the land, “land phos-
phate,” or “land rock.” The two varieties do not
differ materially in composition, particularly in the
eontent of phosphoric acid.
The rock contains from 26 to 28 per cent of phos-
phorie acid. Its uniformity, in connection with the
fact that it contains but small percentages of com-
pounds of iron and alumina, minerals which prevent
its best use by the manufacturer, make it a highly
satisfactory source of phosphoric acid.
The river rock is secured by dredging; that from
the land is largely dug. In either case it is washed
to remove the adhering matter, and then dried, when
it is ready for grinding or shipment. South Carolina
rock phosphate, when very finely ground, is called
“floats.” It is sometimes used upon the land in this
form, and when used for certain crops, as turnips, for
example, and on certain soils, notably those wet and
heavy and rich in vegetable matter, very satisfactory
returns are obtained.
These deposits were first worked in 1868, though
the presence of phosphate at this point was known at
a much earlier date.
68 FERTILIZERS
Florida Phosphates
The presence of phosphate in commercial quanti-
ties in Florida was discovered in 1888, since which
time very great progress has been made in developing
the deposits. The deposits occur in a number of
forms, — first, “soft phosphate,” a whitish product,
somewhat resembling clay, and largely contaminated
with it; second, “pebble phosphate,” consisting of
hard pebbles, occurring both in river beds and upon
the land, and mixed with other materials; and third,
“rock,” or “bowlder phosphate,” which occurs in the
form of stony masses or bowlders, both large and
small. These three forms also differ widely in com-
position, both in reference to their content of phos-
phorie acid and in respect to the presence of other
minerals.
The soft phosphate is the poorest in phosphoric
acid. It is easily prepared, and is largely used directly
upon the land. It is also the most variable in com-
position, ranging from 18 to 380 per cent. The pebble
rock is also variable in composition, though; when
washed free of sand and elay, it is richer in phos-
phorie acid than the soft variety. Good samples con-
tain as high as 40 per cent and over of phosphoric
acid. The bulk of the “Florida phosphate” is be-
heved to exist in the pebble form.
The rock or bowlder phosphate, though apparently
much less in amount, is more uniform in composition,
and is- much richer than either of the other forms.
The clean, dry bowlder phosphate often contains as
OTHER MINERAL PHOSPHATES 69
high as 40 per cent phosphoric acid, far exceeding in
richness the South Carolina rock superphosphate.
Canadian Apatite
This material is a crystallized rock of true mineral
origin, and occurs associated to a greater or less ex-
tent with other materials. It is, therefore, not uni-
form in character, the phosphoric acid varying
according to the amount of the other substances
present.
It is mined in the provinces of Quebee and Onta-
rio, and separated into various grades at the mines.
The mining is expensive, and the necessity for grad-
ing in addition makes the cost of production propor-
tionately high. The highest grade of this phosphate
is very pure, containing 40 per cent of phosphoric
acid.
Tennessee Phosphate
The phosphate deposits in Tennessee were discoy-
ered in November, 1894, since which time they have
been exploited and a rapid development made. This
phosphate differs from the phosphate of South Caro-
lina and Florida in that it does not exist as nodules,
pebbles or bowlders, but in veins and pockets, and,
therefore, does not need to be washed and dried
previous to its treatment. While the phosphates from
the various deposits are not uniform in their com-
position, it is possible to secure large quantities that
70 FERTILIZERS
equal or exceed 30 to 32 per cent of phosphoric acid,
or 70 per cent or over of bone phosphate, and that
are relatively free from deleterious substances, thus
making them not only a rich but a valuable source
of supply for the manufacturers of superphosphates.
Iron Phosphate, or Thomas Phosphate Powder
This is a waste product from the manufacture of
steel from phosphatic iron ores, by what is known
as the “basic process.” It is sold under several
names, as ‘Thomas phosphate meal,” ‘ phosphate
slag,” “basie slag,” and “odorless phosphate.” It
is produced in large quantities in England, France
and Germany, and in those countries is not only one
of the cheapest sources of phosphoric acid, but is
regarded as a very valuable product. It contains
from 15 to 20 per cent of phosphoric acid in the
form of phosphate of lime, in connection with large
amounts of lime and oxide of iron. It is used almost
altogether in the form of a fine powder, since it is
not suitable for the purposes of the: manufacturer.
Phosphatic Guanos
Previous to the discovery of the phosphates in
South Carolina, these guanos were a very important
source of phosphoric acid. They are now but little
used in this country. They are obtained from the
rainless districts of the world, chiefly from the islands
bordering the coast of South America and from the
West Indies, They are derived from the excrements
PHOSPHATES AS FERTILIZERS i
of birds, and frequently include considerable organic
matter containing nitrogen.
The Peruvian guano of earlier times was particu-
larly rich in the best forms of nitrogen. The purely
phosphatic guanos are rich in phosphorie acid, and are
excellent materials. Like the iron phosphate, they are
not suitable for the manufacture of artificial manures.
PHOSPHATES AS SOURCES OF PHOSPHORIC ACID
TO PLANTS
The phosphates mentioned constitute what are called
“raw materials,” and, with the exception of bone, are
not largely used directly, or without further treatment
to render the phosphoric acid more soluble, and thus
more immediately available to plants. As already
stated, the phosphoric acid in them becomes food in
proportion to the rapidity of decay, which is influenced
both by the character of the material and the fineness
of its division. Fine materials, too, permit of a more
even distribution, thus bringing more particles of
phosphate in contact with the roots of plants.
As already stated, a phosphate is a substance in
which the phosphoric acid is combined with lime, iron
or alumina. The phosphates of lime are the only ones
that are used to any extent in the manufacture of arti-
ficial fertilizers. The phosphoric acid contained in
animal bone is in the form of phosphate of lime,
hence the term “bone phosphate of lime” has been
applied to all phosphates that contain their phosphoric
acid as phosphate of lime. In fact, statements of
F ip FERTILIZERS
analysis of iron and alumina phosphates are frequently
expressed in terms of phosphate of lime. That is,
the content of phosphoric acid is stated as equivalent
to a certain percentage of bone phosphate, the term
expressing the total amount of combined phosphoric
acid; as, for example, a bone which contains 20 per
cent of phosphoric acid, which is the average content
in good bone, is equivalent to 48.60 per cent of phos-
phate of lime.
All phosphates are insoluble in water, but, as
phosphates, they are not capable of feeding the plant
directly; they must first decay. Hence, the useful-
ness of a phosphate depends upon the rate of decay,
or time required to change to such a form as to be-
come available to the plant. The rapidity with which
a phosphate will feed the plant depends upon a num-
ber of conditions, chief among which are, first, the
character of the substance itself; second, the fine-
ness of its division; third, the character of the soil
to which it is aes and fourth, the kind of crop
for which it is used.
The Influence of Source of Phosphate Upon
Availability
The chief point to be observed in the first case,
is whether the substance is animal or vegetable, or
whether it is mineral. Phosphates of immediate
animal or vegetable origin decay more rapidly than
purely mineral phosphates, because of the greater
tendency of the organic matter with which the phos-
AVAILABILITY OF PHOSPHATES 73
phate is associated to respond to the action of the
natural agencies which cause decay. A _ bone, for
example, if kept in a suitable condition of moisture
and warmth, will soon begin to rot, the rotting
affecting not only the animal matter, but more or
less the phosphatic matter with which it is so
closely identified, the fermentation primarily attack-
ing the organic substances, but exercising a greater
or less solvent effect upon the phosphates.
In the case of the mineral substances, the rate of
decay is usually much slower, because there is no
organic fermentation. The material changes or is~-
broken up only by virtue of the action of the natural
solvents, air and water, and solvent substances in the
soil. Furthermore, the phosphate of the animal bone
is always a phosphate of lime, which, while not
soluble, is in itself more readily attacked by the
natural agencies than a mineral phosphate which has
associated with the bone phosphate other minerals
that are not readily attacked by those agencies. That
is, the mineral phosphates, while they are made up
chiefly of phosphate of lime, are associated with other
minerals, as iron and alumina, that are more slowly
attacked than the phosphate of lime itself, and to
some extent, too, prevent the full effect of the sol-
vents, rathér than encourage their action, as is the
case with bone.
Influence of Fineness of Division
In the second place, fineness of division has an
important bearing upon availability, since the finer
74 FERTILIZERS
the substance is ground, the greater will be the sur-
face area exposed to the natural agencies which cause
decay. Thus the application of a coarsely ground
phosphate may not show any results the first season,
while the same substance ground to a powder may
have a good effect the first season; that is, its fine-
ness permits of the solubility of a considerable portion
of its phosphoric acid. |
The Character of Soil as a Factor Influencing
Availability
In the third place, the kind of soil to which the
phosphate is applied may influence the rate at which
the plants may obtain it. A soil which is open and
porous, and thus permits the free access of air and
circulation of water, and one which contains a large
portion of other matter capable of decay, vegetable or
animal, presents more favorable conditions for the
solubility of phosphates than one which is close and
compact in texture and purely mineral in its charac-
ter, thus preventing the free access of air and water,
and in which no organic changes are taking place.
In the one case the conditions are such as to favor
the action of the natural agencies, and in the other
they are such as to retard their action.
Influence of the Kind of Crop
In the fourth place, the value or usefulness of
phosphates is measured to some extent by the charac-
AVAILABILITY OF PHOSPHATES 75
teristics of the plant or crop to which they are ap-
plied. Plants differ in their power of acquiring food.
Certain plants are able, because of their peculiar root
system, or period of growth, to appropriate food more
readily from insoluble sources than others.
General Considerations
All these considerations must be observed in
determining the usefulness of a phosphate. It is
believed by experienced farmers, though not abso-
lutely confirmed by experimental inquiry, that animal
bone, for example, is far superior, as a source of
phosphoric acid, for most crops, to the mineral phos-
phates, though both may be ground to the same
degree of fineness; and also, that the finer the
bone is ground, the more rapidly will it give up its
phosphoric acid.
Laboratory tests show that the phosphoric acid in
bone, while insoluble in water, may be partly dis-
solved at a certain temperature by a neutral solution
of ammonium citrate. This medium is used to de-
termine what is called “available” in other phos-
phatie products. The rate of solubility in this medium
is measured by the method of preparation of the bone
and its fineness, the phosphate in raw bone meal of
the same fineness showing rather a lower rate of
solubility than the phosphates in steamed bone. The
phosphate in the finest steamed bone is much more
soluble than that in the coarser grades. This measure
of the rate of solubility of bone, while not, perhaps,
76 FERTILIZERS
showing the exact rate at which the plants may
obtain it, is a fairly safe guide in its use for most
crops, as compared with those mineral phosphates
which are not perceptibly soluble in this medium.
The range of solubility of different kinds and grades
of bone is from 20 to 75 per cent, and the average
of a large number show about 30 per cent soluble
in citrate of ammonia, which would be called “avail-
able” if found in mixed fertilizers, and probably can
be as safely depended upon as the available shown
in other products.
In any ease, animal bone, or finely ground mineral
phosphates, cannot be depended upon to fully meet the
needs of quick-growing crops for phosphoric acid, but
may answer an excellent purpose where the object is
to gradually improve the soil in its content of this
constituent, as well as to supply such crops as are
continuous, or that grow through long periods, as,
for example, meadows, pastures, and orchard and
vineyard crops.
As to the specific substance, the iron phosphate,
or Thomas phosphate powder, experiments in Europe
have shown that it possesses a higher rate of availa-
bility than other phosphates which are insoluble in
water, but which show the same rate of solubility
in ammonium eceitrate, though its solubility, or
availability, is measured to some extent by the degree
of fineness to which it is ground; and it is believed
that its special form, the tetra-calcic, also exercises a
considerable influence upon the rate of availability.
European vegetation and field experiments show
AVAILABILITY OF PHOSPHATES T7
pretty clearly that two parts of phosphoric acid from
the Thomas phosphate powder are approximately
equivalent to one part from soluble phosphoric acid,
and that this phosphate is especially useful on wet,
marshy soils and those poor in lime. Experiments
conducted in this country practically confirm these
conclusions.
The relative availability of the phosphates in the
natural guanos has also been shown to be somewhat
higher than in other insoluble phosphates. These
latter substances for this reason possess a distinct
value over others for certain classes of crops, as, for
example, cranberries, where the soluble phosphates
would be liable to be washed out, and where the
organic phosphates would be liable to float on the
,surface of the water, and also where lands are cold
and sour, and not readily fermentable.
The practical point, however, to the farmer, is the
amount of increase that he may obtain from a certain
definite expenditure, a matter which will be discussed
later, in the discussion of the use of fertilizers for the
various crops.
CHAPTER V
SUPERPHOSPHATES —POTASH
THE different phosphates mentioned in the _ pre-
vious chapter constitute the sources of supply for
the manufacture of commercial fertilizers. That is,
with the exception of animal bone, Thomas _ phos-
phate powder and natural guanos, they are used more
extensively for this purpose than directly on the land
in their raw state. They are the raw materials from
which the manufactured phosphatic fertilizers are de-
rived. ‘The purpose of the manufacture is to con-'
vert them into a form in which the phosphoric acid is
immediately available, and thus directly useful to the
plant. The term “available” in this case is used in the
Same sense as in the discussion of the forms of nitro-
gen (Chap. iii.), and it means that when the phos-
phoric acid is in this form, the plants may acquire it
immediately.
INSOLUBLE PHOSPHORIC ACID
Phosphate of lime is, chemically speaking, a salt
capable of existing in various forms, the form measur-
ing in large degree the rate of availability. The
phosphate of lime, as it exists in the animal bone and
mineral phosphates, for example, consists of three
(78)
FORMS OF PHOSPHORIC ACID 79
parts of lime and one of phosphoric acid. This is
the insoluble form. It is not immediately available,
and because of the three parts of lime to one of
phosphoric acid, which it contains, it is also called
tricalcic, tribasic, or bone phosphate, and is graph-
ically expressed in the accompanying formula:
Lime
Lime ~ Phosphorie Acid
Lime
That is, in each molecule, however small, there are
three parts of lime and one part of phosphoric acid.
SOLUBLE PHOSPHORIC ACID
In another form, the phosphate consists of one part
of lime and one of phosphoric acid, two parts of the
lime in the tricaleic form being replaced with water.
This form is called monobasic, or monocealeic. It is
a saturated phosphate. There could be no less than
one part of lime to one of phosphoric acid, and such
phosphates are called acid phosphates, or superphos-
phates. The combination of the lime and phosphoric
acid may be shown as follows:
Lime
Water Phosphorie Acid
Water
This form is completely soluble in water and im-
mediately available, and when applied to the soil
readily distributes itself everywhere, thus making it
more useful than any other form.
80 FERTILIZERS
REVERTED PHOSPHORIC ACID
Another form of phosphate consists of two parts
of lime and one part of phosphoric acid, and is called
dicalcic, dibasic, or reverted, One part of the lime
in the insoluble is replaced by an equivalent of water,
and is expressed as follows:
Lime :
Lime Phosphorie Acid
Water
The reverted form, which means a going back from
the soluble toward the insoluble form, is also insoluble ,
in water, but is readily soluble to the roots of plants.
It was formerly supposed that these three were
the only forms in which phosphoric acid existed, but
another form, in which four parts of lime are com-
bined with one of phosphoric acid, and thus ealled
tetrabasic, or tetracaleic, has been found quite re-
cently to exist in the Thomas phosphate powder:
Lime
Lime
Lime
Lime
Phosphoric Acid
This form is insoluble in water, though it has
been found to be more available than the insoluble
tribasie form.
HOW SUPERPHOSPHATES ARE MADE
Any material which contains a high content of the
tricaleic or bone phosphate, 60 per cent or over, is
THE MANUFACTURE OF SUPERPHOSPHATES 8]
suitable for the manufacture of superphosphates, pro-
vided it does not possess a too high content of dele-
terious substances. In the manufacture of superphos-
phates, the phosphate is first ground to a fine powder,
then mixed with sulfuric acid. The acid dissolves the
phosphate, and two parts of the lime which are com-
bined with the phosphoric acid in the tricalcic form
are first set free, and then combined with the sulfuric
acid, making a superphosphate (monocalcic), and a
sulfate of lime or gypsum. That is, in this process,
two of the three parts of the lime combined with the
phosphoric acid to form the insoluble phosphoric
acid, are removed, thus leaving one part of the lime
combined with the phosphoric acid, making the super-
phosphate. A pure superphosphate is, therefore, a
mixture of soluble phosphate and of sulfate of lime
or gypsum.
The Difference in the Superphosphates made
from the Different Materials
In the early use of superphosphates, the chief raw
material was animal bone. The superiority of the
bone superphosphate, or dissolved bone, as it was
ealled, over the raw bone, was manifest at once, and
the familiarity with genuine bone superphosphates
thus early acquired by farmers was, perhaps, quite
as influential as any other in creating a prejudice in
favor of their continued use in preference to super-
phosphates derived from mineral phosphates. The
opinion that the bone superphosphate is “the best”
F
89 FERTILIZERS
is held even at the present day, notwithstanding the
equally satisfactory results that have been obtained
from the use of the superphosphates from other
sources.
Soluble Phosphoric Acid Chemically Identical,
from Whatever Source Derived
Chemically speaking, the soluble phosphoric acid
produced by the action of sulfuric acid upon mineral
phosphates is identical with the soluble phosphoric
acid derived from animal bone, and if the soluble
from each could be separated from the other sub-
stances with which they are associated; there would
be no difference whatever in the results of their use.
They are identical; just as much so as ammonia
obtained in the manufacture of bone-black from
bones is identical with the ammonia obtained in the
manufacture of illuminating gas or coke. In many
cases, doubtless, superior results have been obtained
from the use of the animal bone superphosphate,
though this has not been due to any inferiority of the
-available phosphoric acid in the mineral superphos-
phate, but rather to the fact that substances have
been compared that are not strictly comparable. They
are radically different. The one contains, in addition
to its available phosphoric acid, the only fertilizing
ingredient in the mineral superphosphate, considerable
nitrogen, and, moreover, it contains its insoluble phos-
phoriec acid in a form that is liable to decay more
rapidly than the insoluble in the mineral phosphate.
PHOSPHATES AND SUPERPHOSPHATES 83
Soluble phosphoric acid is a definite compound. The
source from which it is derived does not infiuence
this point, and the action of a definite quantity is
also identical when conditions are similar,
PHOSPHATES AND SUPERPHOSPHATES ARE NOT
IDENTICAL
The idea in the term “phosphate” should also be
kept distinct from that conveyed by the term “super-
phosphate.” The first means, and should be appled
to, any material containing as its chief constituent
phosphoric acid; the other means, and should be ap-
plied to, any material containing soluble phosphoric
acid as its chief constituent. The phosphates which
have already been described are each capable of being
converted into a superphosphate, as animal bone super-
phosphate, South Carolina rock superphosphate, bone-
black superphosphate, bone-ash superphosphate, Florida
rock superphosphate, and Tennessee rock superphos-
phate. These superphosphates vary in their content
of soluble phosphoric acid, due both to the variation
in the content of the phosphoric acid in the phosphates
used aS raw materials, and to the excellence of the
method of manufacture. In other words, the super-
phosphates, while practically identical in so far as the
form of phosphoric acid is concerned, vary in their
total content of soluble phosphoric acid. For ex-
ample, superphosphates made from the animal phos-
phates, as bone-black, bone-ash, etce., are usually
richer in soluble phosphoric acid than those made
84 FERTILIZERS
from animal bone, or from many of the mineral
phosphates, because these phosphates are of such a
character as to enable the manufacturer to convert all
the phosphoric acid present into a soluble form, and
at the same time to secure a fine, dry product, that
may be readily handled—an important consideration
in making superphosphates. .
‘Mineral phosphates, both because of their hard-
ness and of the presence of other minerals, which are
attacked by the acid, are less easily dissolved, and
require more acid in proportion to the phosphate
present than those from organic sources. They are
also less absorbent, preventing the acid from perme-
ating the mass of the material, and hence it is more
difficult to secure good condition when sufficient acid
is used to dissolve the phosphate. In making super-
phosphates from these materials, less acid is used than
is required to completely dissolve the phosphates, and
there is, therefore, always present in them more or
less of the insoluble phosphoric acid.
“In the case of animal bone, too, less sulfuric acid
is used than is required to completely dissolve the
phosphorie acid. Otherwise, a gummy, sticky product
would result, due largely to the organic matter in the
bone. The insoluble phosphoric acid in bone, bone-
black, and bone-ash superphosphates is, however, of
greater value than the insoluble in the mineral phos-
phates, for reasons already given.
“In superphosphates, too, there is nearly always
present a greater or less amount—depending upon the
material—of the second form of phosphoric acid, the
PHOSPHATES AND SUPERPHOSPHATES 85
dicaleic, reverted or retrograde. This form usually
exists in the greatest amounts in those made from
mineral phosphates, which is believed to be due either
to the soluble acting upon the insoluble portions, or
to the presence of oxide of iron and alumina, which
combine with a portion of the soluble phosphoric acid.
The soluble goes back to the less soluble dicalcic
form.””*
Aikman states the matter very clearly in the fol-
lowing words:t ‘A change which is apt to take place
in superphosphate after its manufacture is what is
known as ‘reversion of the soluble phosphate.’ Thus
it is found that on keeping superphosphate for a
long time the percentage of soluble phosphate becomes
less than it was at first. The rate at which this
deterioration of the superphosphate goes on varies in
different samples. In a well-made article, it is prac-
tically inappreciable, whereas in some superphosphates,
made from unsuitable materials, it may form a con-
siderable percentage. The causes of this reversion
are two-fold. For one thing, the presence of unde-
composed phosphate of lime may eause it. This
source of reversion, however, is very much less im-
portant than the other, which is the presence of iron
and alumina in the raw material. When a soluble
phosphate reverts, what takes place is the conversion
of the monoealcic phosphate into the dicalcic.
“Where reversion is due to the presence of iron and
** First Principles of Agriculture.” Silver, Burdett & Co., Boston.
+ Manures and Manuring.” An excellent English work, of recent issue.
86 FERTILIZERS
alumina in the raw material, the nature of the reac-
tion is not well understood, and is, consequently, not
so easily demonstrated as in the former case. Where
iron is present in the form of pyrites, or ferrous
silicate, it does not seem to cause reversion. It is
only when it is present in the form of oxide (and in
most raw phosphatic materials it is generally in this
form) that it causes reversion in the phosphate.”
Aikman also discusses the value of reverted phos-
phates, showing the estimation in which they are
held in England: “The value of reverted phosphate
is a subject which has given rise to much dispute
among chemists. That it has a higher value than the
ordinary insoluble phosphate is now admitted, but in
this country, in the manure trade, this is not as yet
recognized. At first it was thought that it was im-
possible to estimate its quantity by chemical analysis.
This difficulty, however, has been overcome, and it is
generally admitted that the ammonium citrate process
furnishes an accurate means of determining its amount.
Both on the continent and in the United States
reverted phosphate is recognized as possessing a
monetary value in excess of that possessed by the
ordinary insoluble phosphates. The result is, that
raw mineral phosphates containing iron and alumina
to any appreciable extent are not used in this country,
although they do find a limited application in America
and on the continent.”
As stated by Aikman, the reverted phosphoric acid
due to the presence of undecomposed phosphate, as
well as the reverted due to the presence of iron and
DOUBLE SUPERPHOSPHATES 87
alumina, are recognized by the chemists in this coun-
try, and this recognition is strongly encouraged by
commercial interests, because of the fact that our
mineral phosphates contain, as a rule, iron and
alumina, which by their action reduce the percentage
of the soluble. The method of chemical analysis
which has been adopted by the American Association
of Official Agricultural Chemists recognizes this form,
and it is, therefore, determined and included in the
“total available” in statements of analysis. In one
state, New Jersey, the law requires that the dicalcic
form only shall be recognized, and it assumes that the
agricultural value of this form is equal to that of the
soluble.
DOUBLE SUPERPHOSPHATES
In addition to the superphosphates made directly
from the various materials mentioned, a special sub-
stance, called a “double superphosphate,” which may
be made by dissolving low-grade phosphates with an
excess of dilute sulfuric acid, or those too poor in
phosphoric acid to make a high-grade superphosphate.
The dissolved phosphoric acid thus obtained, together
with the excess of sulfuric acid, are separated from
the insoluble materials by filtering, which acids, after
concentration, are then used for dissolving the better
phosphates ; and because the acids used for dissolving
the phosphates contain phosphoric acid, the content
of available phosphoric acid in these products is
more than double that contained in the ordinary
88 FERTILIZERS
products. These are mostly manufactured in Europe,
and are not used to any extent in this country. They
possess the advantage of containing a minimum of
impurities and a maximum of phosphoric acid in a
soluble form.
In stating the composition of superphosphates, the
three forms of phosphoric acid are all recognized.
The sum of the soluble and reverted forms is called
the “total available,” because these, as already stated,
are regarded as immediately useful to the plant. In
commercial transactions in mineral superphosphates,
the total available only is regarded,—the content of
insoluble being ignored.
CHEMICAL COMPOSITION OF SUPERPHOSPHATES
As already stated, the composition of the super-
phosphates varies according to the richness in phos-
phorie acid of the phosphates used, and according
to the character of the material. Bone-ash and bone-
black superphosphates are more uniform in composi-
tion than those derived from the mineral phosphates,
- and the phosphorie acid is practically all in the solu-
ble form. They contain on the average about 16 per ~
cent of total available phosphoric acid. The mineral
or rock superphosphates differ from these in being
more variable in their total content of available, and
in showing wider variations in the proportions of
reverted, the latter depending upon the skill in manu-
facture, as well as the character of the original
material. Well made South Carolina rock superphos-
COMPOSITION OF SUPERPHOSPHATES 89
phates contain from 12 to 14 per cent of total availa-
ble, of which 1 to 3 per cent is dicaleic, or reverted.
There are several grades of the Florida rock super-
phosphates, due to the variation in the composition of
the various raw phosphates. The pebble superphos-
phates are the richest, often containing as high as 16
or 17 per cent of total available, with varying percent-
ages of reverted and insoluble. The Tennessee super-
phosphates also vary from the same cause, the richest
showing as high as 16 to 18 per cent of total availa-
ble. The concentrated, or double superphosphates, may
contain as high as 45 per cent of available, practically
all of which is soluble. The superphosphates made
from animal bone are usually more variable in their
composition than those made from bone-black, bone-
ash or mineral phosphates, and the variation is due
both to the variability of the raw materials and the
difficulties involved in their change into superphos-
phates. The usual guarantee on an animal bone
superphosphate is 12 per cent available, and from 3 to
5 per cent of insoluble. These superphosphates also
differ from the mineral superphosphates in containing
nitrogen in addition to their phosphoric acid. They
are, therefore, really ammoniated superphosphates.
Well Made Superphosphates Contain no Free Acid
In the earlier history of the use of acid phosphates,
or rock superphosphates, objections were urged against
them, and are to some extent at the present time,
because of the supposed deleterious effects of the
90 FERTILIZERS
acids contained in them, and these objections were
undoubtedly encouraged,—certainly not discouraged,—
by those manufacturers who used only genuine bone
superphosphates. While the objections on this ground
may have had some basis in earlier times, before their
manufacture was well understood, there can be no
rational objection to their use at the present time,
when they are properly made; for while in fresh super-
phosphates a portion of the phosphoric acid may be in
the form of “free” phosphoric acid, this form in ordi-
nary superphosphates is practically all combined with
lime or other minerals before it is placed upon the
market, and there is really no more “free” acid in
the rock superphosphate than in any other. It is quite
likely this erroneous impression arose from the fact
that strong sulfuric acid was used in the manufacture,
and the belief existed that it remained as such. No
free sulfuric acid exists in well made superphosphates.
The sulfuric acid is combined with the lime to form
eypsum, as already described, and the free phosphoric
acid combines with the lime to form either a soluble
or a reverted form.
Phosphoric Acid Remains in the Soil Until Taken
Out by Plants
The phosphoric acid in superphosphates, though
soluble in water, is not readily washed from the soil.
The real object of making it soluble is to enable its
better distribution. If it were possible to as cheaply
prepare the dicalcic or reverted form as the soluble, it
THE FIXATION OF PHOSPHORIC ACID O91
would, perhaps, be quite as useful from the standpoint
of availability. After the soluble is distributed in the
soil, it is fixed there by combining with the lime and
other minerals present. It is believed that it assumes,
first, by the larger relative proportion of lime usually
present in soils, the dicalecic form, though it is not
positively certain that in the presence of an abundance
of lime, or that in time, it may not assume the in-
soluble tricaleic form. The soluble phosphoric acid
may also combine with the iron and alumina in the
soil, and form phosphates of these elements, though
recent investigations lead to the conclusion that these
conditions are much more rare than was at one time
supposed. The time required for the fixing of the
phosphoric acid, as well as the form it may eventually
assume, depends chiefly upon the character and com-
position of the soil. In those rich in lime, the fixa-
tion is most rapid, though in no sense is the fixation
immediate, and in such soils the fixation is probably
largely completed in the course of a week. On clay
soils, containing a low percentage of lime, and in
light soils that contain little clay or organic matter,
the fixation is much slower, though even in these the
chances are that no serious loss of phosphoric acid
occurs. Seldom do we find more than traces of phos-
phoric acid in drainage waters, even when heavy
applications of soluble phosphoric acid are followed
by heavy rains. The fact that the fixing power of
soils practically prevents the loss of phosphoric acid
should, however, not be used as an argument in favor
of the careless use of superphosphates.
92 FERTILIZERS
POTASH SALTS
Until the discovery of the mines of crude potash
salts in Stassfurt, Germany, in 1859, and which have
been worked since 1862, the chief source of potash
for farm plants, other than that contained in yard
manures, was wood ashes. The supply from this
source now, however, is sufficient to meet all imme-
diate as well as future demands, since the deposits
are practically inexhaustible, though notwithstanding
the abundance of the supply and the improvements
made in the methods of utilizing the various salts,
other than potash, contained in the deposits, it is the
only fertilizer constituent which has remained prac-
tically constant in price during the past fifteen years.
In this period not only have wide fluctuations occurred
in prices of nitrogen and phosphoric acid from the
different sources, but they are much lower now than
formerly.
The Importance of Potash as a Constituent of
Fertilizers
It has been attested that potash is of relatively less
importance than either nitrogen or phosphoric acid,
inasmuch as good soils are naturally richer in this
element, and because a less amount is removed in
general farming than of either nitrogen or phosphoric
acid, as the potash is located to a less extent in the
grain than in the straw, which is retained upon the
farm. It is, however, a very necessary constituent of
FORMS OF POTASH 93
fertilizers, being absolutely essential for those intended
for light, sandy soils and for peaty meadow lands, as
well as for certain potash-consuming crops, as potatoes,
tobacco and roots, since these soils are very deficient
in this element, and the plants mentioned require it in
larger proportion than do others. In fact, it is be-
lieved by many careful observers,—and the belief has
been substantiated in large part by experiments already
conducted,—that the average commercial fertilizer does
not contain a sufficient amount of this element. It is
a particularly useful constituent element in the building
up of worn-out soils, because contributing materially
to the growth of the nitrogen-gathering legumes, an
important crop for this particular purpose.
Forms of Potash
Potash, as has already been stated in the discussion
of phosphoric acid and nitrogen, exists in various
forms, but it differs from the other elements in that
its chemical form or combination seems to exert but
relatively little influence upon the availability of the
constituent. For example, it may be in the form of
a muriate or chlorid, of a sulfate or of a carbonate,
and while there is a difference in the diffusibility of
these different compounds,—that is, a difference in the
rate at which they will distribute in the soil before
becoming fixed,—there seems to be very little dif-
ference in the rate of the absorption of the potash
by the plant. Nevertheless, the form of potash must
be observed, because of the possible influence that the
O4 FERTILIZERS
substanees with which it combines may exert in
reducing the marketable quality of the crop to which
it is applied. This influence has been very distinctly
observed, particularly in the growing of tobacco, sugar-
beets and potatoes, and it has been shown that the
potash in the form of a chlorid (or muriate) does exert
a very deleterious effect, especially on tobacco. In fact,
tobacco manures should not contain potash in the.
form of a muriate. For such crops as the various
clovers, Indian corn (maize), and the various grasses, no
particular difference has been observed, and the form
of potash that may be procured at the lowest price
per pound of the constituent is the one, other things
being equal, to use for these crops.
Kainit
In the next place, the potash salts that may be
obtained are divided into two classes; first, the crude
products of the mines, and second, the manufactured
products. Of the erude products, kainit is the one
more largely used in this country than any other.
The potash contained in it is practically all in the
form of a sulfate, though its effect is the same as if
it were in the form of a muriate, because of the large
quantities of other salts, chiefly sodium chlorid, or
ordinary salt, and magnesium chlorid, with which the
sulfate of potash is associated. It contains on the
average 12.5 per cent of actual potash, or equivalent
to about 23 per cent of sulfate of potash and 33 per
eent of ordinary salt, and smaller percentages of
CRUDE POTASH SALTS 95
magnesium chlorid and magnesium sulfate. Because
of its low content of potash as compared with the
manufactured products, the cost of the actual potash
is usually greater than in these, owing to the in-
creased cost of shipping and handling per unit of
potash. It is more generally used near the sources
of supply, rather than at a distance, unless the sub-
stances, as ordinary salt, also exert a beneficial indirect
influence upon the soil, as is very frequently the
ease. It is not advisable to apply it immediately
preceding the planting, nor in the hill or row, because
of the danger to the young plant from the excess of
both the chlorids of sodium and magnesium, which
are injurious to the tender rootlets. Where its use is
intended to benefit the immediate crop, it should be
applied a considerable time before the crop is planted,
in order that it may be well distributed, and that a
portion of the chlorids, which are extremely soluble,
may be washed into the lower layers, or into the
drains.
Sylvinit
Sylvinit is somewhat similar to kainit in composi-
tion, in that it does not contain a large amount of
actual potash, and the potash is associated with other
substances, as sodium and magnesium echlorids, though
less than is the case with kainit. The potash in the
sylvinit, however, exists both in the form of a sulfate
and of a chlorid. It is not as largely exported to
this country as the kainit, and contains on the average
96 FERTILIZERS
about 16 per cent of actual potash. Its effect as an
indirect manure is very similar to that of kainit,
the salts associated with the potash having a beneficent
effect in dissolving and making other substances in
the soil available to the plant, particularly phosphates,
as well as aiding in the improvement of the physical
character of soils.
Muriate of Potash
Of the manufactured products, the muriate (chlorid)
of potash is more generally used than any of the
others. It varies somewhat in composition, accord-
ing to the method of manufacture, though prac-
tically only three grades are offered. That most
commonly met with in this country contains about
50 per cent of actual potash, equivalent to 80 per
cent muriate. The chief impurities are common salt,
or sodium ehlorid, and insoluble matter, which are not
deleterious substances. The lower the content of
potash the higher the content of impurities, though
in all cases this form of potash is sold upon the basis
of 80 per cent muriate.
Recently a Scotch kiln-dried muriate of potash has
been. offered, which is much richer in actual potash
than the other grades, containing over 98 per cent of
pure muriate. The chief advantage of this higher
grade is that the cost of handling per unit of actual
potash is reduced, a point of considerable importance
at points distant from sources of supply. The actual
potash is no better than in the lower grades. ‘
HIGH-GRADE POTASH SALTS Q7
High-grade Sulfate of Potash
High-grade sulfate of potash is usually sold on a
purity basis of 98 per cent, or an equivalent of 53 per
eent actual potash. It naturally varies somewhat in
its composition, owing to possible impurities, either
introduced or imperfectly removed. It is, however,
regarded as preferable to the muriate for some crops,
for the reasons already given (page 94), though until
recent years it has been much more expensive, and
thus not so largely used by the manufacturers of
fertilizers. It is rather less diffusible than the muri-
ate, though it is not believed to be inferior to it as a
source of actual potash.
Double Sulfate of Potash and Magnesia
This is a lower grade in its content of potash,
though similar to the high grade in its effect, as it
contains no deleterious substances, and in many eases
the sulfate of magnesia with which it is associated is
believed to be of considerable service. The potash
contained in it is equivalent to about 26 per cent of
actual potash, though lower grades are made. These
are known under the name of double-manure salts.
The cost of the actual potash in the double sulfate is
also greater than in the muriate.
Upon standing, all of the potash salts have a ten-
deney to become hard, though, with the exception of
kainit, they are easily pulverized, and thus readily
distributed, either broadeast or in drills.
G
98 FERVILIZERS
Fixation of Potash
Potash, like phosphoric acid, is readily fixed in the
soil, though the chlorids with which it is combined
when applied may form soluble compounds that are
readily leached from the soil. For example, the
chlorin combined with the muriate may be combined
with lime or soda, forming soluble chlorids of lime or
soda; hence, heavy applications of muriate of potash
may result in the exhaustion of lime in the soil. The
fact that the potash is fixed, and that the chlorids
remain soluble, enables. the application of a large
quantity, which might otherwise be injurious. That
is, if muriate of potash is applied a considerable
time before the crop that may be injured by excess
of chlorids is planted, the chlorids are washed out,
while the potash remains.
Another point of importance should be observed in
this connection: the rapidity of fixation on many soils,
especially those of an alluvial character, which ex
plains the recommendations frequently made to apply
potash salts broadcast and immediately cultivate in,
otherwise the fixation would take place at points of
contact, and the distribution be incomplete.
CHAPTER VI
MISCELLANEOUS FERTILIZING MATERIALS
In addition to the specific fertilizer materials de-
scribed in the previous chapters, which constitute the
standard sources of supply, a number of other pro-
ducts exist, and should be considered here. Certain
of these may serve in the manufacture of fertilizers,
and certain others, which are not suitable for this pur-
pose, may be used to advantage either because they
furnish the constituents in considerable quantities, or
in other ways assist in improving the fertility of the
soil. They are often a cheap source of nitrogen,
phosphoric acid or potash, besides contributing toward
“eondition” of soil, which exercises a decided infiu-
ence in making possible the best use of commercial
fertilizers.
Furthermore, while a consideration of these products
may not be regarded as strictly pertaining to the sub-
ject of commercial fertilizers, a discussion of them is
valuable, in order that certain impressions now existing
concerning them may be corrected. These impressions,
while not entirely erroneous, are not wholly in accord
with scientific facts, particularly as to how far they
may substitute the better products; and on this point
information as full and exact should be had as. the
limited knowledge that we have of the subject will
(99)
100 FERTILIZERS
permit. These various products cannot be strictly
classified into the three main groups: nitrogenous,
phosphatic and potassic. They are, as a rule, rather
general in their effect; they contain small amounts
of all the essential constituents rather than large
amounts of one or two, and many of them are useful,
practically altogether because of their indirect action.
TOBACCO STEMS AND STALKS
Tobacco stems consist of the waste stems or ribs
of the leaves, and parts of the leaves themselves,
which result from the stripping of tobacco for the
manufacture of cigars, or for smoking and chewing
tobacco. The stalks include the main stem and
branches of the plant. The stems are frequently
ground and sold as a fertilizer, and the product is
chiefly valuable for its nitrogen and potash — the
nitrogen ranging in content from 2 to 3 per cent
and the potash from 6 to 10 per cent. They contain
but small amounts of phosphoric acid. The nitrogen
exists in both the nitrate and organic forms. The
nitrate form constitutes from one-third to one-
half of the total nitrogen, and its presence is due
both to the fact that nitrogen exists as such in the
tobacco plant, and to the fact that saltpetre (nitrate
of potash) is frequently added in order to improve
the marketable quality of the lower grades of
—_— —
NOTE.— Full discussions of stable manures are contained in Roberts’
“Fertility of the Land;” and that book also has a table of compositions
of very many materials which are used for fertilizing the land.
TOBACCO STEMS 101
tobacco. The potash oceurs largely in the soluble
form, and is free from chlorids. The tobacco stalks
are somewhat richer in nitrogen than the stems,
ranging from 3 to 4 per cent, and are poorer in pot-
ash—about 4 to 5 per cent of potash—though the
forms of these two constituents are similar in the
ease of both to those contained in the stems. Both
stems and stalks may be frequently obtained in the
vicinity of towns where tobacco manufacture is carried
on, and while more variable in their content of nitro-
gen and potash than the ground stems and stalks,
due largely to the variations in the content of mois-
ture, they are a useful and often a very cheap source
of nitrogen and potash.
_ These waste tobacco products are free from dele-
terious compounds, and for this reason alone are
highly valued as a fertilizer for tobacco, as well as
for small fruits, for which they are especially useful,
because of their known insecticidal value. <A ton of
tobacco stems of good quality contains nitrogen equiv-
alent to the amount contained in 500 pounds of ni-
trate of soda, and potash equivalent to the amount
contained in 200 pounds of high-grade sulfate of
potash. They, therefore, possess a distinct value as
a source of these constituents.
CRUDE FISH SCRAP
It frequently happens that farmers are so situated
as to be able to procure directly from the fishermen
the fish scrap from which dried ground fish is made.
102 FERTILIZERS
Very large amounts are used in this crude form in
our coast states, particularly New England and the
middle states. This material, while chiefly valuable
for its nitrogen, is not uniform in its content of fer-
tilizing constituents, owing to the wide variation in
the content of moisture, or water, which may range
from as low as 25 to as high as 75 per cent. The
nitrogen, of course, varies with the dry matter, and
ranges from 2.5 to 8 per cent. The scrap also con-
tains considerable amounts of phosphoric acid, ranging
from 2 to 6 per cent. The fish scrap in this form,
too, is less valuable as a source of nitrogen than the
dried ground material, because of its coarser condi-
tion, requiring a longer time for decay.
The whole fishes (menhaden) are also used either
directly or in a composted form in many instances,
and the excellent results obtained are mainly due to
the rapidity of decay of the nitrogenous substances.
The economical purchase of these products depends
largely upon the judgment of the farmer. He should
be guided in determining their value by the amount
of water contained in them. As they approach dry-
ness, they become richer in the constituents of fer-
tility. In any case, products of this sort should be
obtained at so low a price per ton as to guarantee to
the purchaser a maximum quantity of the fertilizing
constituents for his money, when measured by the
market value of the materials of known composition.
For example, if crude fish serap, which contains
as a minimum 2.5 per cent of nitrogen, can be pur-
chased for $5 per ton, it will furnish nitrogen at 10
WOOL AND HAIR WASTE 103
eents per pound, or at two-thirds the cost of this
element in nitrate of soda at $48 per ton. Besides,
the scrap contains phosphoric acid in good forms. At
this price, the purchaser could afford to take the risk
incident to the variability of the product.
WOOL AND HAIR WASTE
Wool and hair waste have already been described
in part, though more largely from the manufacturers’
standpoint, as representing materials that may be
utilized in the manufacture of commercial fertilizers.
These products may frequently be obtained in large
quantities and at a low price per ton in towns in which
the original products are used in manufacturing, and
thus occur as wastes. Both are extremely variable in
their composition, the wool, particularly, being very
hable to change in this respect, owing both to the
admixture of non-nitrogenous substances, such as
cotton, and to the source of the waste itself,
whether it consists of the clippings and tags from the
original fleece, or whether it is in part the manu-
factured product. Different samples show a wide range
in the content of nitrogen and potash, from 2 to 10
per cent in the former, and from 1 to 3 per cent in
the latter. The nitrogen in the waste is extremely
slow in its action in the soil, though it may be made
directly useful, both as an absorbent of other wastes,
as in liquid manure, and as an ingredient of com-
posts. Excessive quantities must be applied in order
to obtain a marked immediate result.
104 FERTILIZERS
The hair waste is also variable, both on account of
the content of moisture, as well as the admixture with
it of other substances.
Lime often occurs as a waste product in some
industries, and as such it is frequently wet and pasty,
and not easily handled.
These wastes, when they can be purchased at a low
price per ton,—and frequently they may be obtained
as low as two or three dollars,—serve an excellent
purpose as absobrents, and for use in orchards and
pastures, or in gradually building up the fertility of
poor soils.
POULTRY AND PIGEON MANURES
These products accumulate in considerable amounts
on many farms, and are often more highly valued
than their composition warrants. Many believe that
they can be favorably compared with high-grade com-
mercial fertilizers. The good results obtained are
doubtless due to the readily available form in which
the nitrogen exists, since the examination of these
products does not show them to be particularly rich
in nitrogen, or in the mineral elements of fertility,
phosphorie acid and potash.
Chicken manure in the fresh state contains from
00 to 60 per cent of water, from 1 to 1.5 per cent of
nitrogen, and about .50 to .75 each of phosphoric acid
and potash. When brought to the air-dry state,—that
is, if allowed to thoroughly dry in the air,—it contains
from 10 to 20 per cent of water, and the content of
SEWAGE 105
the fertilizing constituents is about doubled. Thus,
even in the best condition, these products compare
favorably with commercial fertilizers only in their
content of nitrogen. Naturally they also vary in
their composition, according to the character of food
used in their production.
Pigeon manure differs but little from hen manure
in composition, though usually it is much drier and
somewhat richer in nitrogen.
These products should be cared for, since the con-
stituents in them serve quite as well in the feeding
of plants as those contained in the more concentrated
‘forms, though a higher estimation should not be placed
upon the constituents than upon those contained in
commercial forms which are quite as good.
SEWAGE
In recent years, great progress has been made in
the handling of sewage from cities, and there is now
a product ealled “sewage sludge,” which is obtained
in many towns, as a result of its chemical treatment.
Such examinations as have been made of this product
show it to be very poor in the fertilizing constituents,
showing less than .20 per cent nitrogen, .05 phosphorie
acid, and .05 potash. It is seldom worth the handling.
The untreated sewage and garbage wastes are also
obtainable in large quantities, and while the con-
stituents contained in them act quickly, and while
they are considerably richer in these than the sludge
wastes, it seldom pays the farmer to handle them,
106 FERTILIZERS
owing to their offensive character and the enormous —
amount of useless moisture contained in them.
MUCK AND PEAT
“On many farms there are low, wet places, where
the conditions are favorable for the collection of
partially decayed vegetable matter. The material thus
formed is called muck or peat. The thickness of the
deposit, and its character, depend upon the time during
which it has been formed, and the character of the
climate.” *
Muck is used mainly as a source of humus, and
serves an excellent purpose as an absorbent in
eattle stalls or yards. Fresh muck, while varying in
composition according to its source, may be said to
contain on the average 75 per cent of water and
about .75 per cent of nitrogen, and only traces of
potash, phosphoric acid and lime. Air-dry muck also
varies 1n composition, largely owing to the different
proportions of vegetable and mineral matter contained
in the different products, as well as the amount of
water absorbed in its dry state. The richer it is in
vegetable dry matter, the richer in nitrogen. The
value of the muck as a source of humus is measured
by its content of nitrogen, while its value as an ab-
sorbent depends upon its content of organic matter.
The value of muck for either of these purposes is
further modified by the labor necessary to secure it in
* Voorhees, “First Principles of Agriculture.”
KING CRAB—MUSSELS 107
a dried condition. This product is of doubtful value
as a source of immediately available nitrogen.
“The usual method of securing it is to throw it
out of the bed into heaps, and allow it to dry before
it is used, either upon the field or in the stables.
Where a muck bed exists upon a farm, it should first
be studied in reference to its possible drainage. If it
can be drained, it is liable to prove more useful where
it lies than for the other purposes mentioned.” *
KING CRAB, MUSSELS AND LOBSTER SHELLS
King crab, already described in the discussion of
nitrogenous fertilizing materials (page 43), is also
used in many sections of New Jersey in its green or
fresh state, either directly on the land or in the form
of a compost, and because of its nitrogenous charac-
ter, and its tendency to rapid decay, is a valuable
source of this element, of which, in its fresh state, it
contains from 2 to 2.5 per cent.
In certain sections of the coast states farmers have
access to an almost unlimited supply of mussels, which
may be had for the carting. Analyses made at the
New Jersey Experiment Station show them to contain,
in their natural state, a very considerable amount of
fertilizing constituents, the nitrogen reaching .90 per
cent, the phosphoric acid and potash .12 and .13 per
cent, respectively, and the lime 15.84 per cent.
The organic portions of the mussels decay rapidly,
** First Principles of Agriculture.”
108 FERTILIZERS
and serve as a fairly good source of nitrogen; and
since this product is twice as rich in this constituent
as average yard manure, it is well worth the expense
of handling.
Lobster shells are also a waste of considerable im-
portance, since they can be obtained at a very low cost,
often for the carting. They contain, in their dry state,
an average of over 4 per cent of nitrogen, 3 per cent
of phosphoric acid, and about 20 per cent of lime.
These products, of course, are not to be depended
upon for the entire supply of constituents to crops;
they are mainly useful in improving the natural quality
of the soil by building it up in vegetable matter con-
taining nitrogen. Their best use requires the addition
of the minerals from other sources.
SEAWEED
In the coast states, seaweed is held in high esteem
as a manurial product. In Connecticut, Rhode Island
and New Jersey, the use of seaweed as a fertilizer is
very general. In Rhode Island the annual value of the
manure from this source has been estimated to be as
high as $65,000.*
In its fresh state it contains from 70 to over 80 per
cent of water, and is thus economically used in that
condition only near the shore. It is frequently spread
out in thin layers and dried, in which condition it can
be profitably transported considerable distances.
* Bulletin 21, Rhode Island Experiment Station.
WOOD ASHES 109
Seaweeds of different kinds differ in their content
of the fertilizing constituents. Certain of them show
a relatively high content of nitrogen, and others of
potash, and they furnish more of these constituents
than of phosphoric acid. All seaweeds contain con-
siderable salt, though if they are not used in too large
quantities, no serious injury is liable to follow. In
fact, salt in some instances is a substance of con-
siderable indirect manurial value. Seaweed manure
is certainly worthy of consideration where it can be
obtained in quantity for the expense of carting.
WOOD ASHES AND TAN-BARK ASHES
_ Wood ashes contain potash in one of the best forms,
and were, in the early history of manuring, practi-
eally the only semi-artificial source of this element.
At the present time, however, the supply is limited,
and the average content of potash in the commercial
article is much lower than was formerly the case.
The pure ash is not a uniform product. That from
the different varieties of wood varies in composition.
As a rule, the softer woods are poorer and the hard
woods richer in potash than the average, the range
being from 16 to 40 per cent.
“Ashes also contain lime in large quantities, while:
phosphoric acid is contained in much smaller quanti-
ties. Wood ashes, as usually gathered for market,
however, contain very considerable proportions of mois-
ture, dirt, etc., which cause a variability in composition
not due to the character of the woods from which they
110 FERTILIZERS
are derived. The average analysis of commercial wood
ashes shows them to contain less than 6 per cent of
potash, 2 of phosphoric acid and 382 per cent of lime.
Leached wood ashes contain on the average 30 per cent
of moisture, 1.10 of potash, 1.50 of phosphorie acid
and 29 per cent of lime.
“Ashes are probably one of the best sources of
potash that we have, so far as its form and combina-
tion are concerned, being in a very fine state of divi-
sion, and in such a form as to be immediately available
to plants. Ashes also have a very favorable physical
effect upon soils, the lime present, of course, aiding in
this respect. Canada is now the main source of wood
ashes, the substitution of coal for wood making the
supply in this country for commercial purposes very
limited. Owing to the variability of this product, it
should always be bought subject to analysis, and to a
definite price per pound for the actual constituents
contained in it, which should not be greater than the
price at which the same constituents could be pur-
chased in other quickly available forms.” *
Tan-bark ashes are much poorer in fertilizing
content than those obtained from the regular com-
mercial sources of supply. They seldom contain more
than 2 per cent of potash, 1.5 per cent of phosphoric
acid and 33 per cent of lime.
Lime-kiln ashes are obtained in the burning of
lime with wood, and are also relatively poor in potash,
containing less than 1.5 per cent of potash and 1 per
* Hirst Principles of Agriculture.”
COAL AND COTTON-HULL ASHES her
eent of phosphoric acid. The product is, however,
much richer in lime than the average wood ashes, often
eontaining as high as 50 per cent of calcium oxide.
COAL ASHES
It is believed by many that coal ashes, because of
their favorable effect upon many soils, also possess
considerable fertilizing value, whereas analyses. show
them to contain only traces of soluble potash and of
phosphoric acid. The good results from their use is
undoubtedly due to their beneficial indirect effect in
improving the physical character of heavy soils.
COTTON-HULL ASHES
Cotton-hull ashes were formerly made in consid-
erable quantities in the southern states, where the
hulls were used as fuel in the furnaces connected with
gins and presses. This product, while exceedingly
variable in composition, is usually very rich in potash,
besides containing a very considerable amount of
available phosphoric acid. A large number of samples
have been examined at the Connecticut Experiment
Station,“ and the results of the study show that no
average percentage composition is a sufficient guide
as to their quality. They can be safely purchased
only on the basis of their actual composition. They
are an excellent source of potash and phosphoric acid,
*Annual Report for 1897 (Part 17.2 Connecticut Experiment Station.
419 FERTILIZERS
because free from chlorids and other deleterious sub-
stances, but are not so rich in lime. They are espe-
cially useful for such crops as are injured by the
presence of chlorids.
MARL*
Marl may contain one or more of the constituents,
phosphoric acid, potash and lime. Shell marls are
usually very rich in lime, but contain only traces of
phosphoric acid and potash. The green sand marls of
New Jersey often contain very considerable amounts
of phosphoric acid and potash, though they vary
widely in composition. They contain, on the average,
2.20 per cent of phosphoric acid, 4.70 per cent of
potash, and 2.90 per cent of lime. These constituents,
particularly the potash, are, as a rule, slowly available.
Marl, however, is an important amendment to soils,
not only because of its content of mineral constituents,
but because these constituents are associated with
products that exert a very favorable mechanical effect
upon soils. Large areas of land in the state of New
Jersey, formerly unproductive, chiefly because of phy-
sical imperfections, have been made very productive
mainly through the application of marl.
The use of marl is now less general than when the
fertilizing constituents from artificial sources were
dearer, and when the labor of the farm was more
abundant and cheaper. The quicker effect of more
soluble fertilizer constituents has had an influence in
**Pirst Principles of Agriculture.”
LIME 413
reducing the use of marl where quick returns are
desirable. Where farmers have deposits of marl upon
their own farms, or within short distances of them,
and can secure it at a low price per ton, its ap-
plication is a desirable method of improving land.
The results from the use of marl are frequently due
quite as much to the improvement given to the phy-
sical condition of soils as to the increase in fertility
furnished by the essential mineral constituents. Marl
may be carted and spread upon the land when other
work of the farm is not pressing, thus making it
possible to get a considerable addition of fertility at a
small expense.
LIME
“Lime, as it is generally known, is an oxide of
ealeium, and is produced by burning limestone, or
carbonate of lime. The lime loses the earbonie acid
when burned in the kilns, and the oxide of lime
remains behind; this is termed ‘burned lime,’ ‘quick-
lime,’ or ‘stone lime,’ and is usually slaked before
it is applied to the soil. This is done by adding
water, which the lime absorbs, and falls to a powder.
Slaked lime, also called caustic lime, is a calcium
hydrate.
“The more completely limestone is burned, the
better the quicklime, and the more completely it
slakes. We have, when we speak of lime, three
forms: limestone, quicklime and slaked lime, each dif-
fering from the other in composition.
H
114 FERTILIZERS
“Quicklime absorbs moisture, and slakes when
exposed to the atmosphere. Lime thus slaked is
called ‘air-slaked lime,’ and is usually less com-
pletely changed to a hydrate than when water is
added. Quicklime also absorbs carbonic acid from
the air, and changes back to the limestone form.
Lime in the carbonated form, if finely pulverized, is
better for liming light lands than the caustic lime,
while for heavy lands, the caustic is preferable to
the carbonate.” *
What is termed “marble lime” is made from pure
limestone, and the burned lime thus obtained is prac-
tically pure oxide of lime. Limestone, so ealled, is
not always pure. It is a mixture of lime and mag-
nesia, in which ease it is the mineral “dolomite,” and
is termed “magnesian limestone.” A very large
quantity of the lime used in the eastern states is the
magnesian form. The burned lime from the magne-
sian limestone contains from 50 to 60 per cent of
calcium oxide, and 380 per cent or over of magnesium
oxide. In some instances, the magnesia is of value,
though it is rather inert in its effect, and is less use-
ful than the lime. A safe rule in the purchase and
use of lime is to adjust the price to the proportionate
percentage of actual lime present, or practically in
the ratio of 10 to 7.
Oyster shells are nearly pure carbonate of lime,
and oyster shell lime, while practically pure lme, so
far as this element is concerned, is usually mixed with
SS
** First Principles of Agriculture.”
GAS LIME AND GYPSUM 115
more or less dirt and other impurities, and is, there-
fore, not as rich in lime as that derived from pure
limestone.
“Gas lime is also frequently used as manure; in
gas works, quicklime is used for removing the impuri-
ties from the gas. Gas lime, therefore, varies con-
siderably in composition, and consists really of a mix-
ture of slaked lime, or calcium hydrate, and ecarbo-
nate of lime, together with sulfites and sulfides of lime.
These last are injurious to young plant life, and gas
lime should be applied long before the crop is planted,
or at least exposed to the air some time before its
application. The action of air converts the poisonous
substances in it into non-injurious products. Gas
lime contains on an average 40 per cent of calcium
oxide, and usually a small percentage of nitrogen.” *
Where it can be used to advantage, its cost should,
as in the case of the other, be based on the proportion
of actual lime present.
Gypsum is a sulfate of lime, containing water in
combination. Pure gypsum contains 32.5 per cent of
lime, 46.5 per cent of sulfuric acid, and 21 per cent
of water.
Plaster of Paris is prepared from gypsum by burn-
ing, which drives off the water it contains.
Gypsum, like other forms of lime, furnishes directly
the element calcium, and also exerts a favorable solvent
effect upon the soil. It was formerly used in large
quantities, particularly for clover, and it is believed
** First Principles of Agriculture.”
116 FERTILIZERS
that its favorable effect was due, not so much to the
direct addition of lime, as to its action upon insoluble
potash compounds in the soil, in setting free potash.
Thus the application of plaster caused an increase in
crop, because of the potash made available.
We have in the eastern states two main sources
of gypsum, namely, Nova Scotia and Cayuga, N. Y.
Nova Scotia plaster contains on the average over
90 per cent of sulfate of lime, and is, therefore,
purer than that obtained from Cayuga, which often
shows as low as 65 per cent of pure sulfate; the
latter, however, frequently contains appreciable amounts
of phosphoric acid.
In many places it is possible to obtain plaster
which is a waste in the manufacture of phosphorus.
This waste contains the plaster in a precipitated form,
and frequently also contains considerable amounts of
phosphoric acid. The disadvantage of this waste lies
in the fact that it is frequently wet and lumpy, and
thus not easily handled and distributed. Its advan-
tage lies in its content of phosphoric acid, which
ranges from 1.5 to 2 per cent, though as a rule, it can
be purchased at a lower price per ton than that from
the regular sources.
AGRICULTURAL SALT
Agricultural salt, which is chiefly common salt, is
also frequently used as a manure. “It supplies no
essential plant-food constituents, and its value is still
a disputed point, though it is admitted that where its
SALT AND POWDER WASTE TIT
use is favorable, it is due to indirect action in aiding
the decomposition of animal and vegetable matter,
increasing the absorbing power of soils, and, by its
reaction with lime, acting as a solvent for phosphates.” *
There would seem to be no good reason for paying
from $4 to $6 per ton for this substance, when prac-
tically the same effect can be obtained from the salt
contained in the crude potash salt, kainit, one-third
of the total weight of which is common salt. This,
too, may be had free of charge, or for the handling,
as the market price of the kainit is based upon its
content of potash.
POWDER WASTE
Powder waste also consists largely of common salt,
though frequently containing appreciable percentages
of nitrogen in the form of a nitrate. Its use can
only be recommended when it ean be obtained ata
low price per ton, or for the handling, and upon soils
that show a marked benefit from its application.
GREEN MANURES
A great deal of misconception is prevalent con-
cerning the value of what are termed “green manures.”
These do possess a distinct value, and a proper under-
standing of their place in farm management will
undoubtedly result in their larger and better use, and
** First Principles of Agriculture.”
118 FERTILIZERS
in the consequent improvement of agricultural prac-
tice. By green manures is meant any crop that is
grown primarily for the purpose of improving the
soil, and not for the harvested product.
“ Nitrogen Gatherers” and “ Nitrogen Consumers ”
In this sense any crop will serve as a green
manure, yet certain crops possess a greater value than
others for this purpose, because they are able to obtain
certain of their constituents from sources not acces-
sible to all crops. In other words, the one class of
plants can obtain the nitrogen necessary for their
growth from the air, as well as from the soil; the
other, as far as we now know, ean obtain it only
from the soil. These two groups of plants are, there-
fore, classified as “nitrogen gatherers” and “nitrogen
consumers.”
The nitrogen gatherers belong to the legume, or
clover family, and do not depend solely upon soil
sources, but rather gather the element from outside,
and thus do not reduce the content of soil nitrogen.
Distinguishing features of the plants of this order
are that the seeds are formed in a pod or legume, and
that they have the power of acquiring at least a large
part of their nitrogen from the air. These, when
plowed down as green manures, add directly to the
crop-producing capacity of soils poor in nitrogen,
because increasing their content of this element. In
order that the plant may obtain its nitrogen from
the air, however, the soil must originally contain, or
Sy -
=.
THE ADVANTAGES OF GREEN MANURES 119
must be inoculated with, a specific germ, the presence
of which is manifested by the growth of nodules
upon the roots, through which it is believed the
nitrogen is obtained. Most well-tilled soils contain
these germs in abundance.
The “nitrogen consumers” are those which can
obtain their nitrogen only from the soil; these con-
sume the nitrogen existing there, and their growth
and removal exhausts the soil of this element.
Notwithstanding the very great,advantages of .the
“nitrogen gatherers” as green manures, they cannot
be solely depended upon to increase the crop-produc-
ing capacity of the soil. That is, soils that are very
poor, both in their content of nitrogen and of the
essential mineral elements, cannot be made very pro-
~duetive by the sole use of green manures. In fact,
the green manure crops cannot be grown with ad-
vantage unless they are supplied with an abundance
of the mineral elements, phosphoric acid and potash ;
hence helpful green manuring for such soils must be
preceded and accompanied by liberal fertilization with
the minerals, phosphoric acid, potash and lime. With
these added in sufficient amounts, and with the specific
bacteria present in the soil, their use results not only
in the addition of nitrogen to the soil, which may be
useful: for other plants, but by the accumulation of
vegetable matter, which improves the physical char-
acter, usually imperfect in this class of soils. The
nitrogen thus introduced into the soil is also in a very
good form; that is, it has a tendency to decay rap-
idly and thus supply the needs of other plants, but
120 FERTILIZERS
the helpful additions to the soil are limited to organic
matter and nitrogen. The mineral constituents ab-
sorbed by the crop may be more available for other
crops, but they formerly existed there. No additions
of these are made by the growing of the crop; hence
no system of green manuring can be made successful
unless chere is a previous abundance in the soil of the
mineral elements, or unless these have been directly
applied.
The Most Useful Crops
Of the crops most useful for green manures, red
clover, crimson clover, cow peas and soja beans are
first in order; first, because of their capacity to
gather nitrogen, and second, because of their period
and time of growth. Whether these plants will
gather all of the nitrogen of their growth from the
air, other conditions being good, depends upon
whether the soil is rich or poor in nitrogen, since it
has been shown that these plants will gather at least
a part of the nitrogen from the soil in preference to
that from the air, unless they are starved in respect
to soil nitrogen. The amounts that may be gathered
from the air, therefore, are not measured by the total
content of nitrogen contained in the plant grown
(which may, in the case of good crops, amount to as
much as 200 pounds per acre, sufficient for the use of
several good crops of wheat, or other cereal grains),
but apparently by the poverty of the soil in this ele-
ment. The fact that an accumulation of nitrogen
does occur has been distinctly shown, and their con-
CROPS USEFUL AS GREEN MANURES 1
tinuous growth, therefore, would have a tendency to
over-enrich the soil in this constituent, unless accom-
panied by an abundant supply of minerals, particu-
larly in the improvement of light lands and in
orchards and vineyards, for which their right - use
is very beneficial.
Experiments conducted in this as well as other
countries, show that the nitrogen so gathered and
stored in the soil may be readily obtained by cereal
and other nitrogen-consuming crops. An experiments
conducted by the New Jersey Experiment Station, on
a poor, sandy soil, in which the mineral elements,
phosphoric acid, potash and lime, only, were added,
a crop of cow peas gathered, in the roots and tops,
75 pounds of nitrogen, equivalent to that contained
‘in 470 pounds of nitrate of soda, which when turned
under was capable of feeding a rye crop with suf-
ficient nitrogen to produce a most excellent crop,
quite as good as that grown on land long under eul-
tivation and well-manured. Further experiments con-
ducted with crimson clover* show that the nitrogen
gathered was capable of supplying the needs of fruit
trees quite as well as when the nitrogen was applied
in the immediately available form contained in nitrate
of soda.
If it were necessary to do so, numerous experi-
ments might be cited to show that the nitrogen is
gathered from the air by these plants, and that it is
eapable of providing that required for those other
crops which can obtain it only from the soil.
* Annual Report for 1894, New Jersey Experiment Station.
I ley FERTILIZERS
Green Manure Crops that Consume the Nitrogen
in the Sorl
In addition to the legumes, other crops are used
as green manures, chief of which are rye, buckwheat
and mustard, not because they are capable of directly
gathering nitrogen, but because their period and time
of growth are such as frequently to enable them to
serve a very useful purpose in preventing losses in
fertility. In the growth of these crops, however, the
only real addition to the soil is the amount of non-
nitrogenous organic matter contained in them. The
nitrogen gathered is in direct proportion to the
amount contained in the soil and the relative feeding
eapacity of the plant. The nitrogen is not obtained
from the atmosphere, and the soil has not accumu-
lated nitrogen by virtue of their growth, and is not
richer in this element, except in so far as by their
growth they prevent the escape of readily available
nitrogen into the drainage waters. The nitrogen
gathered is “soil nitrogen,” and its conversion into a
crop simply results in changing its form and place.
The specific use of these crops, therefore, so far as
directly contributing to the fertility of the soil is con-
cerned, is to prevent the possible loss of nitrogen and
other constituents by leaching, which is more liable
to occur on uneropped soils, though they further
contribute toward soil improvement by accumulating
stores of non-nitrogenous vegetable matter.
These crops, too, in order that they may produce
largely, must be freely supplied with the mineral ele-
THE RIGHT USE OF GREEN MANURES 123
ments, as well as with nitrogen in some form, and
cannot be regarded as a substitute for the leguminous
crops, or as a substitute for commercial fertilizers in
the permanent improvement of the soil, in the sense
that they actually contribute to its content of fertility
elements,—an opinion apparently held by many who
have observed the good results that often follow
their use.
Furthermore, these crops contain, as a rule, less
nitrogen, and besides, that contained in them is
apparently less available than the nitrogen contained
in the green manures from the leguminous crops. In
their growth, too, they appropriate the immediately
available nitrogen of the soil, and convert it into the
less available organic form; hence the crop that fol-
lows is frequently unable to obtain its food as readily
as would have been the case, provided the green
manure crop had not been grown. Therefore, while
the practice of using green manures is a desirable one
when properly understood, it should not be regarded
as a means by which soils may be directly enriched,
except in the case of the plants of the legume family,
where nitrogen is really added to the soil. In the
ease of all other crops, the benefit is indirect, and is
in proportion to the amount of minerals added.
CHAPTER VII
PURCHASE OF FERTILIZERS
COMMERCIAL fertilizers, in the form in which they
are obtained by farmers, are made up of varying pro-
portions of one or more products from each class of
fertilizing materials described. That is, every manu-
facturer is obliged to go to these sources of supply,
whatever may be the name given to the finished
product or mixture. Hence the fertilizing materials
deseribed are not regarded as commercial fertilizers in
the same light as those which they are able to pur-
chase under brand names from their local dealers. In
the first place, a specific fertilizing material, as dis-
tinct from a manufactured fertilizer, contains, as a
rule, but one of the essential fertilizing elements, and
its use under average conditions would be far differ-
ent from one which contains two or all of the essen-
tial fertilizing elements. The materials, therefore,
are classed as nitrogenous, phosphatic and potassie,
according to whether the material contains nitrogen,
phosphorie acid or potash as its chief or its only
constituent element; and these different classes, too,
may be again sub-divided into two distinct groups,
the first including “standard,” or high-grade materials,
and second, “general,” or low-grade materials. This
classification is of the utmost importance.
(124)
HIGH-GRADE FERTILIZING MATERIALS Po
STANDARD HIGH-GRADE MATERIALS
Nitrate of soda, sulfate of ammonia, and dried
blood are, for example, standard or high-grade
nitrogenous materials, and belong to the first group.
They are “standard” because they do not vary widely
in their composition. A definite quantity can be
depended upon to furnish not only practically the
same amount of the specific constituent, but to fur-
nish it in a distinet and definite form, which is iden-
tical, from whatever source derived. For example,
commercial nitrate of soda does not vary materially.
in its composition, and the nitrogen in it is always in
the form of a nitrate. The same is true of sulfate
of ammonia. One ton will furnish practically as much
nitrogen as any other ton, and it is always in the
form of ammonia. It is also practically true of high-
grade dried blood. Hach lot contains this specific form
of organic nitrogen, and will always decay at
practically the same rate, if used under the same
conditions. They are also high-grade products because
they are richer in the constituent element, nitrogen,
than any other, and because this element is im-
mediately or quickly available.
The South Carolina, Florida and Tennessee rock
phosphates differ from the nitrogenous materials men-
tioned, inasmuch as, in their raw state, they are not
directly useful as fertilizers,—they are not sources
of available phosphoric acid. Hence the standard
supplies of phosphoric acid are derived from these
materials after they are manufactured into superphos-
126 FERTILIZERS
phates. The various kinds of these may be regarded
as high-grade in the sense that they always possess
a high content of available phosphoric acid. They
are standard, too, not only because of this, but
because they do not vary widely in their composi-
tion. A definite amount from each class can be de-
pended upon to furnish practically the same amount
of available phosphoric acid. For example, a ton of
South Carolina rock superphosphate, from whatever
manufacturer obtained, will not vary widely in its
content of phosphoric acid, and will always act in
the same way under similar conditions. The various
German potash salts are also standard and high-grade,
since the composition of each grade and kind is
practically uniform in its content of potash, which
will always act in the same way under the same con-
ditions, and since they are richer in the specific ele-
ment, potash, than other potassic compounds suitable
for the manufacture of fertilizers.
These various standard, high-grade products, when
used in the manufacture of fertilizers, make what are
called “chemical fertilizers,” because they are really
crude chemical compounds, and furnish the particular
fertilizer elements in their most concentrated and
active forms.
FERTILIZING MATERIALS WHICH ARE VARIABLE IN
COMPOSITION
The products which are included in the second
eroup differ from the others, in that they not only
VARIABILITY OF LOW-GRADE MATERIALS 127
vary in their content of the specific constituent, or
in their composition, but they are also variable in the
sense that the constituents contained in them do not
show a uniform rate of availability. For example,
ground bone varies in its composition owing to its
source and the method of treatment, and the availa-
bility of the constituents, nitrogen and phosphoric
acid, also varies because of these conditions, and
because of its mechanical condition or degree of
fineness. Different samples of bone derived from the
Same source, treated in the same way, and ground
to the same degree of fineness, would be regarded as
standard, but because these conditions differ, bone
from different sources cannot be depended upon to
act in the same way under the identical climatie and
soil conditions. This is also true of tankage, which
varies, not only in the total amount of the constitu-
ents contained in it, but in the proportion of its two
chief constituents, nitrogen and phosphoric acid, and
in the rate at which they become available to plants.
In this class belong, in addition to the bone and
tankage, ground fish, and the various miscellaneous
products. They cannot be depended upon, either in
respect to their composition or their availability of
the essential constituents—important advantages pos-
sessed by the standard products.
HIGH-GRADE AND LOW-GRADE FERTILIZERS
The fertilizers manufactured from these two classes
of raw materials will, therefore, differ. Those made
128 FERTILIZERS
from the first class are always high-grade, both in
reference to the quality and quantity of the constituents
that may be contained in a mixture. Those manu-
factured from the second group are not high-grade,
so far as the form of the constituent is concerned,
though they may be high-grade in the sense that they
contain large amounts of them. In the manufacture
of fertilizers, too, as a rule, all three of the essential
constituents are introduced, and the buying of a fer-
tilizer is really the buying of the three constituents,
nitrogen, phosphoric acid and potash. Hence, the
more concentrated the product, or the richer it is in
these constituents, the less will be the actual cost of
handling per unit of the constituents desired, and the
higher the grade of the materials used, the greater
the proportionate activity of the constituents.
The “ Unit” Basis of Purchase
In commercial transactions in fertilizing materials,
two systems of purchase are used. The first is known-
as the “unit” system, in which case the quotations, or
prices are based on the unit. A unit means one
per cent on the basis of a ton, or 20 pounds. For
example, a unit of available phosphoric acid means
20 pounds, and a quotation of $1 per unit would be
equivalent to a quotation of 5 cents per pound. In
the trade, sales are always made on this basis. The
system is also applied to such nitrogenous products as
blood, meat, hoof meal, concentrated tankage, ete.
The price is fixed at so much a unit of ammonia.
*ONIT” AND “TON” BASES OF PURCHASE 129
This system is probably the most perfect, and certainly
cannot but be satisfactory to both the dealer and the
consumer. It results in the consumer receiving exactly
as much as he pays for, and the producer is paid for
exactly what he delivers. The number of units in
each material sold is fixed in each case by the chemist
to whom the samples are referred.
The “Ton” Basis of Purchase
The other method of purchase is known as the “ton
basis,” and is used almost exclusively in the sale of
other materials than the standard products mentioned,
and manufactured fertilizers. This system works well
with standard high-grade products, since the ton price
is, in this case, a fair guide as to the cost of the con-
stituents, though it cannot be as satisfactory as the
other, since even the best materials may vary suffi-
ciently to cause a difference in actual cost of the
constituents, even though the price per ton remains
‘unchanged. In this method, the products are usually
accompanied by a guarantee, the purpose of which is
to indicate the minimum amount of the constituents
contained in the material.
*.
The Necessity of a Guarantee
In the purchase of mixtures, consumers should
demand that they be accompanied by a guarantee,
because they are unable to determine the kind and
proportion of the different materials entering into
I
130 FERTILIZERS
the mixture, either by its appearance, weight or smell.
In mixing, too, an opportunity is afforded for dis-
euising poor forms of the constituents, particularly
nitrogen. That is, in a mixture of nitrogenous
materials, potash salts and superphosphates, it would
be a difficult matter to determine, by mere physical
inspection, the proportion of the nitrogen which had
been supplied in the form of horn meal and of blood,
and the statement of the manufacturer on this point
would be valuable in proportion to his reliability.
The fact that in mixtures it is impossible for the con-
sumer to distinguish or determine the proportions,
amounts or kinds of the constituents is so fully ree-
ognized that it has resulted in the enactment of laws
in most states, which require that manufacturers or
dealers in fertilizers shall state the actual amounts of
the different constituents contained in their products,
as well as the sources from which they were derived,
and which fix a penalty for any failure to comply with
the law in this respect. A chemical control is in these
eases provided for, and it has been of great service
both to the good manufacturers, because it tends. to
reduce the number of low-grade brands which would
naturally come into competition with them without
such protection, and to the consumers, because it
protects them from fraudulent products.
Laws Alone do not Fully Protect
Laws alone, however, are not sufficient to fully
protect the farmer in this respect. He must possess,
PURCHASE OF FERTILIZERS 131
in addition, a knowledge of what constitutes a good
fertilizer, and must be able to determine from the
analysis whether there is a proper relation between
the guarantee and the selling price, and whether the
materials that have been used are of good quality.
The fact that there is a very decided lack of the right
sort of intelligence on this point, is shown by the
results of the work of the different fertilizer control
stations. These demonstrate clearly that farmers do,
in many cases, pay exorbitant prices for their fer-
tilizer constituents, not because the manufacturer did
not sell what he claimed to sell, but because the
price charged by the dealer was far in excess of that
warranted by the guarantee. For example, it has
been repeatedly shown that of two farmers in the
‘same neighborhood, the one who studies the matter
and understands the relation of guarantee to selling
price, may pay 15 cents per pound for his nitrogen,
while the other, who does not study the matter, buys
on the ton basis, and does not know that there should
be such a relation between the two, may pay 30
eents per pound for the same quality of the same
constituent. This may be illustrated by the follow-
ing examples:
Two brands are offered, made up from the same
kind and quality of materials. No. 1 is guaranteed
to contain:
OE Oe a | ee Pee ne nd eae ee 1%
Euosauoric acid (available) .-.. 6)... 6s ie es 6 %
RR Ae ar a act eta EN ae RAL ge aks ain Seay 1%
132 FERTILIZERS
and sells for $20 per ton; and No. 2 is guaranteed to
contain:
PED ce a. GAS Sc, id eds as et a aS ee 4%
Phosphoric acid (available). ...... epee roe. 8%
PRM A eg te kG org ete a es ee 2%
and sells for $22 per ton. The farmer who buys on
the ton basis, or is guided only by the ton price, will
be induced to purchase the No. 1 brand, because by
so doing he apparently saves $2 per ton. The one
who studies the relation of guarantee to selling price
will purchase the No. 2 brand, because he finds, from
a simple calculation, that it furnishes the constituents
at just one-half the cost per pound of the No. 1
brand, notwithstanding the higher ton price, which
is shown by the following calculation:
No. 1
Lbs. Cts.
per ton per lb.
PUA Pht os aided is Ta 1% K 20= 20 @ 30 = $6 00
Phosphorie acid (available) 6% K 20 = 120 @ 10 = 12 00
IPGL ere aie 1% K 20 =-20 @ 10 = 20
$20 00
No. 2
Lbs. Cts.
per ton per lb.
by [iii os 51! eo ani Mes oe 4% KX 200= 80@15 = $12 00
Phosphorie acid (available)8% K 20 =160@ 5= 8 00
POE 2 be ode) a ee ee 2%. XK 20 =" 40.@ b=] sae
$22 00
In reality, the fertilizer at $22 per ton is cheaper
than the one at $20 per ton.
STATEMENT OF GUARANTEE 133
Cost per pound of constituents in:
No.1 No. 2
NEN See Pg ee Bg ae $0 30 $0 15
Phosphorie acid (available) ....... 10 05
MMMM ato ig isa od 8 oe See yes, us 10 05
This may seem an extreme case, but it is well
within the facts, which may be ascertained by con-
sulting the bulletins on fertilizer analyses, as pub-
lished by the different states.
Method of Statement of Guarantee Sometimes
Misleading
Guarantees, too, are sometimes rendered con-
fusing to the purchaser, because of the method of
their statement, though the different methods used
“are, in one sense, entirely legitimate, because the
terms used are in accordance with the facts. From
a chemical standpoint, at any rate, it is quite as
legitimate to guarantee the percentage of phosphorie
acid equivalent to bone phosphate of lime, as it is to
guarantee the percentage of actual phosphoric acid.
It is because the consumer believes that the ‘equiva-
lent” in combination means that he is obtaining some-
thing more than when actual constituents only are
euaranteed, that he is led to purchase more freely,
or to pay a higher price. Nitrogen may be properly
stated in its equivalent of ammonia, phosphoric acid
in its equivalent of bone phosphate, and potash in
its equivalent of muriate of potash, and it is the
business of the purchaser to understand the relations
of the two methods of statement, in order that he
134 FERTILIZERS
may not be misled in his purchases. The following
table shows the terms used, their equivalents, and
the factor to use in multiplying, in order to convert
the one into the other:
To convert the guarantee of Multiply by
CAC a ea oa ae Nitrogen ..... .. .»:.. Gass
urna ery FU ta vA | ATMMOBI 4.0." soe 1.214
Nitrate of soda... . Nitrogen... <a 0.1647
Bone phosphate. . . | Pra ere Phosphorie acid . . . 0.458
Phosphoric acid. . . } equivalent + Bone phosphate . . . 2.183
Muriate of potash. . | of Actual potash . . . . 0.632
Actual potash. .. . Muriate of potash . . 1.583
Sulfate of potash . . | Actual potash .. . . 0.54
Actual potash. ... J Sulfate of potash.. . 1.85
Discussion of Guarantees
It is shown in this table that, in order to convert
ammonia into its equivalent of nitrogen, the percent-
age of ammonia should be multiphed by 82 per cent,
or divided by the factor 1.214, because ammonia is
82 per cent nitrogen, and because one part of the
nitrogen is equivalent to 1.214 parts of ammonia.
In order to determine the cost per pound of nitro-
gen in dried blood, which is quoted, for example, at
$2 per “unit,”—20 pounds of ammonia,—the unit 20
pounds is multiplied by 82 per cent, which gives
16.40 as the pounds of nitrogen offered for $2, or
12.14 cents per pound.
Bone phosphate of lime is, in round numbers, 46
per cent actual phosphoric acid. Hence, by multi-
plying the bone phosphate by 46 per cent, the per
METHODS OF GUARANTEEING 135
eent of actual phosphoric acid is obtained. Ground
bone, for example, guaranteed to contain from 48 to
52 per cent bone phosphate, contains, in round num-
bers, 22 to 24 per cent of phosphoric acid. Sulfate
of potash is 54 per cent, and muriate of potash is
63 per cent “actual” or potassium oxide, respectively.
Hence, to convert the percentages of these forms
into their equivalents of “actual,” they are multiplied
by the factors given.
In such raw materials as nitrate of soda, muriate
of potash, and sulfate of potash, a method of guar-
anteeing is used which is based upon their purity as
chemical salts. That is, when pure they contain 100
per cent of the specific salt, and the guarantee accom-
panying the commercial product is simply a statement
indicating their purity. For example, when nitrate of
soda is guaranteed to contain from 95 to 97 per cent
pure nitrate, it means that it is 95 to 97 per cent
pure, or that 3 to 5 per cent of the substance consists
of impurities; it is not absolutely pure nitrate of
soda. Hence, the minimum percentage of nitrogen
guaranteed is 15.65 per cent, or 95 per cent of 16.47,
the per cent or pounds per hundred of nitrogen con-
tained in pure nitrate of soda. When muriate of
potash is guaranteed 80 per cent muriate, it means
that 80 per cent of the salt consists of pure muriate
of potash, and because pure muriate of potash con-
tains 63 per cent of actual potash, or potassium oxide,
the actual content of potash is derived by maultiply-
ing the 63 per cent, which the pure salt contains, by
80 per cent, and the result, 50.5 per cent, represents
136 FERTILIZERS
the amount of actual potash guaranteed. Sulfate of
potash, high-grade, is usually guaranteed to be 98
per cent pure, and since pure sulfate of potash con-
tains 54 per cent of actual potash, the content
of actual potash, or potassium oxide, guaranteed is
found by multiplying the 54 per cent by 98 per cent.
The following illustrations show the two methods of
stating the guarantees of raw materials and of mixed
fertilizers
Raw Materials
GUARANTEE ON BASIS OF PURITY
Nitrate of soda... . . . 98%, or containing 98 % pe nitrate
Muriate of potash ... .80%, ‘ uf 80 % muriate
Sulfate of potash. .... 98%, ** sp 98% ‘‘ sulfate
TRNESH ooh pee ce. Se ee ee 8 25% ‘* sulfate
GUARANTEE ON BASIS OF ACTUAL CONSTITUENTS
Nitrate of: soda, total nitrogen i... & 2°. ¢2 we 6 = 2 . . este
Marisate.of potash; actual potash... .) «0 stel. & fee 50.50 %
Sulfate of potash, actual potash. 54... (s—.) mean . . 53.00 %
Mixed Fertilizers -
GUARANTEE ON BASIS OF EQUIVALENTS IN COMBINATION
Nitrogen (equivalent to ammonia). . . win ae el SS eee
Available phosphorie acid oon glen to pond phos-
phates Or Lin). 5 x. ws) aabee hes pe ee cere oe -. 18 to. 22%
Potash (equivalent to aiitate of a ie a> one St ee
GUARANTEE ON BASIS OF ACTUAL CONSTITUENTS
Nitrogen Chota): 0 Ye. pie ue 23 2 eee ee
Phosphorie acid (available) Ni MAG ee aie ee 8.00 to 10.00 %
Potash (actual). . 2. 21 1 ee ee ee 5.50 to 6.50%
INTERPRETATION OF GUARANTEES 137
The guarantees of the raw materials mean prac-
tically the same in the first as in the second case. In
the first, the percentages given indicate the purity of
the chemical salt; while in the second, the figures
given indicate the actual content of the constituent
contained in the chemical salt. In large commercial
transactions, the sales are frequently made on the
basis of certain purity percentages; as, for example,
muriate of potash is sold at so much per ton on the
basis of 80 per cent muriate. If the analysis shows
it to contain less than 80 per cent, then the price
paid per ton is less in proportion to such deficiency.
If it is shown to contain more than 80 per cent, the
purchaser pays for the excess at the same rate. In
round numbers, a ton of muriate on the 80 per cent
basis contains 1,000 pounds of actual potash; if the
price is $40 per ton, the cost per pound is 4 cents.
If analysis shows but 900 pounds instead of 1,000,
the price paid per ton, at 4 cents per pound, is $36.
If, on the other hand, it is shown te contain 1,100
pounds, the price paid per ton is $44. Purchase
made when this method of guaranteeing is used is
practically equivalent to the “unit” basis, though, as
already stated, unless it is thoroughly understood, it
is likely to be misleading.
What has been said of the different statements
of guarantees of the raw materials, is also true in
the case of the mixed goods. In the first, the per-
centages of the elements that are given represent the
amounts when they exist in combination with other
elements: nitrogen, as ammonia; phosphoric acid,
1388 FERTILIZERS
as bone phosphate, and potash, as sulfate. While
in the other, the percentages given indicate the con-
tent of the actual constituents: namely, nitrogen,
phosphorie acid and potash.
The Advantages and Disadvantages of Purchasing Raw
Materials and Mixed Fertilizers
In the purchase of fertilizers, therefore, two meth-
ods may be adopted: First, the buying of fertiliz-
ing materials, as distinct from fertilizers, which fur-
nish single constituents like the standard high-grade
products, or which furnish one or two of the con-
stituents, like ground bone, tankage, fish, and the mis-
eellaneous products; these are called “incomplete,”
because they do not furnish all of the three essential
constituents. Second, the purchase of the mixed
manufactured brands, which contain all of the three
essential constituents, nitrogen, phosphoric acid, and
potash, which are prepared to meet the demands of
different soils and crops, and are called “complete,”
because containing all of the essential manurial con-
stituents, or those liable to be lacking in any soil.
The relative advantage of these different methods
of purchase depends, first, upon the cost of the con-
stituents, and second, upon the use that is to be
made of them.
It may be urged that, on theoretical grounds, there
are no good reasons why nitrate of soda, sulfate of
ammonia, dried blood, superphosphates and potash
compounds should be mixed, as the manufacture of
DIFFERENT METHODS OF PURCHASE 139
these does not improve or change the quality of the
constituents—it consists chiefly in simply grinding,
mixing and bagging. There are, however, advan-
tages and disadvantages in both methods of purchase,
the chief of which are stated below.
The advantages in the purchase and use of raw
materials are :*
1. A better knowledge of the kind and quality
of plant-food obtained. That is, these products
as a rule possess characteristics which distinguish
them from others and from each other, and they
are more likely to be uniform in composition than
mixtures.
2. It enables the use of one or more of the con-
stituents as may be found necessary, thus avoiding
the expense of purchasing and applying those not
required for the particular crop or soil. The farmer
is also enabled to adjust the forms and proportions
of the various ingredients to suit what he has found
to answer the needs of his soil or crop.
3. A saving in the cost of plant-food, since in
their concentrated form, the expenses of handling,
mixing and rebagging are avoided.
The chief disadvantages are :
1. The materials are not generally distributed
among dealers, and thus not so readily obtained.
2. It is difficult to spread evenly and thinly pro-
ducts of so concentrated a character, particularly the
chemical salts, which, unless great care is used, may
ee
** First Principles of Agriculture.”
140 FERTILIZERS
injure by coming in immediate contact with the roots
of plants.
3. The mechanical condition or degree of fineness
is less perfect than in the manufactured products.
The advantages in the purchase and use of com-
plete manures are:
1. They are generally distributed, and can be pur-
chased in such amounts and at such times as are con-
venient.
2. The different materials may be well propor-
tioned, both as to form of the constituents and their
relative amount for the various crops.
3. The products are, as a rule, finely ground and
well-prepared for immediate use.
The chief disadvantages are :
1. That it is impossible to detect in a mixture
whether the materials are what they are claimed to be.
2. That without a true knowledge of what consti-
tutes value, many are led to purchase on the ton basis,
without regard to the quantity and quality of the
plant-food offered. }
There is no question that the actual cost of
the constituent is less when purchased in the fertiliz-
ing material than in the manufactured brand, as not
only the expenses of mixing and bagging are saved,
but the cost of handling the product per unit of
plant-food is much less in the highly concentrated
materials than in mixtures made up of both classes
of fertilizing materials.
In the purchase of fertilizers by the second method,
the cost of the constituents is not only higher on the
HOME MIXING 141
average, but the variations in their cost are very
much greater, due to the differences in the charges
made by the different manufacturers for handling and
selling their products.
HOME MIXTURES
The fact that fertilizing materials are a regular
article of trade, and may be purchased as such, and
the fact that a complete fertilizer, so-called, is really
only a mixture of the various manufactured fertilizing
materials, has suggested the use of what are called
“home mixtures,”—that is, their mixing by the
farmer himself. This has proved to be very satisfac-
tory under proper conditions, since, as already stated,
the cost of the constituents is much less than if
secured in the average manufactured brand (often
from 25 to 50 per cent), and the mixing can be per-
formed by the regular labor of the farm, and thus
not add directly to the cost of the constituent.
This matter of home mixtures has been carefully
studied by a number of the experiment stations,
notably Connecticut, Rhode Island and New Jersey.
The results of their studies are published in their
regular reports, and show that the materials can be
evenly mixed on the farm, that the mechanical con-
dition is good, and that the results obtained from
their use are entirely satisfactory. It must be remem-
bered, however, that whatever method of purchase is
used, the object should be to obtain the kind and
form of constituent best suited to the conditions
142 FERTILIZERS
under which they shall be used, at the lowest price
per pound.
In any method of purchase which contemplates
the use of a mixture, care should be taken in the
selection of the brand or of the formula, since in
mixtures as well as in the raw materials, there are
two grades, the high-grade and the low-grade—
high-grade in the sense that in quality the con-
stituents are all good, and in the sense that maxi-
mum quantities are contained; and_ second, high-
grade only in that constituents of good quality
are furnished. They may be low-grade in the sense
that both the’ quality and amount of constituents
contained are low, and also in the sense that only
the quality of the constituents is low, the quan-
tity being sufficiently high.
Formulas
The following formulas are used for the sole pur-
pose of illustrating the differences that may exist
between high-grade and low-grade mixtures, and not
as indicating what should be used to make a good
or poor mixture:
ForRMULA No. 1
Nitrate of soda . . 500 lbs. furnishing 80 lbs. nitrogen
High-grade super-
phosphate ..1,100 ‘‘ : 180 ‘‘ phos. acid avail.
Muriate of potash, 400 ‘‘ a 200 ‘* potash
Totsha ys. 2,000 ‘' rr 460 ‘* total plant-food
FORMULAS 143
With a guaranteed eomposition of :
Nitrogen .. . OF ay eee pee ey)
Phosphoric acid available) a ere, eae aan
ere, se ses potash. hs ae haaa iets rohae 10% «
FoRMULA No. 2
Nitrate of soda... 250 lbs. furnishing 40 lbs. nitrogen
High-grade super-
phosphate . .1,000 ‘‘ 7 160 ‘* phos. acid avail.
Muriate of potash, 80 ‘‘ = 40 ‘* potash
Make-weight . . . 670 ‘‘ Hi
oo i Se 2,000 ** 2 240 ‘‘ total plant-food
With a guaranteed composition of :
ret hee gaa daa ane
Phosphorie acid tecnitable) as eee Pease 07
PND eye oa ee 2 yt ote =," Ooms oes
FoRMULA No. 3
wee 30 lbs. nitrogen
WeEGSO os ss. 600 Ibs. furnishing | da"! - phosphono adil
Mageaees =... 400 f ue 50 ‘* potash (actual)
Make-weight . . .1,000 ‘‘ .
J a 2,000 “* =« 170 ‘‘ total plant-food
With a guaranteed composition of :
EAE BSS Saeco a le re Oe
RGMMOnG AGG 0. 66 gs ls 2 este ce 4.5 %
EceateCbIA |) 6.5. ae 8 oles er Re
ForRMULA No. 4
EO 60 lbs. nitrogen
Mankaee ./. 3! :
ankage 1,200 Ibs furnishing |) lations iis nied
Le are B00,“ a 100 ‘‘ potash (actual)
Motals) jie. 2.000 ** 340 ‘‘ total plant-food
144 FERTILIZERS
With a guaranteed composition of :
TRRGReRE eS en, he Ce a Oe 3%
PROppHONG BCIG... 20. a ss a Ee ee 9%
Piuaale. oe ah, ee. el he ke ee a ee 5 %
Formula No. 1 shows a high-grade product, both
in respect to quality of plant-food and concentration,
while No. 2 is high-grade only in respect to quality.
In order that the plant-food may be distributed
throughout a ton of material, it is necessary to add
what is called “make-weight,” or a diluent. These usu-
ally consist of substances that possess no direct fer-
tilizing value. High-grade mixtures cannot be made
from low-grade materials, and low-grade mixtures
cannot be made from high-grade materials without
adding “make-weight.” The advantages of high-
grade products are concentration and high quality
of plant-food.
It will be observed that formula No. 1 contains
nearly twice as much plant-food as No. 2, or, in
other words, it will require about two tons of a fer-
tilizer made according to formula No. 2 to secure the
same total amount of plant-food as is contained in
one ton of No. 1. Now, the material in No. 2, other
than the actual plant-food, is of no direct ferti-
lizing value,—it is of no more value as a fertilizer
than the soil to which it is applied,—but the
actual cost of the constituents is considerably in-
creased, because the expenses of handling, bagging
and shipping are just double what they would be
ror Nor a.
DISCUSSION OF FORMULAS 145
Formula No. 3 illustrates a low-grade fertilizer in
the sense that it contains the poorer forms of the con-
stituents, and furnishes a comparatively small total
amount of plant-food. The nitrogen is all in the
organic form, and is derived from tankage, which,
while not the poorest, is poorer than other forms of
organic nitrogen. The phosphoric acid is also in
organic combination, and, while useful under many
conditions, is less useful for certain other conditions
than the soluble in Nos. 1 and 2. The potash, while
soluble, is derived from kainit, which, because of its
large content of chlorin, is regarded as less desirable
for certain crops than the more concentrated materials,
muriate, or the high-grade sulfate, which is free from
chlorids. It would require more than 2% tons of a
mixture made according to this formula to furnish as
much total plant-food as would be contained in a
mixture made according to formula No. 1, besides the
disadvantage of the lower quality of the constituents.
Formula No. 4 illustrates a mixture which, while
rich in total constituents, is not high-grade in its
quality.
All of these considerations should, therefore, be
carefully observed in the purchase of mixtures, or even
in the purchase of raw materials for home mixtures,
and the analysis, if properly made, will give positive
evidence on these points.
The expensiveness of low-grade fertilizers, as repre-
sented by formulas Nos. 2 and 38, is not fully appre-
ciated by the purchaser in all cases. He does not stop
to think that it is quite as expensive to handle the
J
146 FERTILIZERS
material which contains no plant-food as 1b as) ae
handle material which is rich in plant-food.
The Cost of Handling “ Make-weight”
A comparison of the advantages of low-grade and
high-grade mixtures in this sense of total quantity of
plant-food may be illustrated as follows: :
It has been shown by continued studies at the New
Jersey Experiment Station that the charges of the
manufacturers and dealers for mixing, bagging, ship-
ping and other expenses are, on the average, $8.50 per
ton; and also that the average manufactured fertilizer
contains about three hundred pounds of actual fer-
tilizing constituents per ton. A careful study of the
fertilizer trade indicates that these conditions are also
practically true for other states in which large quanti-
ties of commercial fertilizers are used.
A mixture of formula No. 1 would contain 460
pounds of actual available fertilizing constituents per
ton—160 pounds, or over 50 per cent more than is
contained in the average manufactured brand. That
is, a farmer purchasing a brand similar to formula
No. 1 would secure in 2 tons as much plant-food
as would be contained in 3 tons of the average man-
ufactured brand. Assuming that the charges per
pound of plant-food at the factory, and the expense
charges, are the same in each ease, and also that the
quality of plant-food in the one is as good as in the
other, the consumer would save $8.50 by purchasing
two tons of the former instead of three tons of the
CONCENTRATED FERTILIZERS 147
latter. In a few states the consumption of fertilizers
reaches nearly 100,000 tons annually, while in many
it ranges from 30,000 to 50,000 tons.
Thus is shown the very great saving that may be
effected in the matter of the purchase of fertilizers
from the standpoint of concentration alone, or, in
other words, the importance of a definite knowledge
of what constitutes value in a fertilizer. This saving
may be accomplished, too, without any detriment to
the manufacturer, since the difference to him between
making high-grade or low-grade goods, in reference
to concentration, is largely a matter of unskilled labor.
The manufacturers are in the business to cater to the
demands of the trade. If consumers are intelligent,
high-grade rather than low-grade goods will be pro-
vided by the manufacturers. Furthermore, as already
indicated, high-grade in the matter of concentration
means high-grade in quality, for high-grade mixtures
cannot be made from low-grade products.
GENERAL ADVICE
As farmers understand more fully the question of
fertilization, and as intensive methods of practice are
adopted, the tendency in the purchase of fertilizers
will undoubtedly be toward the first method, or the
purchase of fertilizing materials, rather than mixtures,
or at any rate, of high-grade special mixtures, rather
than what are now termed “standard brands,” which
are, aS a rule, low-grade in the concentrated sense.
‘This tendency will come, first, because intensive prac-
148 FERTILIZERS
tice requires a larger use of all of the constituents,
and second, a greater need in the growth of certain
crops of specific or dominant elements, and thus better
results are obtained from the application of single
constituents, or the use of special formulas, than in
“extensive” practice, in which the object is more to
supplement the soil supplies than to fully provide
for all the needs of the plants for food. |
The tendency toward codperative buying on the
part of small farmers will increase as it has done in
those countries in which there is a larger use of
fertilizers than here, though the method is already in
suecesstul operation in certain sections of the country,
and with very gratifying results. In this method of
direct purehase, the manufacturer and the consumer
are brought into closer relations with each other.
Transactions are based upon the transfer of a definite
number of pounds of a specific kind and form of
plant-food, rather than upon some mysteriously re-
markable qualities that are claimed, and are by many
supposed to be inherent in certain mixtures.
CHAPTER VIII
CHEMICAL ANALYSES OF FERTILIZERS
A COMPLETE chemical analysis of a fertilizer shows
not only the total amount of the different constituents
contained in a brand, but the form in which they
exist, and in most cases, the source of the materials
used is also indicated.
THE INTERPRETATION OF AN ANALYSIS
An analysis may show simply the total amount of
the constituents. This is not a sufficient guide as to
the value of a mixture, for while it is not possible to
indicate absolutely by analysis whether the organic
nitrogen, for example, is derived from blood (which is
one of the best forms), or from horn meal (one of the
poorer forms), it is possible to show whether the nitro-
ven is derived from nitrate or from ammonia, whether
the phosphoric acid is derived from a superphosphate
or a phosphate, and whether the potash present is in
the form of a sulfate or of a muriate. A high-grade
or a low-grade fertilizer, for example, may be distinctly
indicated by the analysis, since it is of a high-grade
if the three forms of nitrogen are present, if the total
phosphoric acid is chiefly soluble in water, and if the
potash has been derived from a sulfate or from a
(149)
150 FERTILIZERS
muriate. On the other hand, if the analysis shows
that the nitrogen is all in the organic form, that only
a minimum percentage of the phosphoric aeid is
available, though not soluble, and that a high econ-
tent of chlorin accompanies the potash, it is a low-
erade product, in so far as the form of the constituents
is concerned. The following statements of analyses
of two brands, showing the same total content of
constituents, illustrate this point:
ANALYSIS No. 1
Nitrogen, -as-nitrate .. 5 is. .04 nS
sie SUEY TISASINI a Se 3 YS, yo
os ** organic mater... 6 de
Ail: wh so sce. 4-5 ok a ee Oe ee
Phosphoric acid, soluble. . . . .. .8%
on Re cei) Ee Reren rs RL?
sib A eG UTE we ieee, 5 Oe
Topalcayaileabie leo. 54 Stee eee
Peabimes eS ee hl oes otk ae Rs Ce
CST SS ae ATT eee ee A eS
ANALYsIS No. 2
Nitrogen, as nitrate .
(6 ce
ammonia . Ai eh DIS
ae ‘organise mather ..2° .-4 4.88
Aik] 1 aes ey Lee ae re ee. eae
Phosphorie acid, soluble. . sak eet ee Me
35 iS SERVES 5 oe eee
is Pe. Gaoha bbe: oie el ee ee
Total avilable << 5% es aS Bee
PeGtaBh cP so. 7e park Boe me cack he oe
Ohilorig: --.5- 0 a TAS ee ae ee
A study of these two statements of analyses shows
that the total contents of the constituents are identical,
VALUE OF A CHEMICAL ANALYSIS 151
3, 10 and 5, respectively, in each case. That is, so
far as the total amounts are concerned, one brand
furnishes as much as the other, and from that stand-
point alone it is as good as the other; but it has been
already shown that the value of a fertilizer depends
not only upon the total content of its constituents,
but upon the form in which they exist. In the first
brand it is found that two-thirds of the total nitrogen
exists in the soluble form, equally divided between
nitrate and ammonia; the remaining third is in the
organic form, and may be derived from blood, or from
some low-grade materials. It is to be fairly presumed,
however, that when thus associated with so high a
proportion of soluble nitrogen, it is in a good form, as
the manufacturer has given evidence of his intent by
his liberal use of other good forms.
In the ease of the phosphoric acid, it is shown
that of every 100 pounds of the total, 80 pounds are
soluble, 10 reverted, or nine-tenths of the whole is
available; 10 pounds of every hundred only are in-
soluble, which is not only an indication, but positive’
proof, that the phosphoric acid is derived from a
superphosphate.
In the ease of potash, the chlorin associated with
it is but % per cent, indicating that it has been drawn
from high-grade sulfate, since kainit and muriate
are rich in echlorin, while in a high-grade sulfate no
appreciable amounts of chlorin are present.
In the second statement, all of the nitrogen is
shown to be in the form of organic matter. It may
be derived from blood, though it is not likely to have
152 FERTILIZERS
been drawn from this source, since of the total
phosphoric acid but 20 pounds per hundred, or one-
fifth, is available, and that is reverted rather than
soluble, indicating that the phosphoric acid must have
been drawn from tankage or from bone, or other ma-
terials which contain reverted but no soluble phos-
phorie acid, and which also contain a considerable
percentage of nitrogen. The phosphoric acid was cer-
tainly not drawn from a superphosphate, or it would
have shown a higher percentage of available, a cer-
tain proportion of which would have been soluble, and
the percentage of insoluble would have been very much
less. In the ease of potash, it is quite evident that
it was drawn from kainit, inasmuch as the percentage
of chlorin exceeds the percentage of the potash, as
would be the ease if the potash had ip drawn from
that source.
Thus it is that a complete chemical analysis of a
fertilizer indicates very clearly the source of the
materials by the form in which the constituents exist
in the mixture.
THE AGRICULTURAL VALUE OF A FERTILIZER
It is obvious, from what has already been pointed
out, that the value of a fertilizer to the farmer
_ depends not so much upon what is paid for it as upon
the character of the materials used to make it. This
value is termed the “agricultural value,” and it is
measured by the value of the increased crop produced
by its use. It is, therefore, a variable factor, depend-
AGRICULTURAL VALUE OF A FERTILIZER 153
ing first, upon the availability of its constituents, and
second, upon the value of the increased crop produced.
For example, in the first place, the agricultural
value of a pound of soluble phosphoric acid is likely
to be greater than that of a pound of insoluble when
applied under the same conditions as to soil and crop,
because in the one case the element is in its most
available form, while in the other it is least available.
In the second place, the soluble phosphoric acid may
exert its full effect and cause a greatly increased yield
on a certain crop, and still not cause an increase in its
value sufficient to pay the cost of the application,
while for another crop the same application may
result in a very great increase in the value of the
erop. The character or form of the materials used in
a mixture, as well as their suitability for the crop
must, therefore, be carefully considered in the pur-
chase of fertilizers. Slow-acting materials cannot be
expected to give profitable returns, particularly upon
quick-growing crops, nor expensive materials such
profitable returns, when used for crops of relatively
low value, as for crops of relatively high value.
THE COMMERCIAL VALUE OF A FERTILIZER
This agricultural value is, however, separate and
distinct from what is termed “commercial value,” or
cost in market. This value is determined by market
and trade conditions, as the cost of production of
the erude materials and the cost of their manufacture
and sale. Since there is no strict relation between
154 FERTILIZERS
agricultural and commercial or market value of a fer-
terlizer constituent, it frequently happens that an
element in its most available form, and under ordi-
nary conditions of high agricultural value, costs less
in market than the same element in less available
forms and of a lower agricultural value. The cost of
production in the one ease is lower than in the other,
though the returns in the field are far superior.
It is manifestly impossible to fix an agricultural
value for any of the constituents that will be true
under the varying conditions of soil, crop and season,
and method of use, though the relative value of the
different forms under uniform conditions of use may
be fairly indicated, and the analysis is the guide as
to their form. The commercial value of the different
constituents in their various forms may, too, be fairly
indicated, and will vary according to variations in
trade conditions. If the wholesale jobbing price of
nitrogen as nitrate is 15 cents per pound, available
phosphorie acid 5 cents per pound, and potash 4 cents
per pound, these are the prices which the manufacturers
pay. Their increased cost in manufactured brands,
therefore, is In proportion to the cost of this work ;
hence their cost to the consumer at factory should
vary within reasonably narrow limits, due to varia-—
tions in cost of manufacturing in different localities.
An illustration of the commercial value is shown
by the following example: Suppose that nitrate of
soda costs or can be purchased at retail, in ton lots,
for $48 per ton, which is, then, its commercial value.
The commercial or trade value of the nitrogen is,
COMMERCIAL VALUE OF A FERTILIZER 155
therefore, 15 cents per pound, since a ton contains on
the average 320 pounds of nitrogen. Or, suppose
that the retail price of available phosphorie acid in
superphosphates is $1 per unit; this is its commercial
value, and hence the commercial or trade value of
the available phosphoric acid would be 5 cents per
pound, since a unit contains 20 pounds. It does
not follow that the application of a pound of nitrogen,
costing 15 cents, and, therefore, having a commercial
value of 15 cents, will result in an increased crop
worth 15 cents, or that the application of a pound of
phosphorie acid costing 5 cents per pound will result
in an increased crop worth 5 cents. The increased
returns in crop from their use may be very much
greater or much less than the cost of the constituents,
depending upon the kind of crop and the skill of the
user. In the purchase of materials, however, a com-
mercial valuation is a guide as to the cost of the con-
stituents from different manufacturers or dealers; and
in many states a system of commercial values for
mixed fertilizers has been fixed, which, when properly
understood, is a useful method of comparison of the
different brands.
This method is based upon the fact that at points
of supply a pound of nitrogen, in the form of nitrate,
of ammonia, or of definite organic compounds, or a
pound of available phosphoric acid, or of potash in
the form of muriate or sulfate, is practically the same
to all manufacturers. That is, these cost prices, or
trade values, when applied to the constituents in the
mixture, represent their commercial value before they
156 FERTILIZERS
are mixed to form complete fertilizers. Hence, the
difference between the valuation of a brand on this
basis and the cost to the consumer represents the
charges, including profit, for mixing, bagging, ship-
ping and selling the goods.
The commercial or trade value for each of these
constituents is obtained, as already indicated, by
simply calculating the cost, using two factors, —
the wholesale prices for the different materials con-
taining them, and their average composition. To
this cost is added a certain percentage, to represent
the cost of handling and distribution in small lots.
Thus the trade value corresponds as nearly as may
be with the cost of the constituents to the farmer.
That is, the price fixed represents what the farmer
would have to pay the manufacturer for the con-
stituents in the material before it is mixed.
For example, suppose the wholesale price per ton
of nitrate of soda for the six months preceding’ March
1 is shown to be $40; the wholesale cost of nitrogen
in this form is, therefore, 12.5 cents per pound. To
this wholesale price may be added a certain sum to
cover the expenses of handling, usually 20 per cent,
thus making the retail price per ton $48, and the
_ trade or commercial value of the nitrogen 15 cents
per pound. That is, the $48 per ton, or 15 cents
per pound, represents the retail cost per pound of
nitrate nitrogen. This, if applied to the nitrogen as
nitrate, in the mixed fertilizer, will show what it
could have been bought for as nitrate in the unmixed
fertilizer. The values for the other constituents are
SCHEDULE OF TRADE VALUES $57
derived in the same way. These; together, make the
schedule of trade or commercial values of the con-
stituents which are used in the computing of the
commercial values of mixed fertilizers. The schedule
of values is revised annually, and, as nearly as pos-
sible, at the same time in the year. The following
schedule, used as an illustration of this point, was
adopted for 1898 by the states of New York, Con-
necticut, Rhode Island, Massachusetts, Vermont and
New Jersey:
SCHEDULE OF TRADE VALUES ADOPTED BY EXPERIMENT
STATIONS FOR 1898
Cts. per lb.
tomo das Miirahes . 6.6 Se ee atcha ts, eee
a ammonia salts wo... . Vike gel aur ameter
Organic nitrogen, in dried and fine- cand fish, meat and
blood, and in mixed fertilizers... . Beak «Oe
Organic nitrogen, in fine-ground bone and fahkaze* om cen eeees
= a ‘‘ eoarse bone and tankaget .... . . 10.0
Phosphoric acid, soluble in water. ..... i Bb Denar cs & hee
i 2 **) ammonium aioe. so ian
BS ‘* insoluble, in fine bone and ee scan sage
= o ns ‘* coarse bone and tankageft. . 3.5
4) 2 ‘* mixed fertilizers . ..°. 2.0
- eS ps ‘* fine-ground fish, cotton- abd
meal, castor pomace and wood ashes... ....... . 4.0
omaha Muriahe.... 2. 6 6 J Se hes ay, agelee, p as Men ae ened
- je emlfahe, and in. forms fea from muriates (or
UTA et AES oT ok ig, a, Spe od BEG oy eV emtat gees ta Ce
* Finer than 1-50 inch.
7 Coarser than 1-50 inch.
tIn New Jersey, the price for the soluble and reverted is identical; viz.,
4.5 cents, owing to the different method used in the determination of the
“reverted.”
158 FERTILIZERS
It will be observed that the schedule gives the
cost per pound of the different forms of nitrogen,
and of high-grade organic nitrogenous materials; of
nitrogen and phosphoric acid in ground bone and
tankage; of available phosphoric acid in superphos-
phates, and of actual potash in the potash salts, and
is a useful guide also in showing that the nitro-
gen, phosphoric acid and potash contained iu these
materials can be purchased in ton lots for the
prices mentioned. The valuations of mixed fertilizers,
obtained by the use of this schedule, are entirely
commercial; they are not intended to indicate even a
possible agricultural value. This point needs to be
emphasized, aS many are inclined to interpret them
as not only guides as to agricultural value, but as
positive statements of such value. It can be said,
however, that those who do so do not familarize
themselves with the discussions that usually aeccom-
pany reports of analyses. The different trade values
given for the nitrogen and phosphoric acid in the
two grades of bone represent their value in the form
of ground bone and of bone meal, products which
are distinctly recognized in the market, and which are
quoted at different prices. The coarser ground bone
is lower in price than the finer bone meal.
The accuracy of the schedule of values can be
shown by comparing it with the actual prices paid
for the constituents in the different materials, and
such comparisons as have been made from year to
year, by a number of the institutions exercising an
analysis control, show that manufacturers and dealers
OBJECTIONS TO COMMERCIAL VALUES 159
are willing to sell to farmers at prices corresponding
very closely with the schedule.*
A value is placed upon the insoluble phosphoric
acid in mixed fertilizers, not because all insoluble costs
the price given, but because in mixtures it is assumed
that the phosphoric acid is drawn from organic sources,
which do cost, at least, the price given.
There are arguments both in favor of and in oppo-
sition to this method of comparing the commercial
values of mixed fertilizers. The chief arguments in
opposition may be stated as follows: ‘
First, that the prices of these materials vary, and
hence in order to represent the actual commercial value
at the time the sales are made, they should be changed
as the markets change.
. Second, the valuations are misleading, because the
farmer does not clearly understand their meaning, and
is thus guided in his judgment of the usefulness or
agricultural value of a fertilizer by the stated com-
mercial value, as shown by this method, rather than by
the kind, form and proportion of constituents that
may be contained in it, and upon which its agricultural
value should be based.
Third, the chemical analysis does: not show abso-
lutely the sources of the materials, and thus it is
difficult to place a true commercial value upon a mix-
ture. This is especially true of organic nitrogen,
since because it is impossible to separate the amounts
that may be derived from different materials, a uniform
*See Bulletins Connecticut and New Jersey Experiment Stations.
160 FERTILIZERS
value is placed upon the total nitrogen found, whether
it is derived from the best forms, as dried blood and
dried meat, or whether derived from horn meal, ground
leather, or other low-grade forms of nitrogenous
material. This encourages the use of low-grade
products by unscrupulous manufacturers, to the real
detriment of the trade as a whole.
Fourth, that the commercial value so fixed mili-
tates against the use of certain kinds of good materials,
and in favor of certain kinds of poorer materials.
That is, a valuation of 2 cents per pound for insoluble
phosphoric acid in complete fertilizers, for example, is
a direct encouragement to include in the mixture a
considerable proportion of the insoluble phosphoric
acid from South Carolina, and other rock phosphates,
the value of which is ignored in commercial transac-
tions; while that price (2 cents) does not give a fair
value to the phosphoric acid contained in bone, tankage
and natural guanos, products in which the commercial
value of the insoluble is recognized,—that is, mixtures
which contain bone and tankage, and which furnish
phosphoric acid largely in an insoluble form. The
valuation fixed for this form is too low to fully
represent the commercial value of these goods. It is
also said that the trade value for available phos-
phoric acid in the mixtures encourages the use of
superphosphates from the rock phosphates, and dis-
courages the use of superphosphates from bone-black,
bone-ash and dissolved bone, because the trade or
commercial values represent the average cost of availa-
ble phosphoric acid in the superphosphates from all
THE ADVANTAGES OF VALUATIONS 161
of these, while the latter materials, because of actual
commercial conditions, cost more than the superphos-
phates from the former.
The chief arguments in favor are:
First, that it is not asserted that the system shows
absolutely the commercial value of each brand at the
time the sales are made, but the comparative com-
mercial value.
Second. They are not misleading. The commercial
valuations are not intended to be a guide as to the
agricultural value of a fertilizer. It is distinctly stated
in the reports of analyses that the comparative values
are purely commercial.
Third. It is a system which more nearly approaches
perfection than any other that has been devised, is
educative in its tendency, and is a safe guide, in the
majority of instances, as to the charges made for
mixing, handling and selling plant-food contained in
the different brands. If the analysis is properly in-
terpreted, as already indicated, it is the purchaser’s
fault if he buys poor forms of plant-food at a high
price. It is certainly a safer guide than mere name
of brand, and does not encourage the use of poor
materials.
Fourth. Any system of comparison of brands must
leave a great deal to the judgment of the purchaser.
He must interpret for himself whether he would rather
that his phosphorie acid were derived from one source
or another, whether he would prefer to pay a higher
price for insoluble phosphoric acid in acid phosphate,
and have the remainder soluble, than to pay the same
K
162 FERTILIZERS
or a greater price for the insoluble phosphoric acid in
bone, and have the remainder of it in the reverted
form. These conditions are again indicated by the
analysis which accompanies the valuation; the valua-
tions are, therefore, not to be used in total disregard
of the composition. If they are so used, it is not the
fault of the system. That it militates against the use
of high-priced superphosphates, if they are no better
than the lower-priced ones, is no argument against
the system, but rather for it, since it tends toward a
readjustment of the prices, a condition that must be
met in all competitive trades. Furthermore, the valua-
tion system has been effective in driving out materials
that are either fraudulent in their character or of very
low-grade. It is impossible to obtain a high valuation
on poor materials, and in the majority of eases de-
pendence upon valuations alone would be a safe guide
as to the comparative agricultural value of brands of
the same general composition.
CALCULATION OF COMMERCIAL VALUES
The following examples illustrate how commercial
values of complete fertilizers and of ground bone are
caleulated. The mixed, or complete fertilizer, contains
the three forms of nitrogen, three of phosphoric acid,
and the two forms of potash. In the -bone, it is
assumed that 50 per cent of the meal is finer than
1-50 inch, and is, therefore, regarded as fine, and that
50 per cent is coarser than 1-50 inch, and is, therefore,
regarded as coarse; and it is also assumed that the
CALCULATION OF COMMERCIAL VALUES 163
proportions of the nitrogen and phosphoric acid in
the fine and coarse is the same; also, that the analysis
shows the bone to contain 4 per cent of nitrogen and
20 per cent of phosphoric acid.
A Complete Fertilizer
it 2 3 4
Value Estimated value
% or lbs. Lbs. per lb. per ton of each
per 100 per ton cts. constituent-—
Maworen, AS nitrates... . . .1* 20= 20.K 13.0 = $2 60
- mmmoma salts . 1 < 20= 20 x 14.0 = 2 80
se erence matter. <= 20 « 14:00 = 2 80
Piigspnorie acid, soluble. . . 8 >< 20=160. < 4.5 = 7 20
= — Teavertot,... 1K 30 2=- 90. << Asa 90
oh oe SSeS. 6) 1 Ok Br OK Oa 40
Potash, as muriate 5 ee nO Ke ee 4 25
- Rm@@ipnae. 5~. 32 25 R201 5 = 5 00
Total estimated value per ton. ....... . $25 95
The first column shows the per cent of the con-
stituents contained, which, multiplied by 20, gives the
pounds per ton in the second column, which, multiplied
by the schedule prices per pound, gives the valuation
per ton, as shown in the fourth column.
Ground Bone
1 2 3 4 5 6 :
% or lbs. .% of Value Estimated
per _ fine- % or lbs. ‘Lbs. per lb. value
100 Ness per 100 per ton cts. per ton
, fe Re in ee. = 20== 40°. 15 = ee 49
Nit :
eee | ft X50: Bin coarse 6 20 =: 40. K--10.0 “= * 4°00
Phosphoric (20 K 50=10infine. * 20—200 K 4.0 = 800
acid . (20 K 50—10 in coarse. xX 20—=200 K 3.5 = 700
otal estimated value per ton... .... 03 8. - .- 1 $2440
164 FERTILIZERS
The first column of figures shows the per cent,
or pounds per hundred, of the constituents, which is
multiplied by the percentage of fineness, which gives
the percentage or pounds per hundred of fine or
coarse in the third column. The calculation is then
finished as in the case of complete fertilizers.
THE UNIFORMITY OF MANUFACTURED BRANDS
Another point which consumers of fertilizers are
interested in is the reliability of the various brands.
That is, they desire to know whether a brand that
shows good forms of nitrogen, of phosphoric acid, and
of potash in one year may be depended upon to fur-
nish approximately the same the following year, or
whether the manufacturers change their formulas from
year to year to conform to the relative cost of the
different materials: that is, whether when nitrogen
is relatively expensive and phosphoric acid is rela-
tively cheap, they introduce a larger proportion of
phosphoric acid and a smaller percentage of nitrogen;
whether when organic nitrogen is cheap and nitrate
and ammonia nitrogen are dear, they change the pro-
portions of these to correspond with the difference
in price, in order to retain the same selling price.
This is an important point, since after a certain
brand has been shown to be better suited than
another to their conditions of soil, to change the
formula, both in reference to the character and pro-
portions, may mean to the purchaser the difference
between profit and loss.
UNIFORMITY OF MANUFACTURED BRANDS 165
Evidence on this point can be obtained from the
reports showing the results of the analyses of the dif-
ferent brands from year to year, and a careful
study of these shows that genuine manufacturers of
fertilizers,—those who make it their sole business,
rather than a side issue or an adjunct to another busi-
ness,—can be fully depended upon in this respect.
They know that the farmer’s interest is their interest,
and that their sales will depend, other things being
equal, upon the increased crop results that the farmer
secures; that the permanency and success of their
business will depend upon the successful and profitable
use of their product; and that they cannot afford to
and do not change their formulas from year to year,
either in proportion or quality of constituents, to cor-
respond with the changes in price of the materials.
Their brands can be depended upon to furnish prac-
tically the same amount, kind and proportion of
plant-food from year to year.
The value of a fertilizer depends upon the kind,
quality and form of plant-food, as shown by the
analysis. Value does not depend upon who the manu-
facturer is, or what the statements may be concerning
the usefulness of special manipulation, nor to any
great extent upon special formulas, unless the farmer
has positive knowledge of the character of his own
conditions. Formulas derived both in kind and pro-
portion from the same materials will do equally well
under the same conditions. So far as the matter has
been investigated, there is no specific virtue added by
what is claimed to be the “blending” of the materials.
166 FERTILIZERS
In the whole matter of the purchase of fertilizers,
no guide, however good, can take the place of intel-
ligence on the part of the purchaser. This intelli-
gence must be exercised in the selection of forms of
plant-food, in the preparation of formulas, in the
interpretation of guarantees and of commercial values,
and in the method of using the fertilizer.
CHAPTER IX
METHODS OF USE OF FERTILIZERS
THE primary object in the use of a commercial fer-
tilizer is to receive a profit from the increase in the
yield of crops from the land to which it is applied;
and this may be derived either from the immediate
crop, or from the larger yield of a number of crops.
That the greatest immediate or prospective profit may
be gained, a wide knowledge of conditions which have
either a direct or indirect bearing upon the result is
~ essential.
CONDITIONS WHICH MODIFY THE USEFULNESS OF
FERTILIZERS
In fact, the controlling conditions surrounding the
matter are so numerous and so various that it is im-
possible, with our present knowledge, to lay down
positive rules for our guidance. At best, only sug-
gestions can be offered.
We may possess a full knowledge of both the kind
and form of existing fertilizer supplies, their cost and
the action under known conditions of the constituents
contained in each, as well as their maximum capability
for increasing the crop, but together with this knowl-
edge, it is essential that we should know how these
(167)
168 FERTILIZERS
facts and principles must be applied to each individual
crop, soil and condition, and yet even with this, abso-
lute certainty of profit is not guaranteed. A few of
the more important conditions which control the
profitable use of fertilizers are, therefore, briefly dis-
cussed, in order to arrive at a better understanding of
the practical suggestions and conerete examples given
in subsequent chapters. |
Derivation of Soil a Guide as to its Possible
Deficiencies
The first consideration is the soil itself, and its
influence. It is well known that a wide difference
exists in soils, both in reference to their chemical
character or composition, and to their physical proper-
ties, each having a direct influence in determining the
effect of any specific application of fertilizers. These
differences in soils are due to changes which were
wrought in the surface of the earth during its forma-
tion, and which are continuing in a small way at the
present time. It is believed that the original earth
crust contained all the minerals now found in it, but
that in the beginning they were distributed more uni-
fromly throughout its mass, and that the soils as they
exist at the present time, and as a result of the direct
disintegration of the original rock, represent a very
small area of the earth’s surface. They are not now .
constant, but variable in their character. The various
changes that have taken place during geologic time
have resulted in the breaking up of the original rocks,
SOILS DIFFER IN CHEMICAL COMPOSITION 169
a part having been separated mechanically and being
represented by various sizes of particles, and a part
rendered soluble. The fragments and the soluble por-
tions thus separated have not been deposited again in
the same proportions as they existed in the original
rock, which has caused a very wide variation in the
chemical composition of the different soil deposits.
The process and its results may be shown at the present
time in the wearing away of rocks. The harder,
sandy particles separate mechanically, and because of
the difference in the size of the particles, the coarser
are deposited as gravel or sand, in one place, and the
finer particles are deposited in another, making the
clay. The lime enters partly into solution and is de-
posited in another place, and so on, thus giving us
sandy soils, clayey soils and limy soils, all differing
- from each other in their amount and proportion of the
essential fertilizing constituents, as well as in their
physical qualities,—the sandy and gravelly making the
poorest soils because the particles consist very largely
of quartz, and the remainder being poor in phosphoric
acid or potash. The clay soils are frequently rich in
minerals containing potash, and poor in those con-
taining lime and phosphoric acid; and the limestone
soils are poor in potash and rich in lime, and fre-
quently in phosphates. In addition to these soils,
there are those that are made up largely of vegetable
matter, due to the accumulation of decaying growths.
These are frequently rich in nitrogen and poor in all
of the essential mineral constituents.
Hence it is that in the use of a commercial fertilizer,
170 FERTILIZERS
at least for certain crops, a knowledge of the nature
of soils in respect to the possible deficient element is
important, in order that those which exist in abun-
dance may not be added to, but that they may be sup-
plemented by such an abundance of the deficient ele-
ments as to permit the acquirement by the crops of
those necessary for a maximum growth. As a rule,
potash is a very essential constituent of manures for
sandy soils, not only because all crops require potash,
but because they require it in relatively large amounts,
and because in sandy soils it is lable to exist in
minimum amounts. Potash fertilization, therefore, is
especially useful on sandy soils. On the other hand,
in clay soils, which, as a rule, contain a very con-
siderable proportion of potash as compared with sandy
soils, the deficient element may be either phosphoric
acid or lime; and if these are supplied in abundanee,
the plant will be able to secure the necessary potash.
In a limy soil, the lime and phosphoric acid, and per-
haps the potash, may be in sufficient abundance to
cause a normal growth of plant, yet the nitrogen may
be so deficient as to prevent a normal growth.
Physical Imperfections of Sandy Soils
If it were possible to distinctly classify soils in
respect to their lack of one or more of the essential
constituents, it would be an easy matter to formulate
rules for our guidance in the fertilization of these
soils; but such is not the ease. Even sandy soils vary
widely in their chemical composition, as well as in
SOILS DIFFER IN PHYSICAL CHARACTER 171
their mechanical or physical properties, and certain
of them possess such a physical character as to make
it impossible to grow maximum crops even though
the essential elements are all supplied in sufficient
abundance. The constituent particles are too coarse,
and thus make the soils so open and porous that
they too freely admit the air, water and warmth, and
thus results a very rapid drying and heating of the
soil, with a premature ripening and burning of the
crops. The phosphates or the potash compounds ap-
plied are not readily fixed, and suffer an immediate
loss as soon as rain falls in such amounts as to
cause a leaching from them.
Physical Imperfections of Clay Soils
In elay soils, the physical conditions are quite the
reverse. All clay soils do not have the same general
composition, and they differ widely in their physical
qualities. Certain of them possess a reasonably good
texture, and permit the absorption of the food applied,
as well as its gradual distribution throughout the
mass by the percolation of the water through them;
while certain others are so compact, owing to the
finely divided particles, that even though they were
abundantly supplied with all or the necessary mineral
constituents, profitable crops could not be grown
because the roots could not readily penetrate, and
because the water falling upon the land would not
readily pass through, but remain upon the surface.
In the ease of soils with an abundance of lime,
172 FERTILIZERS
physical qualities also exercise a very considerable
influence, even though there is a sufficient supply of all
of the fertility elements. Certain of them are too cold,
others are too dry, and the mechanical condition is
such as to prevent the proper and uniform growth of
plants. It must be remembered, then, that only gen-
eral rules apply in the use of fertilizers upon soils of
the different classes, and that they are modified by
both the chemical composition and the mechanical con-
dition of the soils. The best use of a fertilizer,—that
is, the greatest proportionate return of plant-food in the
erop, all things considered,—is obtained from its ap-
plication upon soils that possess “condition,” or that
are well cultivated or managed. Full returns cannot
be expected when they are applied upon soils that are
too wet or too dry, too porous or too compact, or too
coarse or too fine. It is important that even the best
soils should be properly prepared, and it is infinitely
more important that those which possess poor mechan-
ical condition should be improved in this respect,
before large expenditures are made for fertilizers.
The Influence of Previous Treatment and Cropping
In the next place, the previous treatment and
cropping of soils should guide in the use of fer-
tilizers, since soils of the same natural character,
located equally well, will not always show the same
results from the application of fertilizers, because in
the one case the eropping has been such as to result
in the rapid exhaustion of one, rather than the three
INFLUENCE OF PREVIOUS CROPPING 173
specific fertilizer elements; while in the other, the
eropping may have been quite as severe, but has been
helpful because judicious rotations have been used and
improved methods practiced. It may be that in the
one ease, there may have been a continuous cropping
of wheat, for example, and only the grain sold from
the farm, in which ease there would be a much more
rapid exhaustion of the nitrogen and _ phosphoric
acid than of the potash; and if this continuous
wheat-cropping has been continued for a long time,
an application of the phosphates only may result in
quite as large an increase in crop as if both phos-
phates and potash salts were applied, because the
potash exhaustion has been less rapid than _ that
of the phosphoric acid, and the addition of potash
would simply add to the probably abundant quantities
already there. On the other hand, if the cropping
has been timothy hay, the removal of the potash
would have been greatly in excess of the phosphoric
acid, and consequently a fertilization with a greater
proportion of potash, or even this element alone, of
the minerals, may result in quite as large returns
as if the fertilization had consisted of both phosphorie
acid and potash. In fact, if the land had been
cropped continuously with tobacco, cotton, potatoes,
or other crop, there is likely to be a much larger
removal proportionately of some one element, rather
than proportionate amounts of all. This _ practice
results in a disproportionate removal of the constitu-
ents, and in order to bring the land back to its
eapacity for maximum production, or to equalize
174 FERTILIZERS
matters in this respect, it is necessary to add to the
soil the constituents removed in amounts in excess
of the others. On the other hand, the cropping may
have been such as to be fully as exhaustive in the
sense that the total quantity of constituents removed
is quite as great, though since they are removed in
more uniform proportions, the period of profitable
cropping is extended, and the fertility needed ineludes
all the essential elements, rather than one or two.
That is, the grain, hay and potatoes may have been
erown in rotation, each removing one or the other in
greater proportion, but because they differ with each
crop, no one is exhausted before the other; and thus
when the land reaches the time when it would no
longer profitably grow those crops, an application
then of all of the constituent elements would result in
a greater and more profitable increase in crop than
if the fertilizer contained one constituent only. The
previous treatment and cropping of soils, therefore,
is an important guide in determining the most
economical method of fertilization.
Furthermore, in this matter of cropping as a guide
to possible need of fertilization, it must be remem-
bered that a continuous one-crop practice is more
productive of total loss of constituents than a prac-
tice which includes such renovating crops as clover,
or one which permits of a more constant occupation
of the land, since in the former, the introduction of
clover reduces the need for nitrogen fertilization, and
in the latter, the vegetable matter is not so rapidly
used up, and the loss of mineral constituents by
INFLUENCE OF CHARACTER OF CROP 175
mechanical and other means is very much reduced,
because of the constant occupation of the land.
The Influence of Character of Crop
The financial result from the application of fer-
tilizers is also influenced in a very large degree by
the character of the crop itself, whether the value
of an increase in crop as great as can be expected
from a definite application is high or low; and on
this basis, crops may be elassified into two general
groups: first, those which possess a high fertility, and
which, as a rule, possess a relatively low commercial
value; and second, those which possess a low fertility
value and a relatively high commercial value. In the
first class are included the cereal and forage crops,
as corn, oats, wheat, hay, buckwheat, cotton and
tobacco, and in the second are included the various
vegetable and fruit crops. This classification, and
its importance, may be illustrated by the following
examples :
A ton of wheat, at $1 per bushel, will bring
$33.33. Its sale removes from the farm 388 pounds
of nitrogen, 19 of phosphoric acid, and 13 of potash.
At prevailing prices for these constituents, it would
cost $6.50 to return them to the farm.
A ton of asparagus shoots, at 10 cents per pound
bunch, will bring $200. Its sale removes from the
farm 6 pounds of nitrogen, 2 of phosphoric acid and
6 of potash, which could be returned for but little
more than $1.
176 FERTILIZERS
A ton of timothy hay will bring $10. Its sale
removes from the farm 18 pounds of nitrogen, 7 of
phosphorie acid and 28 of potash, amounts that
would cost $4.
A ton of apples will bring in an ordinary season
$20. It removes less than 3 pounds of nitrogen, 1 of
phosphoric acid and 4 of potash, which would cost
less than 60 cents to return to the land.
It is thus shown that crops lke wheat and hay
possess a relatively low commercial value, and yet
carry away, when sold, a very considerable amount
of the fertilizing constituents, while vegetables and
fruits, as illustrated by the asparagus and the apples,
have a high commercial or market value, and carry
away but minimum amounts of the fertilizing con-
stituents. This distinctive character of crops, while
not an absolute guide as to the profits that may be
obtained from the use of fertilizers,—since the cost of
production varies widely for each class,—is instruc-
tive in showing that those of a low commercial value
are more exhaustive than the other class, or those of
a high market value, and is certainly suggestive,
pointing out the necessity for judgment in the ap-
plication of fertilizers that shall be made in the
ease of crops of the different groups.
The Kind of Farming, Whether “ Extensive or Intensive”
Another very important consideration, and one which
exercises an influence, is whether the farming engaged
in is “extensive” in its character, or “intensive;”
CHARACTERISTICS OF GROWTH Ti
whether the purpose or idea is to simply supplement the
stores of plant-food in the soil, or whether the object
is to ensure an abundance of all forms of constituents
under all reasonable conditions, in order that a
maximum production may be secured.
PLANTS VARY IN THEIR POWER OF ACQUIRING FOOD
In the next place, the character or feeding capacity
of the plant and its season of growth should be con-
sidered, that systematic methods may be adopted, and
thus not only that waste of fertilizing materials may
be avoided, but that the applications may be made at
such times and in such amounts as will, other things
being equal, promote the greatest increase per unit
of applied food.
While each plant possesses individual characteristics
which distinguish it from all others, for our purpose
they may again be classified into general groups which
possess somewhat similar characteristics, particularly as
to their method and time of growth and their capacity
for acquiring food from soil sources.
Characteristics of the Cereal Group
The cereals possess distinct characteristics of
growth. The roots branch just below the surface, and
each shoot produces feeding roots, which distribute
themselves in every direction, and thus absorb food
from the lower layers of the soil as the plant grows
older. Because of their wide root system, and because
L
178 FERTILIZERS
of the character of their feeding rootlets, they are
able readily to acquire food from the insoluble phos-
phates and potash compounds of the soil, though they
are unable to feed to any extent upon the insoluble
nitrogen. Furthermore, inasmuch as the most rapid
development of many of these crops takes place early
in the summer, before the conditions are favorable for
the rapid changing of organic nitrogen into nitrates,
they are, with the exception of Indian corn (maize),
specifically benefited by early applications of nitrogen
in the form of nitrate. The corn, on the other hand,
which makes its most rapid growth after the other
cereals are harvested,—in July or August,— when
the conditions are particularly favorable for the de-
velopment of nitrates, do not usually require as large
proportions of nitrogen as of the mineral constituents,
particularly the phosphates. That is, wheat, rye, oats
and barley are specifically benefited by the early appli-
eation of quickly available nitrogen.
Characteristics of Grasses and Clovers
Forage crops, including both the grasses and clovers,
constitute another group, in so far as their use is con-
cerned, though possessing marked distinguishing char-
acteristics. Of the grasses, nearly all species are
perennial, though their length of life depends upon
the method of cropping and upon the character of
the soil. They send their fibrous roots into the sur-
face soil in the same manner as the cereals, though
they differ from them in forming a set of buds which
CHARACTERISTICS OF GROWTH 179
become active in the late summer and develop new
roots and shoots. They resemble the cereals in their
power of acquiring mineral food, and are even more
benefited by the application of nitrogen, since the
chief object in their use is to obtain the nitrogenous
substances contained in leaf and stem in the form of
pasture, forage or hay, rather than the matured grain.
Hence, nitrogen, which promotes this form of growth,
is an important constituent, and under any conditions
there should be a liberal supply provided.
The clovers, on the other hand, are not perennial,
with the partial exception of “white” or ‘Dutch”
clover, and with this exception they all possess a tap-
root, which penetrates downward, and as it descends,
throws out fibrous roots into the various layers of
soil. They are capable of readily acquiring their
mineral food, both because of their large root systems
and because of the character of the roots. They, how-
ever, differ in one very important particular from the
cereals and grasses, in that under proper conditions,
as already pointed out (p. 118), they are capable of
acquiring their nitrogen from the air. Thus with
liberal dressing of only phosphoric acid and potash,
maximum crops may be secured. They are “nitrogen
gatherers,” and the tendency of their growth is to im-
prove the soil for the nitrogen consumers, or for those
that obtain their nitrogen only from soil sources.
Root Crops
Another class of plants, differing from those already
described, includes the root crops, as beets, mangels,
180 FERTILIZERS
turnips and carrots. These plants cannot make ready
use of the insoluble mineral constituents of the soil.
Hence, in order to insure full crops, they must be
liberally supplied with available food. Of the three
classes of fertilizing constituents, the phosphates are
especially useful for turnips, while the slower- growing
beets and earrots require that the nitrogen shall be in
quickly available forms. The proper fertilization of
sugar beets, for example, is of great importance, since
not only is the yield affected by fertilization, but the
quality of the beet for the production of sugar.
White potatoes and sweet potatoes, the one a
tuber, the other an enlarged root, constitute another
class which does not possess strong foraging powers.
They require their food in soluble and available forms,
and with suitable soils potash is the ingredient that
is especially useful in the manures applied.
Market-garden Crops
Another group of crops is distinguished as a class,
not so much because of their peculiar habits of growth
as beeause of the objects of their growth, though
this latter fact has a very important bearing upon
economical methods of fertilization. This class in-
eludes what are called “market-garden crops,” as
lettuce, beets, asparagus, celery, turnips, cucumbers,
melons, sweet corn, beans, peas, radishes, and various
others. The particular object in raising these is to
secure rapidity in growth, and thus to insure high
quality, which is measured by the element of succu-
FRUIT CROPS A DISTINCT CLASS 181
lence. In order that this may be accomplished, they
must be supplied with an abundance of available
plant-food, and since nitrogen is the one element
which more than any other encourages and stimulates
leaf and stem growth, its use is especially beneficial
to all of these crops. They must not lack for this
element in any period of their growth, though, of
course, a sufficiency of minerals must be supplied in
order that the nitrogen may be properly utilized.
Because of their high commercial value, the quantity
of plant-food applied may be greatly in excess of that
for any other of the groups, and profits, as a rule, are
measured by this excess rather than by the proportion
of the elements.
Fruit Crops
Another distinct class of crops, though differing
materially in their individual characteristics, as well as
in their time and period of growth, are the fruits.
These differ from most other crops, in that a longer
season of preparation is required, in which the growth
may be so directed as to prepare the plant or tree for
the proper development of a different kind of product,
namely, fruit, as distinct from grain or seed in the
cereals, or succulence in the vegetable crops. The
fruit differs in its characteristics from the ordinary
farm crops, in that its growth and development require
a little different treatment, since it is necessary that
there shall be a constant transfer of nitrogen from the
tree to the fruit throughout the entire growing season.
The growth of each succeeding year of tree and fruit
182 FERTILIZERS
is dependent, not altogether upon the food acquired
during the year, but as well upon that acquired in the
previous year, and which has been stored up in bud
and branches. A knowledge of the habits of growth,
the period of growth and the object of the growth of
this class is, therefore, useful as a guide to the eco-
nomical supply of the essential elements of growth.
These crops must be provided with food that will en-
courage a slow and continuous rather than a quick
growth and development.
SYSTEMS OF FERTILIZING SUGGESTED
A careful review of the foregoing facts furnishes
abundant evidence of the impracticability of attempts
to give information concerning the use of fertilizers
that will apply equally well under all of the conditions
of farming that may occur. Nevertheless, there have
been a number of methods or systems of fertilization
suggested, each of which gg one or more points
of advantage.
A System Based Upon the Specific Influence of a
Single Hlement
The one which has perhaps received the most atten-
tion, doubtless largely because one of the first pre-
sented, and in a very attractive manner, is the system
advocated by the celebrated French scientist, George
Ville. This system, while not to be depended upon
absolutely, suggests lines of practice which, under
SYSTEMS OF FERTILIZING 183
proper restrictions, may be of very great service. In
brief, this method assumes that plants may be, so far
as their fertilization is concerned, divided into three
distinct groups. One group is specifically benefited by
nitrogenous fertilization, the second by phosphatie,
and the third by potassic. That is, in each class or
group, one element more than any other rules or
dominates the growth of that group, and hence each
particular element should be applied in excess to the
class of plants for which it is a dominant. In this
system it is asserted that nitrogen is the dominant
ingredient for wheat, rye, oats, barley, meadow grass, -
and beet crops. Phosphoric acid is the dominant fer-
tilizer ingredient for turnips, Swedes, Indian corn
(maize), sorghum and sugar cane; and potash is the
dominant or ruling element for peas, beans, clover,
vetches, flax and potatoes. It must not be understood
that this system advoeates only single elements, for the
others are quite as important up to a certain point,
beyond which they do not exercise a _ controlling
influence in the manures for the crops of the three
classes. This special or dominating element is used in
greater proportion than the others, and if soils are in
a high state of cultivation, or have been manured with
natural products, as stable manure, they may be used
singly to force a maximum growth of the crop. Thus,
a specific fertilization is arranged for the various
rotations, the crop receiving that which is the most
useful. There is no doubt that there is a good scien-
tific basis for this system, and that it will work well,
particularly where there is a reasonable abundance
184 FERTILIZERS
of all of the plant-food constituents, and where the
mechanical and physical qualities of soil are good,
though its best use is in “intensive” systems of prac-
tice. It cannot be depended upon to give good results
where the land is naturally poor, or run down, and
where the physical character also needs improvement.
A System Based Upon the Necessity of an Abundant
Supply of the Minerals
Another system which has been urged, notably by
German scientists, is based upon the fact that the
mineral constituents, phosphoric acid and_ potash,
form fixed compounds in the soil, and are, therefore,
not likely to be leached out, provided the land is con-
tinuously cropped. They remain in the soil until used
by growing plants, while the nitrogen, on the other
hand, since it forms no fixed compounds and is
perfectly soluble when in a form useful to plants,
is hable to loss from leaching. Furthermore, the
mineral elements are relatively cheap, while the nitro-
gen is relatively expensive, and thus that the eco-
nomical use of this expensive element, nitrogen, is
dependent to a large degree upon the abundance of
the mineral elements in the soil. It is, therefore,
advocated that for all crops and for all soils that are
in a good state of cultivation, a reasonable excess of
phosphoric acid and potash shall be applied, sufficient
to more than satisfy the maximum needs of any crop,
and that the nitrogen be applied in active forms, as
nitrate or ammonia, and in such quantities and at
MINERAL SUPPLIES ADVANTAGEOUS 185
such times as will insure the minimum loss of the
element and the maximum development of the plant.
The supply of the mineral elements may be drawn
from the cheaper materials, as ground bone, tankage,
ground phosphates and iron phosphates, as_ their
tendency is to improve in character; potash may come
from the erude salts. Nitrogen should be applied
chiefly as nitrate of soda, because in this form it is
immediately useful, and thus may be applied in frac-
tional amounts, and at such times as to best meet
the needs of the plant at its different stages of
growth, with a reasonable certainty of a maximum
use by the plants. Thus no unknown conditions of
availability are involved, and when the nitrogen is so
applied, the danger of loss by leaching, which would
exist if it were all applied at one time, is obviated.
This method also possesses many advantages, par-
ticularly where the “intensive” system is practiced,
though it is also useful in quickly building up worn-
out soils, or those naturally poor, because in any case
these must be provided with liberal supplies of the
minerals, and when these only are applied, the im-
mediate outlay is far less than if the expensive ele-
ment, nitrogen, were included; and a greater economy
in the use of nitrogen is accomplished if it is added
in small amounts when required. Besides, in the im-
provement of soils, the liberal application of the
minerals is conducive to an abundant growth of the
legumes, which are able to acquire their nitrogen
from the air, thus reducing to some extent the outlay
for this expensive element. This system is strongly
186 FERTILIZERS
recommended where cheap phosphatic and _ potassic
materials are readily accessible, as is the case in those
countries where it is successfully used.
A System Based on the Needs of the Plants for
the Different Elements as Shown by
Chemical Analysis
Another system of fertilization is based upon the
theory that the different plants should be provided
with the essential elements in the proportions in
which they exist in the plants, as shown by chemical
analysis. Different formulas are, therefore, recom-
mended for each crop, the constituents of which are
so proportioned as to meet its full needs. This
method, if care is taken to supply an abundance of
all the necessary constituents, may result in a com-
plete though perhaps not an economical feeding of
the plant, since it assumes that a plant which con-
tains a larger amount of one constituent than of
another requires more of that constituent in the fer-
tilizer than of the others. It does not take into con-
sideration the fact that the plant which contains a
larger amount of one element than another may pos-
sess a greater power of acquiring it than one which
contains a smaller amount.
Neither does this system take into consideration,
as already pointed out (p. 178), that the period or
time of growth of the plant also exercises a consider-
able influence in indicating the capability of the plant
to acquire its necessary food from the stores of the
FERTILIZING POT-PLANTS 187
soil, as may be illustrated by wheat and Indian corn,
which both contain a relatively high content of
nitrogen. Under good conditions of soil, wheat is
specifically benefited by heavy dressings of quickly
available nitrogen. Corn is not, and one reason is,
that they possess different powers of acquiring food,
due, to a considerable extent, to the difference in
their time of growth, as well as to the period or time
of their most rapid growth.
This method may, however, be applied with very
ereat advantage in greenhouse work, or in growing
market-garden crops, where the amounts in the soil
are not regarded as of importance, and excessive
amounts of all are added. The system has been
elaborated to a great degree of nicety for the grow-
ing of greenhouse crops, flowers, and foliage plants,
so much so that now artificial manure cartridges are
prepared, which contain the amounts and kinds of
food shown by the analysis of the different plants
to be needed for their growth and full development.
“The manure has the form of a fine powder, enclosed
within a metallic wrapper, and firmly compressed into
the shape of a cartouche or capsule, cylindrical in
form, about three-fourths inch across and one-half
inch in depth. It is simply thrust into the soil of
the pot to a depth of one-half or one inch, and
allowed to remain. After a time it is found that the
fertilizer gradually disappears, and at length nothing
is left but the little pill-box-like wrapper, which
originally contained the mixed fertilizing powder.” *
*«The Gardener’s Chronicle,” London, England.
188 FERTILIZERS
A System in Which the Fertilizer is Applied to the
“Money Crop” in the Rotation
Another system is also recommended, which is
well adapted for “extensive” farming, where the ma-
jority of crops which are grown in rotation possess
a high fertility value and a low commercial value,
and where one crop is regarded as the chief ‘ money-
maker.” The system demands that to this crop shall
be applied such an abundance of plant-food as to
insure a continuous feeding, and a consequent max-
imum production, even though adverse conditions
intervene. Thus by a liberal supply of food, a money
crop is secured which is as large as climate and sea-
sonal conditions will permit, though which does not
require all of the food applied. Hence the residue
may be depended upon to fully nourish the remaining
crops in the rotation, or at least the immediately suc-
ceeeding ones, thus saving direct outlay for them.
This system may be illustrated as follows:
On soils in good physical condition, and naturally
well adapted for growing potatoes, this crop is se-
lected as the “money-maker” in the rotation, which
consists of corn, potatoes, wheat, clover and hay.
The potato crop is fertilized so liberally, say with
1,500 pounds per acre of a fertilizer containing —
PION! 395), Cah bee agin OSes, ee emer ee 4%
Phosphoric acid: .: 38ers ee ce eee 6%
| ners wimee eres epee r kn see ot 10%
as to insure its maximum growth under average con-
ditions. The removal of a large crop would still
IRRATIONAL SYSTEM OF FERTILIZING 189
leave a large residue of plant-food, which would pro-
vide the following wheat crop with at least all of the
mineral elements necessary to produce a maximum
crop. If the wheat does not show vigorous growth in
the spring, it is lightly top-dressed with nitrate of
soda, which not only feeds it directly with nitrogen,
but strengthens and invigorates the plant, enabling
it to secure the minerals needed. The removal of a
large crop still leaves an unused residue, upon which
the clover crop following is also able to make a maxi-
mum growth, and thus three crops are fertilized with
the one application. The hay is either fertilized with
both the minerals and nitrogen, or lightly top-dressed
with nitrogen early in the spring. The yard manure,
accumulated from the residue of straw, hay and corn,
‘is applied to the corn, which, being a gross feeder,
is able to obtain from this an abundance. Thus, by
the heavy application of fertilizer upon the ‘money
erop,” all the crops in the rotation are benefited.
This method possesses many valuable features, and
is, perhaps, quite as well adapted as any other for this
system of farm practice.
An Irrational System
The most expensive and irrational system of all,
and one more commonly practiced than any other in
general farming, may be termed the “hit or miss”
system; if a “hit” is made, there is a profit, if a
“miss,” the loss is trifling. In this system, no special
thought is given to the character of the crop or its
190 FERTILIZERS
needs. If the farmer can afford it, he purchases a
fertilizer, without regard to its composition, and ap-
plies it in very small amounts. If it happens to con-
tain that element which is particularly needed for the
plant to which it is applied, a profit is secured. In
too many eases, however, the constituents added are
already in abundance in the soil, or so little of the
fertilizer is used as to preclude any profit.
SUMMARY
With the exception of this last system, there are
good features in all of these suggested methods of use,
and it rests with the farmer to select the best points
from each, or rather to use the suggestions in each
which are in his judgment more applicable to his con-
ditions. They are all based upon underlying principles,
and pre-suppose a knowledge of them on the part of
the farmer. They are, at best, but guides or sign-posts
pointing toward better methods in the use of fertil-
izers, rather than absolute rules to be blindly followed.
The suggestions here and in subsequent chapters,
in reference to the use of fertilizers, are formulated
from the best information obtainable by the writer,
and mainly from two sources: First, the results of
experimental inquiry, and, second, the results of the
observation and experience of practical men. In no
case can absolute rules be laid down. Farmers may
safely rely on the well-established principles, but each
must remember that the use of the principles must
be modified according to his own conditions.
CHAPTER X
FERTILIZERS FOR CEREALS AND GRASSES
Ir HAS already been pointed out (p. 175) that
these crops are classed as possessing a relatively low
commercial value and a relatively high fertility value,
and that, from a practical standpoint, in any fertiliza-
tion of them a possible profitable return should be
borne in mind. This is, of course, necessary in all
cases, but is particulary necessary where an increased
yield, as great as can be expected from an application
of proper fertilizing materials, cannot possibly result
in an extraordinary profit, a result quite possible with
certain crops of the opposite class. The possible in-
crease in yield, too is, dependent on the conditions of
soil and season, and if these latter are such as to
forbid a maximum increased yield, the immediate
profits from the application are considerably reduced.
It has been shown, too, by careful experiments,
that, on the average, at least one-third of the nitro-
gen applied to these crops, though contained in the
best forms, is not secured in the crop, even under
the most favorable conditions; that is, in any case
certain amounts are lost through drainage, the growth
of weeds and denitrification; and, further, that the
minerals must exist in the soil, or must be supplhed
in sufficient excess, otherwise, the utilization of the
(191)
192 FERTILIZERS
nitrogen by the plant is still further reduced. The
expense of fertilizer per unit of increase in these
crops is, therefore, relatively greater, even under the
best conditions of its use. A bushel of wheat, with
its accompanying straw, will contain, for example:
POP oo nk Ss is EN a ee 1% lbs.
PRGEAMOLIG ROME 66.0 ia ion a ae ee Be Ba
Paani A es 8 So eee se ee i Weare
It will be observed that the amounts of fertilizer
ingredients contained in the crop are such that, if the
seasonal conditions are perfect, so that the maximum
of the amounts applied are recovered in the crop, the
cost of fertilizers per bushel of increase is still rela-
tively high, thus showing that great care must be
exercised in order that a direct and immediate profit
may be secured. Nevertheless, since the cost of pre-
paring the land and of harvesting the crop is but
slightly greater for a large crop than for a small one,
the larger returns for the labor very frequently pay
well for the application of the material, even though
the margin of money profit is small. In crops of
this sort therefore, and especially when grown on
the “extensive” plan, an important point to be de-
termined is whether the land is deficient in all of
the constituents for grain and hay growing, or whether
only one or two are lacking, in order that in the ap-
plications made, only those constituents are supplied
that are necessary, and adding to an excess already
present is thus avoided, with a consequent saving in
the cost of the fertilizer.
FARMERS SHOULD EXPERIMENT 193
EXPERIMENTS TO DETERMINE THE LACKING
ELEMENT
The lacking element cannot be fully determined,
except by direct experiments by the farmer himself.
That is, no general principle can be depended on
as an absolute guide. He should learn whether his
soil is deficient in any of the elements, and, if so,
which ones should be applied to the different crops
in his rotation. <A careful study along this line, too,
will show whether it is fertilization that is required
to meet seeming deficiencies, for it frequently hap-
pens that the needs of the soil are not so much for
added plant-food as for better management of the
soil in other respects, in order that natural supplies
- may be made more available.
It may seem, at first glance, that experimenting
should be left to the experiment stations, and that
farmers should be advised by them in respect to the
needs of their soils in respect to plant-food. This
is partly true, but the proper function of experiment
stations is to establish principles, the application of
which must be left, in large part at least, to the
intelligence of those who are to utilize them. The
farmer must study his own conditions. Scientific in-
quiry has established the facts that soils differ in their
content of the different plant-food elements, and that
those of practically the same chemical composition
differ in respect to their physical qualities, both of
which conditions exercise an important influence upon
the availability of the constituents.
M
194 FERTILIZERS
This experimenting may also seem to be a trouble-
some operation, yet, if thoughtfully managed, it will
mean but little extra labor, and the resulting gain
may be far in excess of the cost of the work. For
example, if it is shown that fertilization under certain
conditions is not the thing needed, and, therefore, not
profitable, it saves possible outlay at once; if it shows
that the application of certain of the constituents is
a profitable practice, it enables the adoption of a
systematic scheme of fertilization.
A Scheme for Plot Experiments
The following simple scheme of plot experimenting
has been suggested, and it admits of determining
many of the points involved. This scheme includes
ten plots, in which three are to be cropped without
manure, as check plots, in order to show the produc-
tive capacity of the unmanured land. The plots may
vary in size, though it is desirable that they should
contain at least one-twentieth of an acre, and that
they should be long and narrow, in order to include
as many inequalities of the soil as possible, though
in any case land as uniform as possible in physical
and chemical qualities, and fairly representative,
should be selected. The following plan permits of a
study of the effect of the application of individual
constituents, and of their various combinations. If
desired, in order to simplify the work in the begin-
ning, only the first four plots need be taken. This
will reduce the labor, and, at the same time, permit
PLAN OF EXPERIMENTS 195
astudy of the soil’s deficiencies in respect to single
elements of plant-food, and the relative needs of
the different crops for the various constituents.
PLAN OF EXPERIMENTS— SIZE OF PLOTS, zo OF AN ACRE
Plot. 1. Check. No fertilizer.
Bertie § Mabraie-OL BOdG =. =. ls Sf ewe ap ee 8 lbs.
Dapllt. . SUperphosplate . .-. . 6+ #6 cee He 16-35
erry. Mineiaie of potash)... so 2 Oe5 se ae
‘Vv. Check. No fertilizer.
‘* VI. Nitrate of soda, 20 Ibs. Superphosphate. 16 ‘
[ Vit. ‘Witrate.of soda, 20 ‘‘ Potash. 2°... .-8- %
evi. Phoshorie: acid, 40-‘° Potash: 2... 805
‘¢ IX. Nitrate of soda, 8 ‘‘ Superphosphate, 16 ‘‘
UE SLL Se Mea er Waa ati eer Aree c a
Siete @ Check. No fertilizer.
The rate of application per acre is greater than
would naturally obtain in practice, in order both to
facilitate the distribution of the fertilizer, to furnish
a sufficient abundance of the constituent, and to pro-
vide against unfavorable conditions.
Preferably, the application should be made_ broad-
east, and before planting, if an uncultivable crop,
though for cultivable crops it may be applied later
and harrowed in.
It will be observed that the amounts of fertilizer
are one pound per square rod, or multiple thereof.
Thus, in order to insure an equal distribution over
the entire area, it may be roughly divided into plots
of a square rod, and the required material for each
rod applied separately. Careful weights should be
made of the yields of the different plots, as a basis
196 FERTILIZERS
of comparison. The same fertilizers should be used
on the different crops of the rotations, and, as inter-
est is inereased in the work, different forms and
amounts of the various constituents may be intro-
duced.
Results That May Be Attained
If it is found that for a certain crop only one of
the applied constituents profitably increases the yield,
then that should be used until the need of the others
is apparent. If two are needed to accomplish the
results, use two, and so on; though in the long run,
or as the practice approaches the “intensive” system,
all will doubtless be required. In “extensive” farming
this is a very desirable line of experimentation, and
ean be earried out by individual farmers. It is useful
not only in showing the deficiencies of the soil for
the various crops, but is educative in its character, as
it familiarizes the farmer with the materials that are
used in making fertilizers, and encourages exact
methods of work. Since, as already stated, the need
very frequently is not so much for added fertility as
it is for better preparation and cultivation of the soil,
or for amendments such as lime, it would be a desir-
able practice to inelude in the number of plots here
indicated one or two in which the cultivation of the
soil was made more perfect, in order to determine
whether the need is for more fertility elements or
whether it is for better tillage, the effect of which
is to render more of the soil constituents available to
THE RESULTS OF EXPERIMENTS 197
the plant. One or two to which lime is added may
be advisable, in order to determine whether this sub-
stance is needed either to correct acidity or to make
available otherwise unusable compounds. This method,
while particularly desirable where “extensive ” methods
of practice prevail, is of less importance where the aim
is to grow maximum crops, in which ease both the
crop and its rotation are to be considered, and the
needs of the plant rather than the deficiencies of
the soil require first attention.
The results of experiments which have been con-
ducted with great care in a number of states show
that where “extensive” methods are practiced certain
elements need not be added in the fertilizers; that
is, that the soil contains such an abundance of them
that the plant is able to obtain a full supply, at least,
for a long time. For example, it has been shown
that on the chief sugar-producing soils of Louisiana
and Mississippi, and the cotton soils of Georgia and
Texas, the addition of potash has been of less im-
portance in the past than the other elements, and _ it
frequently does not need to be ineluded in the fer-
tilizer, while phosphoric acid is always needed.
The results of field experiments on this plan in
New Jersey, on reasonably good, loamy soils, indi-
cate that phosphoric acid and potash are of much
more importance in fertilizers for corn than _ nitro-
gen, whereas upon sandy soils, nitrogen and potash
are of relatively more importance than phosphoric
acid; that is, even where “extensive” practice is used
there are conditions where one or more of the ele-
198 FERTILIZERS
ments are not required in order to secure maximum
crops, which eliminates the necessity for an imme-
diate outlay for those constituentS that are not
lacking. Where experiments of this sort have not
been carried out and the specific needs determined, it
becomes necessary to assume that all of the constituents
are required, and to apply the amounts and propor-
tions of those which the general considerations of the
soil, season, climate and crop would seem to demand.
As already pointed out, the methods of fertilization
here suggested, though in many instances apparently
positive, are not to be interpreted as absolute rules, but
rather used as guides, based upon the best information
that it has been possible to obtain, both as a result
of scientific inquiry and of practical experience.
THE IMPORTANCE OF SYSTEM IN THE USE OF
FERTILIZERS
The following rotation is assumed, in order to show
the necessity of a definite system of work, which is
quite as important in this branch of farming as in
many others in which system is apparently more
essential,—though in fact it is quite as necessary to
observe a definite system in the feeding of plants as
in the feeding of animals with the plants:
ILLUSTRATION OF A ROTATION
First year... .o.0 O-s-. 0.008 Maize-[earm).
Second years... pce. out © eee
Ehivt year oc. os 3 es Se eee
Fourth year...... . . . Clover and timothy
Fifth year... os «o. 4 ees.
SYSTEMATIC FERUILIZATION 199
Indian Oorn Exhaustive of the Fertility Elements
Since in rotations of this sort a fair number of live
stock is usually kept, a considerable amount of ma-
nure is made, which should be carefully cared for and
used, as it contributes materially to the success of the
plan. The manure may be used in part on land for
eorn, and should be spread broadeast, practically as
fast as made during the fall, winter and early spring.
This plant, because it is a gross feeder, and also
because it makes most of its growth during the sum-
mer season, when activities in the soil are most rapid,
is able to appropriate from the coarse manures a larger
proportion of the constituents than would be possible
for crops which make their greatest growth earlier or
- later in the season. In the summer, too, the condi-
tions are most favorable for nitrification, and soils
which possess a fair content of vegetable matter are
usually able to furnish the nitrogen needed in addition
to that supplied in the organic manures, particularly
in the middle and southern states. The considerable
amounts of potash required for the growth of stalks,
and the phosphoric acid for the formation of grain,
demand that a liberal supply of these constituents be
provided, and the fertilizer for the corn should, there-
fore, contain an abundance of available phosphoric
acid and of potash.
A crop of 50 bushels of shelled corn per acre, with
the accompanying stalks, will remove, on the average,
80 pounds of nitrogen, 29 pounds of phosphoric acid,
and 55 of potash. It is an exhaustive crop. A fer-
2900 FERTILIZERS
tilizer, therefore, that would furnish 30 pounds of
phosphoric acid and 40 of potash would be regarded
as a fair dressing for land of medium quality. <A part
of the phosphoric acid, at least, should be in a soluble
form, in order to supply the early needs of the crop.
The remainder may consist of ground bone or tankage,
if the phosphoric acid in these can be obtained more
cheaply, since they will decay rapidly enough to supply
the demands for the later growth. The potash may be
either muriate of potash or kainit, though the former
is preferable if it is applied in the drill, which is, if
used in these amounts, a perfectly safe practice so far
as injury to the plant is concerned; though fertilizers
containing large amounts of potash salts are preferably
applied broadeast on raw ground of a clayey nature,
and well worked into the soil, thus insuring a good
distribution. The cost of an application of this sort
will be relatively small, and the minerals added will be
more than sufficient to provide for a considerable
increase in crop. If the land is light and sandy,
nitrogen should be added, even though it has received
a good dressing of yard manure, ‘as these lands are
usually deficient in this element, and organic forms are
usually quite as useful as the soluble nitrate or
ammonia, since the seasonal conditions during the
period of growth are favorable for the rapid change of
the nitrogen in materials of good quality, like blood,
concentrated tankage, or cotton-seed meal, into nitrates.
The amounts of nitrogen needed would, under ordinary
conditions, be supplied by 100 pounds of high-grade
blood, or 200 pounds of cotton-seed meal. The nitro-
FERTILIZERS FOR CEREALS 201
gen may also be obtained by substituting tankage for
the superphosphate, though it is not so desirable a
practice.
In this matter of fertilizing, it must be remembered
that weeds appropriate plant-food quite as readily as
the corn, wherefore in order to obtain the best results
from the fertilizers added, clean cultivation should be
practiced.
Oats
For the oat crop that follows corn, and which makes
its best growth early in the season, before nitrification
is rapid, quickly available forms of nitrogen are very
desirable ; and inasmuch as the oats require an abun-
dance of phosphates, a fertilization with phosphoric
acid is also essential. Hence, fertilizers consisting of
mixtures of nitrate of soda and superphosphates have
proved of great value for this crop. If mixed at
home, they should be applied immediately after prepa-
ration, for a loss of nitrogen may result if the mix-
ture is allowed to stand for any length of time. An
application of 8 pounds of nitrogen and 18 of phos-
phorie acid, or 200 pounds per acre of a mixture of 50
pounds of nitrate of soda and 150 of acid phosphate,
has proved quite as profitable on medium soils as
heavier applications, mainly because the oat crop is
a less certain one than corn; besides, it frequently
suffers severe losses in harvesting, which increase the
risk from an expensive fertilization. The application
of potash is not so necessary if added in the fertil-
izer for corn, as suggested, except on light, sandy soils.
>
202 FERTILIZERS
Wheat
For the wheat crop following oats, the rest of the
farm manure on hand may be applied after plowing,
well harrowed into the surface soil, and a fertilizer ap-
plied which shall be rich in available phosphoric acid,
and which shall contain only a sufficient amount of
nitrogen in quickly available forms to insure a good
fall growth. When the land has been well fertilized
for previous crops, a dissolved animal bone super-
phosphate is an excellent fertilizer for wheat, because
containing the elements, phosphoric acid and nitrogen,
in good forms and proportions. If more nitrogen is
needed than is provided by 200 to 300 pounds of this
fertilizer in order to mature the crop, which is fre-
quently the case, particularly if the winter has been
severe, or if the land is light, it may be applied in the
spring, and preferably in the form of a nitrate, which
distributes readily, and is immediately available, ad-
vantages not possessed by other forms. At this period
of its growth, the crops need to make a rapid appro-
priation of nitrogenous food, though the conditions are
not yet favorable for the change of nitrogenous organic
compounds in the soil into the availabie nitrate. The
top-dressings should be made as soon as the crop has
been well started, and should range from 75 to 150
pounds per acre, according to the character of the
soil and previous fertilization. The better the natural
character of the soil and its treatment, the larger the
dressing that may be applied with possible profit,
though in no ease should it exceed the larger amount.
FERTILIZERS FOR CLOVER AND TIMOTHY 203
Clover
For the clover which follows the wheat, only the
minerals, phosphorie acid and potash, need be applied.
An inereased return is likely to follow such an
application, as the clover is not able to utilize to the
fullest extent the nitrogen from the air except when the
soil is supplied with an abundance of mineral food.
An appleation which will furnish 12 pounds of phos-
phorie acid and 25 pounds of potash per acre marks
the minimum dressing, and it may be applied with
advantage immediately after the wheat is harvested.
-Timothy
The timothy, the next crop in the rotation, is a
member of the grass family, and is especially benefited
by nitrogenous fertilization, and top-dressings in the
spring with nitrate of soda have proved of great value
on soils well supplied with minerals, though experienced
farmers have learned that better results are obtained if
the minerals are applied with the nitrate, thus in-
suring a better growth and development of plant. A
mixture made up of 150 pounds of nitrate of soda,
100 of acid phosphate and 50 of muriate of potash, at
the rate of 300 pounds per acre, is now used by many
successful hay growers. The application should be
made as soon as the crop has well started in the
spring.
The system of fertilization here outlined is not to be
advocated except under circumstances where it is not
204 FERTILIZERS
possible or practicable to supply such an abundance of
plant-food as will guarantee a maximum production, as
in “intensive” practice, in which the yield is measured
by climatic and seasonal rather than soil conditions,
but rather such additions as will return a profit and at
the same time tend toward the improvement of soil.
This system is economical in the use of nitrogen, the
most expensive element. It provides a_ sufficient
amount of available plant-food to insure a reasonable
increase in crop, and it is well adapted to lead the
farmer by easy steps from the “extensive” to the
“intensive” system of farming.
A Gain of Fertility by the Rotation System
Assuming that the inereased yield of corn is 20
bushels, with accompanying stalks, of wheat 10 bushels
per acre, of oats 15 bushels, of clover % ton, and of
timothy % ton, the amounts applied will be practically
sufficient to furnish all of the potash contained in this
increase, and more than sufficient to meet the demands
for phosphoric acid. That is, by this system, there has
been applied in the materials 30 pounds of nitrogen,
64 of phosphoric acid and 80 of potash. While, if
this increased crop was secured, the following amounts
would be required: 71 pounds of nitrogen, 31 of
phosphoric acid and 79 of potash. The considerable
amounts of plant-food contained in the yard manure,
and the gain from the roots and stubble of the clover,
serve to supply the balance of nitrogen required, and
to provide a store of unused residue for future crops.
NECESSITY OF AN EXCESS OF FOOD 205
The method, if adopted, would be more rational, and
likely to result in more satisfactory returns than the
one now generally practiced, namely, to purchase with-
out particular regard to the character of the materials
furnishing the constituents, or their proportions, and
to apply, on the average, even less per acre than is
here recommended. Assuming that 200 pounds per
acre of the average corn fertilizer, showing a composi-
tion of 2.5 per cent nitrogen, 8 of phosphoric acid and
5 of potash, were applied only to the crops corn, oats
and wheat, omitting both clover and timothy, there
would have been added 15 pounds of nitrogen, 48 of
phosphorie acid and 30 of potash, amounts of each too
small to provide for a large increase in crop, provided
all were needed.
The Necessity of Adding More Plant-food than is
Required by a Definite Increase in Crop
It may be asked, why add more of the constituents
than is necessary to provide for a definite increase in
crop? Assuming that the average yield of the land
is twenty bushels of wheat per acre, and the aim is
to secure thirty bushels, why not add the constituents
in the amounts and proportions necessary to provide
for this extra increased yield, rather than any
excess of these amounts? The answer is, that in
order that such a result may be accomplished, the
conditions would need to be absolutely perfect, so
that the plant would have at its command the amount
of food needed each day. If a period in the growth
206 FERTILIZERS
of the plant should be so wet or so dry as to prevent
the plants from acquiring the food necessary for their
continuous growth, there would be no opportunity for
them to gather food faster, when the better conditions
followed the unfavorable conditions, and thus to over-
come the ill effects of the period of partial starvation.
In other words, if there were only sufficient food to
supply the plant under normal conditions of season,
the plant, after a period of time during which there was
no growth, could not grow faster than it did before,
hence it could not eatch up in its growth and make a
full crop. Furthermore, the plan of applying only
that needed for the increase must necessarily assume
that the plant-food is in the best forms, and that the
physical conditions of soil are so perfect as to cause
it to absorb and retain all the food appled, and in
such a manner as to permit it to be readily obtained
by the plant. A further advantage is to enable the
clover plant in the rotation to fully exercise its power
of acquiring nitrogen from the air. Moreover, if
properly carried out, it fulfils the idea of successful
agriculture ; viz., the production of profitable crops,
while at the same time not reducing, but increasing,
the potential fertility of the soil.
The System Should Be Modified if no Farm Manures
are Used
In this rotation, if no manures are available, as
indicated, then the amounts and kinds of fertilizers
should be somewhat changed. For example, if it was
EXCLUSIVE USE OF FERTILIZERS 207
necessary to supply the corn crop with a sufficient
abundance of all the elements in artificial forms, then
the proportions of nitrogen should be somewhat greater
and the total amounts of the constituents applied to
the different crops considerably increased. For corn, a
mixture consisting of 20 pounds of nitrogen, 30 of
phosphorie acid and 50 of potash should be applied,
and if grown upon raw ground rather than upon sod,
it would be desirable to still further inerease the
nitrogen. The oats could be fertilized, as before rec-
ommended, while the wheat should have an increased
supply of both nitrogen and phosphoric acid,—double
the amounts recommended when used with manure,—
besides an addition of at least 10 pounds per acre of
potash. The fertilizing of the clover and timothy need
not be changed. If, in a rotation of this character,
barley were substituted for oats and rye for wheat, the
fertilization need not be materially changed, though the
rye possesses a slightly greater power of acquiring
phosphorie acid than wheat, and the nitrogenous top-
dressings may be omitted, unless the crop is grown
primarily for straw rather than for grain. The barley
is also less able to acquire its phosphoric acid than
the oats, and is especially benefited by nitrogen, though
eare should be exercised to regulate the amounts ap-
plied in order to prevent lodging, which affects both
the yield and quality of the grain. If in the rota-
tion the timothy hay is omitted, then the fertilization
for the corn may be reduced, as on good soils the
yard manure, together with the plant-food stored in
the surface in the clover sod, will furnish an abundance.
208 FERTILIZERS
FERTILIZERS FOR A SINGLE CROP GROWN
CONTINUOUSLY
When it is desirable to grow any one or all of
these crops continuously (and this practice may be
followed with advantage, particularly when a legumi-
nous catch-crop is seeded with the main crop, which
insures a continuous occupation of the land and also
provides vegetable matter and nitrogen), the fertiliza-
tion would naturally be somewhat different, and, as a
rule, would require more nearly even quantities of the
different constituents. For corn, a fertilizer supplying
20 pounds of nitrogen, 40 each of phosphoric acid and
potash, would provide for a liberal increase in the
yield from year to year. The nitrogen should prefera-
bly be in good organic forms, which would decay rap-
idly enough to supply the needed available nitrogen
during the growing season. The phosphoric acid may
be drawn partly from superphosphates and partly from
organic compounds, as ground bone and tankage, pro-
vided these latter may be secured at as low a price as
the superphosphate, and the potash applied in the
form of a muriate or kainit. Fertilizers may be applied
broadcast and well harrowed into the soil, or part may
be distributed in the row at time of planting.
If a catch crop were seeded to be used as green
manure, as, for example, crimson clover, the applica-
tion of nitrogen may be very materially reduced. This
practice has been followed with advantage in the middle
and southern states.
For continuous wheat growing, a fertilizer may be
FERTILIZERS FOR A CONTINUOUS CROP 209
used at time of seeding which supplies 10 pounds of
nitrogen, 40 of phosphoric acid and 20 of potash. A
small part of this nitrogen would better be in the form
of a nitrate, which will encourage a good top-growth
in the fall, as well as a deep root system; the phos-
phoric acid should be soluble, in order to supply the
immediate needs of the young plant, and the potash
in the form of a muriate. Such an application would
provide for a very considerable increase in crop, par-
ticularly if followed in the spring by a top-dressing of
100 pounds per acre of nitrate of soda.
The top-dressing with nitrate of soda is, however,
not always advisable. The chief objection to its use is
that it does not encourage, but frequently seems to
retard, the growth of clover, though its very great
advantage is that it encourages the deeper rooting of
the wheat and the more rapid growth of grasses. If
continuous cropping of wheat is practiced, clover
should be seeded with it, in order that the ground
may be constantly occupied, and thus prevent leaching,
as well as mechanical losses of fertility, and also to
supply vegetable matter containing nitrogen for the
succeeding crop. When a system thus outlined has
been continued for a few years, the nitrogen in the
fertilizer may be largely omitted.
The same considerations apply to rye as were in-
dicated for wheat. Oats are seldom grown as a
continuous crop, though if it should be desirable, a
fertilizer furnishing at least 20 pounds of nitrogen,
25 of phosphorie acid and 10 of potash would be a
good dressing, eare being taken that a large portion
N
210 FERTILIZERS
of the nitrogen exists as nitrate or as ammonia, in
order to stimulate and strengthen the early growth of
the plant. For the grass crop, or continuous mowing
land, a fertilizer rich in nitrogen and potash should be
applied. A good application in the spring may consist
of 25 pounds of nitrogen, 15 of phosphoric acid and
25 of potash, and immediately after the hay is har-
vested a further application of at least 20 pounds of
nitrogen and 30 each of phosphoric acid and potash
should be applied. The nitrogen in this case may
consist partly of organic forms, though the soluble
nitrogen is to be preferred as top-dressings where it
can be procured at such a price as to make it compara-
ble with other forms. The nitrogen of bone, tankage
and other slower-acting forms is excellent for the
grasses, though these should be preferably applied and
well worked into the soil previous to seeding. The
early spring application should consist largely of solu-
ble nitrogen, both to encourage a rapid appropriation
of this element by the plant early in the season, as
well as a deeper root-system, and consequently a
greater drought-resisting power, and also to provide the
elements necessary for the increased crop. The sum-
mer or later application stimulates and strengthens the
roots for the coming season. If an aftermath crop is
removed, or if it is pastured, a further application
may be made, which may consist largely of the mineral
elements. This fertilization of the hay crop will also
result in a richer product, for an abundant supply of
nitrogen encourages a larger proportion of leaf growth,
and consequently a smaller proportion of stem, contain-
FERTILIZERS FOR MEADOWS Pap ba A
ing the less valuable woody matter. Lands that are
well fertilized in this way, if properly seeded in the
first place, may make profitable mowing crops for a
long series of years, and good crops cannot be expected
unless liberal fertilization is practiced.
Fertilizers for Meadows
For meadows used as pastures, a more liberal
application of the mineral elements is recommended,
since an abundance of these encourage the growth of
the clovers, which make a richer herbage than the
grasses. Heavy nitrogenous fertilization is expensive,
and encourages the growth of the grasses rather than
the clovers. Pasturing, while less exhaustive than
- hay cropping, nevertheless results in the gradual
depletion of fertility, and an abundant growth of
rich pasturage can only be secured where there is an
abundant supply of available plant-food. Mixtures
made up of acid phosphate, ground bone and muriate
of potash in equal proportions, make very good
dressings, if applied in sufficient quantity, three hun-
dred to five hundred pounds per acre annually. The
ground bone is recommended because it decays
slowly, and thus furnishes a continuous supply of
nitrogen and of phosphoric acid. The application
should preferably be made both in spring and in late
summer, in order to secure a good growth, as well as
to encourage the introduction of the clovers. In any
system of continuous cropping, or in fact in any sys-
tem of rotation-cropping, in which an abundance of
212 FERTILIZERS
organic matter is introduced in the way of green
erops, or in decaying vegetable matter contained in
roots, the land should occasionally receive a dressing
of lime, both to supply that which the plants need,
as well as to correct possible acidity of soil.
WILL THIS SYSTEM of FERTILIZING PAY?
That fertilization will pay if carried out, as is
pointed out here, and upon lands not now producing
paying crops, depends, of course, very largely upon
the price of the crops, the cost of the materials, and
the method of farming practiced. At the prices which
have prevailed in the recent past, for both crops and
fertilizing materials, there is no doubt that this
reasonable fertilization, together with a good system
of practice in other respects,—that, is, good plowing
good harrowing, good drainage and good cultivation,
—will result in very satisfactory returns. In fact, it
has been shown by repeated experiments (see bulletins
and reports of New Jersey Experiment Station) that
the yields on land which is capable of producing an
average crop of 15 bushels of wheat per acre, 30 of
eorn and 30 of oats, may be more than doubled by
an abundant supply of fertilizing materials. Such an
increase results in an actual direct gain, as well as
in the saving of labor per unit of product, which is
accomplished when the larger crop is secured.
The main point in this whole matter of fertiliza-
tion is to understand that a fertilizer is a fertilizer
because of the kind and form of plant-food contained
WILL FERTILIZING PAY? 213
in it; and that its best action, other things being
equal, is accomplished when the soil possesses good
physical qualities, when the management is also
good, and when systematic methods are planned and
adopted. “Hit or miss” fertilization, even for these
crops, may pay, and doubtless, on the average does
pay as well as some other things that farmers do, but
does not pay as well as it might if better methods
were used.
CHAPTER XI
POTATOES, SWEET POTATOES, TOMATOES AND
SUGAR BEETS
These crops differ from the cereals and grasses in
that they are products of high commercial value, and
are less exhaustive of plant-food constituents per unit
of money value. As field crops they are usually grown
in a rotation, and constitute one at least of the chief
money crops. In sections near large markets these
erops are, with the exception of sugar beets, divided
into two classes, early and late, the early crop being
regarded as the most profitable; hence greater efforts
are made, both in the way of fertilization and of
management, to secure a large and early crop, than —
is the case with the late crop. For the early crop
the natural supply of plant-food in the soil is not a
prime consideration. In districts distant from markets,
the late crop is the only one grown to any extent, and
because it has the whole season for its growth, greater
dependence is placed upon the natural resources of the
soil. While, as already stated, these crops are not
regarded as exhaustive of plant-food elements in the
Same sense as the cereal crops are, because it fre-
quently happens that a bushel of potatoes, or of sweet
potatoes, or of tomatoes, will bring as much as a
bushel of corn, or sometimes as a bushel of wheat,
(214)
FERTILIZERS FOR POTATOES 215
yet the amount removed in the entire crop may be
quite as great as in the grain crop, because of the
much larger number of bushels grown per acre.
FERTILIZERS FOR POTATOES, EARLY CROP
It has been demonstrated, both by experiment and
practical experience, that good crops of early potatoes
require an abundance of plant-food, and that on soils
of good character a heavy fertilization is usually more
profitable than a medium or light application.
The plant-food removed by a fair crop— 200
bushels per acre of tubers—will, on the average,
consist of 27 pounds of nitrogen, 12 pounds of
phosphoric acid and 60 of potash. Even though
the increase from the application of fertilizers is less
than 100 bushels per acre, it is always advisable
to add plant-food in considerable excess of these
amounts: first, because the crop must be grown
quickly; and second, because a large part of its
growth must be made in the early season, before the
natural conditions are favorable for soil activities.
A study of the fertility composition of the potato
shows that of the three essential constituents, the
potash is contained in the greatest amount and the
nitrogen next, while the amount of phosphoric
acid contained in it is comparatively small. Most
fertilizer formulas for potatoes are, therefore, pre-
pared with the idea of furnishing a greater amount
of potash than of nitrogen or phosphorie acid. A
study recently made by the Geneva Experiment
216 FERTILIZERS
Station* shows that the formulas prepared to con-
tain the plant-food in nearly the proportions used
by the entire potato plant, excepting that the phos-
phorie acid is in considerable excess, were less useful
than those containing very different proportions
.of the constituents, and which were based upon the
experience of observing growers. That is, a formula
of the first class, furnishing —
RIOT; Cg chu ode the Bs 6% %
Available phosphoric acid. ........ 5 %
Potashes oi sh ey a Sa tee Ce eee 10 %
gave less satisfactory returns for the same amount
applied than one furnishing —
Mrmr sos patie FT) eh tees Saheet 4%
Available phosphoric acid. ........ 8 %
Pipher Sk aah | nd See Sins es eee 10 %
This latter formula is very generally used in sections
where early potatoes are an important crop.
The Time and Method of Application
These are matters of considerable importance.
It has been urged, particularly by German experi-
menters, that the potash salts, when used in such
excess as seems desirable, should be applied more
largely to the crop preceding, rather than directly to
the potato crop. This method has not been adopted
in this country to any extent, and it is believed that
* Bulletin No. 137, N. Y. State Exp. Sta.
THE AMOUNT OF FERTILIZER OG
our climatic conditions are such as to cause a very
general distribution of the salts throughout the soil,
if applied, in part at least, just before planting and
thoroughly distributed by cultivation. At any rate,
very satisfactory returns are secured from the direct
application to the crop of fertilizers of this composi-°
tion. In reference to the method of application, while
very good results are secured from the application of
the fertilizers directly in the row, this is to some
extent influenced by the character of the soil. Where
the soil is somewhat heavy, and the circulation of
water is not perfectly free, it is less desirable than
where the soils are open and porous, and free circu-
lation is not impeded; though where the amounts
applied are considerable, it is recommended that at
‘least one-half of the fertilizer should be applied
broadcast and worked into the soil, and the remainder
placed in the row at the time of planting. Naturally,
when the soils are poor, a concentration of the con-
stituents is more desirable than when the surround-
ing soil possesses reasonably abundant supplies of
available food.
The Amount to be Applied
As already stated, the amount of the different con-
stituents to be applied should be in considerable excess
of that required by the actual increase in crop, ‘both
for the reasons already given, and because it is
desirable in crops of this sort to insure a continuous
and abundant feeding of the plant. Where “intensive”
918 FERTILIZERS
practice is general, the amounts applied very frequently
reach a ton per acre of the high-grade fertilizer
already mentioned, though the necessity for so large
an application as this has been questioned, particularly
if it is expected to give rise to a profitable return in
the crop to which the application is made, and though
it can be readily seen that if conditions should not be
favorable the larger amounts would be preferable. The
result of investigations of this point by the Geneva
Experiment Station* showed that an addition of fer-
tilizers above 1,000 pounds per acre, or 40 pounds of
nitrogen, 80 of phosphoric acid and 100 of potash,
was not as profitable as 1,000 pounds. It must be
remembered, however, that these experiments were
conducted upon light soils, and on these entire de-
pendence must be placed upon added plant-food.
In the best potato sections of New Jersey, the
application of a fertilizer of this composition ranges
from 1,000 to 2,000 pounds per acre, while the majority
of the growers use the smaller rather than the greater
quantity. Many use the larger, and are of the opinion
that it is a profitable practice, because of the greater
certainty of securing a good potato crop, and because
the unused residue provides for large yields of the
subsequent crop without further applications. The
growers of potatoes in the vicinity of Norfolk, as
well as farther south, also find it profitable to be
generous in the use of fertilizer for this as well as
for other crops of high commercial value,
*Bulletins 93, 112, 137. N. Y. State Exp. Sta.
FERTILIZERS SHOULD BE AVAILABLE 919
Form of the Constituents
In the growing of potatoes, sulfate of potash is
generally recommended in preference to the muriate,
owing to the supposedly deleterious effect on the
quality of the tubers resulting from the large quantities
of chlorids contained in the muriate, though the dif-
ferent forms, when properly applied, do not seem to
materially influence the yield. That is, if muriate or
kainit is applied previous to the planting of potatoes,
the deleterious chlorids may be washed from the soil.
There is no doubt that the sulfate improves the ap-
pearance of the potatoes, making them more clean and
uniform in size, though experiments that have been
conducted do not show a material difference in the
‘chemical composition of the tubers grown with any
of the forms. The tendency on the part of the mu-
riate seems to be to diminish the amount of dry
matter, and inasmuch as the dry matter is mostly
starch, the latter is thereby slightly reduced, though it
has not yet been demonstrated that the good quality of
the potatoes is measured by the content of starch.*
In reference to the form of nitrogen, both theoret-
ical considerations and the experience of growers con-
firm the belief that for the early crop, a portion of
the nitrogen should exist in the form of nitrate or
ammonia and the remainder in quickly available
organic forms, although no definite experiments have
been conducted to determine this point, nor the one
* Bulletin No. 137, N. Y. State (Geneva) Exp. Sta. Bulletin No. 80, N. J.
Exp. Sta.
990 FERTILIZERS
as to whether all of the nitrogen in the form of
nitrate should be applied at the time of planting. A
top-dressing after the potatoes have come up is a very
desirable method of practice on light soils which have
been liberally supplied with the minerals.
On good potato soils, therefore, a good fertiliza-
tion would consist of 800 pounds per acre, as a mini-
mum, of a mixture containing:
Nitro @eN ate, a 2 ek oe 2 ae eee 3to 4%
PROSPHOTIC: BEM. 5 5. 6) Sao k kg eee 6to 8%
Potente oF SS ars 2s een tebe 8 to 10 %
The nitrogen is to be in quickly available forms;
the phosphoric acid, also, is to be available, and the
potash to be derived from sulfate, particularly if fine
quality of crop, as indicated by appearance, is desired.
If only yield is considered, the muriate is quite as
serviceable.
LATE POTATOES
For late potatoes, the considerations in reference
to the form of the constituents and the amount of the
application, as suggested for early potatoes, do not
always hold good, since in many eases the crop is able
to secure a larger proportion of its plant-food from
soil sources,—due, first, to the longer period of growth
of the plant, and second, to the fact that the crop is
usually grown upon soils naturally richer in the
plant-food elements, though the proportion of pot-
ash, as in the formulas already indicated, should be
relatively large. The nitrogen may be reduced, and
FERTILIZERS FOR SWEET POTATOES yw
the form of nitrogen may be derived largely from
organic sources. Good formulas for late potatoes
may consist of —
PIR MIIE NA os i oe Fe nies (5) NT old 2 a 214 %
UOTE WEI spr EE Paes 6 %
WECM or co a EE han iw oe ~ oat 8%
and the application may be from 600 to 800 pounds
per acre.
Where potatoes are grown in rotations with the
cereal crops mentioned in Chapter X, the unused
residue from the rather heavy application of fertil-
izers to the potato crop is depended upon to very
materially aid the growth of these, thus reducing the
outlay for fertilizer for crops of a low commercial
value. This practice is advantageous, though the
prime object should be to feed the crop rather than
the soil—that is, apply the fertilizer with the idea of
securing a profit from it in the potato crop, rather
than a possible profit in subsequent crops.
SWEET POTATOES
In the growing of sweet potatoes, the quality of
the product is more important than in the ease of the
white potato. The northern markets distinctly recog-
nize quality in this crop, and it is measured by size,
shape, and results in cooking. The potato that brings
the best price in the different markets is small, about
the size of a white potato; in shape round, rather
than oblong, and is dry and mealy when cooked.
pp FERTILIZERS
This characteristic of the crop is influenced both
by the character of the soil and of the manures and
fertilizers applied. The soils best adapted are dry,
sandy loams, and the most useful fertilizers are those
which contain an abundance of minerals,—phosphorie
acid and potash,—and not too large supplies of quickly
available nitrogen. It is also true that the yields of
sweet potatoes of this character are not as large as
those that may be obtained when quality is not a
prime consideration, and which are grown for the
general market.
Fertilizer Constituents Contained in an Average Crop
This crop is very similar to the white potato in
regard to food required. Two hundred bushels of
sweet potatoes, not including vines, contain, on the
average, 30 pounds of nitrogen, 10 of phosphoric acid
and 45 of potash; and since the yield of the general
erop is larger on the average than one of white
potatoes, a liberal supply of the minerals must in
all cases be provided. The studies made of this crop
have not yet established the best proportions of the
constituents in fertilizers, though such experiments
as have been conducted show that those that contain
a very considerable excess of potash over the other
elements are preferable. While nitrogen is needed,
too much, particularly in soluble forms, seems to
encourage too large a growth of vine, which con-
tributes to yield, but at the expense of quality, which
is a very important consideration. The best growers
PROFITABLE FERTILIZATION 993
use fertilizers containing a small percentage of nitro-
gen and a high percentage of phosphoric acid and
potash. Applications that furnish 20 pounds of nitro-
gen, 50 of phosphoric acid and 80 of potash per acre
have given excellent results in regions in New Jersey
in which market quality up to a certain point is quite
as important as increase in yield, though, of course,
yield is also considered. Any excess of nitrogen over
this amount seems to contribute toward a larger,
rather oblong, rooty growth of tuber, and to injure
cooking quality. In growing crops for the general
market, however, larger applications of nitrogen are
demanded, and experiments have shown that organic
forms are preferable to soluble forms, though the
climate and season largely influence this point. In
northern sections, and in cold seasons, the soluble
forms are more useful than in the warmer climate
and longer seasons of the South.
There is no question, however, that commercial
fertilizers can be depended upon to produce maximum
crops of sweet potatoes, and at much smaller cost
than with yard manure.* Results reported by the
Georgia Experiment Stationt indicate the following
formula as an_ excellent one for sweet potatoes,
though, as there stated, “the amounts that can be
used vary considerably, depending upon the character
of the soil—the richer the land in humus, the greater
the quantity that can be safely used.” “Thin soils
will, of course, only stand very moderate manuring,
—_— ——_
* Bulletin P, New Jersey Exp. Sta.
7 Bulletin No. 25, Georgia Exp. Sta.
224 FERTILIZERS
and necessarily produce a very small yield.” The
formula consists of —
GIG TORDHALO 2 OS ee ce ee ee ee 320 Ibs.
Catt@n-ssea moal =... 2... eee 360.
aa Fr. i te eee 040 «SS
This formula will furnish about 25 pounds of nitro-
gen, 50 of phosphoric acid and 80 of potash, and,
according to the bulletin, will produce a yield of
potatoes of from 200 to 400 bushels per acre, depend-
ing upon the season and variety of potatoes planted.
Experiments at the Georgia Station also show that
organic nitrogen (cotton-seed meal) is preferable to
nitrate of soda as a source of nitrogen.
In making mixtures which furnish these propor-
tions of plant-food, other nitrogenous organic ma-
terials, furnishing an equivalent of nitrogen,—as blood
or concentrated tankage,—may be substituted for the
eotton-seed meal, if they can be purchased quite as
cheaply; and muriate of potash, furnishing an equiva-
lent of potash, may be substituted for the kainit, if
it can be more readily obtained.
As already stated, however, this fertilizer is too
rich in nitrogen for the production of the best quality
of potatoes, as for example “Vineland Sweets,” which
command the highest prices in northern markets. The
erowers in that district use a fertilizer richer in the
minerals; one containing —
Nitros. 6 i a ele eee eee 3%
PhOpphorie-acid.s 6.5" Sa eee 7%
Piao oe eS See ere 12%
APPLICATION OF FERTILIZERS hag
is very generally used, though reasonably heavy
dressings of this are often further supplemented
by applications of from 200 to 3800 pounds of acid
phosphate and 100 to 150 pounds of muriate of
potash per acre.
The Application of the Fertilizers
Owing to the fact that the sweet potato is grown
from plants or slips, rather than from seed, and the
fact that the best quality of potatoes is produced upon
rather light, sandy land, it is desirable that the fer-
tilizer should be applied some time before the putting
out of the plants. The practice on this light land is
to apply the fertilizer when making up the hills, which
~usually occurs from two to three weeks before the plants
are set. “That is, in making up the hills, the soil is
ridged, and during the preparation of the ridge the
fertilizer may be distributed in it and well mixed with
the soil. Where the land contains more clay and
humus it is frequently advocated that the potash
manures be applied broadcast the previous year, and
only the nitrogenous fertilizer and superphosphate be
applied immediately to the plant. On soils of this
latter character, this is doubtless the best system. If
kainit,—which has been found to be preferable to mu-
riate in the Georgia experiments referred to,—is used
as the source of potash, it is very necessary that it be
well mixed with the soil before setting out the plants.
Heavy applications of this salt in the spring proved
injurious in the experiments conducted at the New
O
996 FERTILIZERS
Jersey Station.* The effect of fertilizers upon the
chemical composition of the tuber was chiefly to reduce
dry matter, and not apparently to affect edible quality,
though the experiments were carried out upon the
general crop rather than upon those grown for high
quality.
TOMATOES
Tomatoes are largely grown as a field crop, and
the object of their growth, whether for the early
market or for the canneries, is a factor that must be
considered in the adoption of systems of fertilization.
Field Experiments with Fertilizers for Tomatoes
The impression is very prevalent among growers
that the tomato does not require heavy manuring.
Studies made at a number of experiment stationst
show, however, that the tomato is a plant that quickly
and profitably responds to the use of manures or ferti-
lizers, and that the maturity and yield are very largely
influenced by the method of manuring and fertilizing.
Experiments were conducted by the New Jersey Station
upon three farms located in different parts of the state,
and during four seasons, the object of which was to
test the effect on maturity and yield of the early crop
* Bulletin P, New Jersey Experiment Station.
+ Bulletins Nos. 21 and 32, Cornell Experiment Station (Ithaca). Bulletin
No. 17, Georgia Experiment Station. Annual Report for 1891, Maryland Experi-
ment Station. Bulletin No. 11, Virginia Experiment Station. Bulletins Nos. 63,
79 and O, and Report for 1892, New Jersey Experiment Station.
THE NEW JERSEY EXPERIMENTS ae
of the use of nitrate of soda in different quantities
and at different times, both with and without the ad-
dition of the mineral elements, phosphoric acid and
potash, and to make a comparison of these with barn-
yard manure. The results showed:
First. That nitrate of soda was one of the best
nitrogenous fertilizers for this crop, and that its use
in small quantities (160 pounds per acre), or in large
quantities (320 pounds per acre) in two applications,
increased the yield materially, but not at the expense
of maturity, and that this was equally true when used
alone and when used in connection with phosphoric
acid and potash.
Second. That nitrate of soda, when used in large
quantities (320 pounds per acre) in one application, in
' the presence of a sufficient excess of phosphoric acid
and potash, did increase the yield, but at the expense
of maturity.
Third. That when properly used, nitrate of soda
was a profitable fertilizer for the crop.
It was shown, furthermore, that nitrate of soda was
superior to both barnyard manure and mineral ferti-
lizers alone, and on the whole, was but slightly less
effective than the complete fertilizers.
Fertilizers for the Early Crop for Different
Conditions of Soil
These results have been practically confirmed both
by the experiments of the stations referred to, and
also in actual practice on soils similar in character ;
II8 FERTILIZERS
namely, those which were well adapted for the early
tomato — light, well-drained sandy loams—and which
had been previously well manured for crops entering
the rotation. The results do not apply in the case of
very poor soils, or upon heavy elay soils, which are
not adapted for the early crop.
The statement that it pays to fertilize early toma-
toes, and that nitrate of soda is one of the best ferti-
lizers for the crop, must, therefore, be accompanied by
statements regarding the condition of soil and the
purpose of growth. With the conditions clearly under-
stood, a scheme of fertilization for early tomatoes may
be outlined which, when the conditions are observed,
will be likely to give much better results than methods
of fertilization which do not take into consideration
the habits of the plant and the special object of its
erowth.
For example, on soils which have been well sup-
plied with the mineral elements, phosphoric acid and
potash, by previous manuring or fertilizing, a ferti-
lizer very rich in nitrogen derived from nitrate of
soda, or nitrate of soda alone, should be used; the
application at the time of setting the plant to be
equivalent in nitrogen to from 80 to 100 pounds of
nitrate of soda, with a second application of an equiv-
alent amount made from three to four weeks later.
A single application of the amount here suggested at
the time of setting the plants would, perhaps, under
good seasonal conditions give results quite as good,
though the heavier application of nitrate at one time
may result, in certain cases, in the loss of nitrogen
FERTILIZATION OF THE EARLY CROP II9
by leaching, since it is an extremely soluble salt. In
this ease a deficiency of food would result, and thus
prevent the normal development of both plant and
fruit.
On soils which possess only good mechanical con-
dition, and are very poor in plant-food, a_ heavier
application of both nitrogen and the mineral elements
will be required, in which case the following fertiliza-
tion is recommended :
Previous to setting the plants, or at the time they
are set, apply 50 pounds per acre of phosphorie acid,
preferably derived from superphosphate, and 100
pounds of potash, derived from muriate, and thor-
oughly harrow or cultivate into the soil; and at
the time of setting apply around the hill 100 to 150
pounds per acre of nitrate of soda. Three to four
weeks later, make another application of from 100 to
150 pounds per acre of nitrate of soda. Owing to the
small bulk of nitrate, it should be mixed with dry
soil or sawdust, in order to insure even distribution.
The only precaution to be observed is to prevent. its
immediate contact with the plant roots. If these
methods are practiced, the plant secures its nitrogen
in an immediately available form at a time when it
is needed,—when it is set in the field. There is
thus no delay in growth, and because of the presence
of an abundance of the mineral elements no ex-
cessive growth of vine is encouraged by the use of
the nitrate, as would be the case were the mineral
elements absent. Inasmuch as the nitrogen is ap-
plied close to the plant, it is within the immediate
930 FERTILIZERS
reach of its roots; and because it is all in an im-
mediately available form, which is used up rapidly,
the tendency to late plant growth, which would be
caused by a continuous supply of nitrogen, is not en-.
couraged, and a normal and rapid growth and de-
velopment of fruit results.
It is not stated that by this method of fertilization
maturity is increased in the sense that the date of the
first picking is earlier, but that a larger number of
fruits is picked earlier. It was not shown in any of
the experiments that the date of picking was made
earlier by virtue of the nitrate, for, in fact, the
earliest tomatoes were picked upon land where the
minerals only had been applied. Here the yield was
not satisfactory, but where the nitrate was applied,
because of the larger crop, a larger proportion of
early tomatoes was secured. It is obvious that, in-
asmuch as the price of the fruit rapidly declines as
the season advanees, receipts from the proportionately
larger quantity of early fruit will be materially
increased.
The Use of Fertilizers with Yard Manures
When it is desirable to use yard manures with fer-
tilizers for tomatoes, because of the abundance and
cheapness of the former,they should be applied broad-
cast, and the nitrate applied at the time of planting, as
already described, rather than both together in the hill.
The tendency in the latter case will be to cause a loss
of nitrogen from the nitrate, depending upon the
FERTILIZATION OF THE LATE CROP 931
amount of organic matter in the manures. That is,
experiments and experience have shown that under
these circumstances more or less of the nitrogen in the
nitrate may be lost.
In the use of yard manures for early tomatoes, the
application of excessive quantities should be avoided,
as they are virtually nitrogenous manures, which,
because of their organic character, feed the plant in
proportion to their rate of decay. Hence, the presence
of large quantities will encourage not only an undue
growth of plant, but a late growth as well. The
mineral fertilizers, as acid phosphate and muriate of
potash, can be used with the yard manures with perfect
- safety, in fact, with great advantage, because supple-
menting their proportionate lack of the mineral con-
stituents. It is also desirable, where it is the practice
to use manure, particularly if it is coarse, to spread it
during the winter, in order that the soluble portions
may become thoroughly distributed throughout the
soil. As soon as the land is ready to work in the
spring, it should again be plowed shallow and then
deeply tilled, in order both to thoroughly warm up the
soil, and to incorporate with it coarser portions of the
manure.
Fertilizers for Late Tomatoes
In manuring and fertilizing for the late crop, the
character of the crop and the season of its growth
should be remembered. In the first place, the plants
for this crop are not put in the soil until summer, when
the conditions are most favorable for the rapid change
939 FERTILIZERS
of organic forms of nitrogen into nitrates. Thus, if
the soil has been manured or is naturally rich in vege-
table matter, the additional application of nitrogen in
immediately available forms is not so important. In
the second place, the object of the growth is not early
maturity, but the largest yield of matured fruit; hence
it is more desirable to grow a larger plant than in the
ease of the early tomatoes. The fertilization should,
therefore, be such as to furnish an abundance of all the
elements of plant-food; and, inasmuch as the tomato
belongs to the potash-consuming eclass.of plants, any
fertilization should be particularly rich in this element.
It is not to be understood, however, that it is not
necessary to apply nitrogen, for frequently soils are
used that are either not well adapted for the plant or
are poor, not having been previously well supplied with
vegetable matter containing nitrogen. On such soils,
additional applications are very important, and nitrate
of soda is one of the best forms to use, as it is absorbed
freely by the roots, encouraging an early and vigor-
ous growth of plant and a normal development of
fruit. Slow-acting organic forms of nitrogen, on the
other hand, frequently begin to feed the plant and
cause its rapid growth when the energies should be
concentrated in the growth and maturity of fruit.
Fertilizers that have proved very excellent are those
which contain a relatively smaller amount of nitrogen
than is required for early tomatoes, and are richer in
phosphorie acid and potash.
A study of the composition of both the fruit and
vine of the tomato will serve to guide us in ths
COMPOSITION OF FRUIT AND VINE 933
respect, though the amounts and proportions of food
removed by any crop are not absolute guides, inas-
much as the soil may furnish more of one constituent
than another, and because the plant may have the
power of acquiring certain of its constituents more
readily than others. The analyses of the fruit and
vines of tomatoes show that one ton contains:
ae Metied: Sh Acid sil eg
Warrine ese 3.20 1.00 5.40
Vines (green). . . 6.40 1.40 10.00
Ten tons of the fruit, with the accompanying
vines, which would probably reach four tons, would
contain 57 pounds of nitrogen, 16 of phosphoric acid
and 94 of potash. On a good soil, therefore, which
-without manure would produce five or six tons,
there should be added a_ sufficient excess of the
constituents to provide for a maximum production,
and the materials should be relatively richer in nitro-
gen and potash than in phosphoric acid. A mixed
fertilizer composed of :
ieee ae ei 8 elle ie S88 400 lbs.
rn Te on a etn ahs TOR. <**
UE NOMBISEO co ooo. es cay Sc er bn ee 400 ‘
Mariate. Ge DOME . 6 eos me eae wes 500 ‘*
would contain, approximately, 95 pounds of nitrogen,
144 of phosphoric acid and 250 of potash in each ton.
An application of 500 pounds per acre of this mixture
would furnish half as much nitrogen as is contained
in a crop of ten tons, nearly as much immediately
available phosphoric acid, and two-thirds as much
234 FERTILIZERS
potash. Hence a dressing containing the amounts,
kinds and proportions of plant-food here shown would
be regarded as very desirable, since one-half of
the nitrogen is in the form of a nitrate, which would
contribute to the immediate growth of the plant. The
amount of soluble and available phosphoric acid is
sufficient to satisfy the needs of the crop throughout
its entire growth, and such an abundance of potash
as to contribute to the normal development of both
plant and fruit. Formulas of this character have
been used with good results, though the large pro-
portion of salts sometimes make mixtures of this sort
too moist to handle well, in which ease a part of the
potash, or even of the nitrate, may be applied
separately with advantage. On poorer soils, the arti-
ficial supply of plant-food should be proportionately
greater, or sufficient to provide for the entire needs
of a fair-sized crop, since as a rule the relative power
of the plant to acquire food is somewhat slighter on
poor soils than on good soils; or, stated in another
way, the results from the use of fertilizers are pro-
portionately better upon soils in good condition than
upon those not well cared for. A good formula for
these may consist of:
Witrate Gf Bodsiye 2320.45 eee eee 500 Ibs.
Bone tanked) <> be) sh hy oa 500°
Acid phiaphnte” .-1 es. aoud ers et oe 400 ‘S
Murinte of potash. .s 0. <2 0-76 ee eee 600 ‘‘
One ton of this mixture would furnish, approximately,
105 pounds of nitrogen, 120 of phosphoric acid and
300 of potash. The application of 1,000 pounds,
NEED FOR NITROGEN REDUCED Ja5
therefore, would furnish the food in sufficient abun-
dance and in good proportions to meet the demands
of a fair crop.
The advantage of using so large a proportion of
nitrogen in the form of nitrate of soda in this case
is, that it is immediately available, inducing the im-
mediate and rapid growth of plant, and preventing a
too late growth by furnishing a minimum of organic
nitrogen, which would become available late in the
season. The cost of the fertilizer suggested in these
eases is high, and the necessity of so expensive a
dressing could be materially reduced by decreasing
the need for nitrogen, particularly in organic forms,
which may be accomplished by sowing crimson clo-
ver with or after the previous crop of, say, corn or
tomatoes. If weather conditions are favorable, crim-
son clover may be sown in the tomato fields in
August, after cultivation has ceased, or at the last
cultivation, and a crop of clover grown which will
provide nitrogen for the next year’s crop. This
method is now practiced with advantage by many
growers. The late crop, like potatoes and sweet pota-
toes, is usually grown in rotations in which it is the
chief money crop; hence the unused residue from fer-
tilizers applied in large amounts, as here indicated,
contributes largely to the economical growth of sub-
sequent crops.
SUGAR BEETS
The purpose in the growth of sugar beets is to
obtain the largest total yield of sugar per acre; and
936 FERTILIZERS
inasmuch as the sugar content of the beet, as well as
its ‘right growth and development, is very largely
influenced by the character of the fertilization, this
matter becomes of very considerable importance, in
view of the promising development of the sugar beet
industry in this country. Thus far, information con-
cerning the use of fertilizers is derived largely from the
results obtained in other countries, where it has been
a prominent crop, and where great attention has been
paid to this factor in its production.
The Demands of the Crop for Plant-food
The sugar beet draws heavily upon the soil for the
nitrogen and potash constituents. A minimum yield of
10 tons of topped beets contains 44 pounds of nitrogen,
20 of phosphoric acid and 96 of potash. On medium
loamy soils, which by their character are well adapted
for the growth of the sugar beet, heavy fertilization
with potash, however, has not been found to be de-
sirable; while on light soils, which are also well adapted
for the crop, liberal manuring with potash becomes
absolutely necessary.
As in this erop, the object of the growth is to se-
cure not primarily beets, but sugar, and since the sugar
formation is not perfected until the absorption of the
necessary food from the soil has been in large part
completed, any fertilization which promotes a too rapid
or too long continued growth has a tendency to reduce
the percentage of sugar; and inasmuch as the matu-
ration takes place largely in the months of early fall,
FERTILIZATION OF SUGAR BEETS 237
the growth must be forced early in the season. That
is, it is essential that a large and rapid leaf growth be
made early, in order that the food from the air may be
acquired. It has been demonstrated that for this early
and rapid growth of the beet, phosphoric acid is one
of the most essential constituents, which explains the
need for phosphoric acid in larger proportion than is
indicated by the composition of the beet. The crop
requires a considerably greater supply of phosphoric
acid at this stage of its growth than other farm crops
which are quite as exhaustive, and it is also evident
that in order that the crop may obtain the phosphoric
_acid at this period, it must be soluble and immediately
available; hence the larger portion of this element
applied should be derived from superphosphates. In
the matter of fertilization with nitrogen, the object of
the growth must also be kept in view. An application
which would encourage steady and continuous growth,
rather than an early and rapid growth, while contrib-
uting to a large yield, causes a reduction in the sugar
content of the beet. Hence it is strongly urged by
those who are in a position to give sound advice, that
the early nitrogen fertilization should consist of the
quickly available forms, nitrate or ammonia, and that
the organic or slower-acting forms should not be
applied in such excess as to encourage a late growth.
Hence it is, that upon medium and light lands the use
of commercial fertilizers has proved of greater service
in the growing of this crop than the exclusive use of
yard manure, and in such quantities as to supply the
entire needs of the plant. In the use of fertilizer, not
938 FERTILIZERS
only the total supply of the constituents, but their
form, may be regulated to the needs under different
conditions, thus permitting a full feeding of the plant,
and at a time most suitable to accomplish the object
in view,— advantages which are not possessed by the
natural manures.
A fertilization which would meet the needs both in
respect to quantity and kind of fertilizers, may be as
follows:
On good soils, the application or a fertilizer con-
taining from 40 to 50 pounds of nitrogen, from 50 to
60 of phosphoric acid and from 40 to 50 of potash,
would be sufficient to meet the demands of the plant.
The nitrogen supplied should be derived largely from
nitrates or ammonia, or both, and the phosphoric acid
from a superphosphate, while the potash may be de-
rived from sulfate or muriate of potash. The former
is preferable if applied during the spring preceding
the planting of the beets. While it is frequently
desirable, for convenience and economy of labor in
applying, that the fertilizer should be mixed, in order
to prevent any waste of soluble nitrogen, it should be
applied in fractional dressings. For example, a mix-
ture of 250 to 300 pounds of nitrate of soda (or, the
nitrogen may be derived partly from nitrate and partly
from ammonia), 400 to 500 pounds superphosphate,
and 80 to 100 of muriate or high-grade sulfate of
potash, should be applied in two or three dressings.
A part only should be applied previous to sowing, for
both the nitrate and the potash salts have a depress-
ing effect upon germination. They are preferably ap-
ADVANTAGES OF DEEP CULTIVATION 939
plied, say, one-third of the mixture as soon as the
plants have come up, another third immediately after
or before the first cultivation, and the remainder
immediately after or before the second cultivation.
The application of the fertilizers in these forms and
at the times indicated insures the rapid and early
growth and development of the plant; and by reason
of the solubility of the nitrates and ammonia salts, a
late feeding of the plant with nitrogen is obviated.
On light or medium soils, the amount of plant-
food should be increased by at least one-third, though
fractional applications should be made as _ previously
recommended. On soils rich in vegetable matter, a
part of the nitrogen may be omitted, though the phos-
phorie acid should not be reduced.
The Influence of Previous Deep Cultivation of Soil
Another point to observe in the growing of beets
for sugar,—and it also has an immediate bearing upon
fertilization,—is the character of the previous cultiva-
tion. If the soils have not been deeply and well eulti-
vated, so large a dressing as is here recommended
would be likely to be deleterious, as with a shallow
and poorly prepared soil plants would have less op-
portunity to penetrate deeply, and thus too great a
growth above the surface of the ground would be
encouraged, with a consequent lowering of sugar con-
tent as well as yield.
The best practice in our country will have to be
developed by the experience of our own growers,
940 FERTILIZERS
though in the absence of such experience, the recom-
mendations here made may be relied upon. In many
of the sections of this country in which the soils and
climate are well adapted for the sugar beet industry,
the needs as yet are quite as much for improved
methods of cultivation as for added fertility. They
have not been exhausted of their essential elements
of fertility.
An epitome of the soil conditions for sugar beet
eulture will be found in the second edition of
Roberts’ “Fertility of the Land,” p. 400.
CHAPTER XII
GREEN FORAGE CROPS
A LARGE number of crops is included in this elass.
In dairy districts they are grown for summer feeding,
mainly to supplement or to entirely substitute pas-
turage, as well as to provide a succulent ration of
roughage in winter. Any crop which grows quickly,
is palatable, and makes a reasonably large yield, is
adapted for the purpose. For convenience of study,
these crops may be further classified into three
groups :
1. Cereals and grasses. 2. Clovers and _ other
legumes. 3. Roots and tubers.
In the case of those included in the first group, the
purpose or object is to obtain as large a growth of
leaf and stem as possible. Thus the character of the
fertilization may differ from that recommended when
the same crops are grown for the primary purpose of
obtaining the. largest yield of seed or grain. These
erops, too, may in all cases be considered as only well
adapted for the “intensive” system of practice—that
is, when the management is such as to encourage the
largest yield possible per unit of area under the ex-
isting conditions of climate and season. ‘I'he natural
fertility of the soil thus becomes a less important
factor; indeed it cannot be relied upon altogether, as
P (241)
OAS FERTILIZERS
the largest yield of succulent food is dependent upon
a rapid and continuous growth, and hence the supply
of plant-food must be relatively much greater than is
the ease when the cereals are grown for their seed.
That is, forage crops, because suecculence is a factor
influencing quality, must, as a rule, be grown quickly,
and in order that large yields may be obtained in a
short period of time a relatively greater abundance of
plant-food must be at their disposal than when the
growth is distributed through a longer period. Be-
sides, larger amounts of all of the food constituents
are required for the production of the same amount of
dry matter per acre than when grown for the mature
crop, because the dry matter of the mature crop is
richer in the constituents derived from the air and
poorer in those derived from the soil, than the dry
matter of the immature crop.
Maize (Corn) Forage
A valuable forage crop of the first group is maize
(Indian corn), because it grows quickly, is well adapted
for a wide variety of soils and climates, is extremely
palatable, and is capable of producing large yields.
The fertilization which has been recommended for the
field crop is less desirable than one which furnishes a
greater proportion of nitrogen, because of the greater
need of this element, and because it encourages a
larger leaf and stalk growth; and the greater the pro-
portion of these in a corn crop the richer will be the
dry matter in the important compound protein, and
FERTILIZERS FOR CORN FORAGE 943
nitrogen is the basic element in this group of nu-
trients.
When the crop is grown on good land on clover
sod, which has been liberally manured, the fertilizers
applied should be particularly rich in the mineral
elements, phosphoric acid and potash. An application
of 500 pounds of a mixture containing—
LES 2 ce a I, ecees eet OOS aaa ae em ae 2%
Available phosphoric acid ......... 6 %
RMR Crs Ct eta eG hae eae Sa. ga: bs. te HOG 8 %
would provide an abundance of food, even should
unfavorable conditions intervene, but when grown on
light, unmanured soil without sod, a larger amount of
nitrogen should be used in connection with the min-
erals. An application of 25 pounds of nitrogen, 35 of
phosphoric acid and 50 of potash is as small a fer-
tilization as should be recommended on soils of this
character, since a yield of 10 tons per acre, containing
25 per cent of dry matter— which is only a fair crop
—would remove 60 pounds of nitrogen, 25 of phosphoric
acid and 70 of potash. Hence, very large increases in
yield could not be expected from smaller dressings,
unless conditions were absolutely favorable throughout
the entire period of growth. The nitrogen, as in the
ease of field corn, may be derived from organic sources,
as the season of growth is the same—the summer—which
is the most favorable for encouraging a rapid change
of the organic nitrogen into the soluble nitrates. The
phosphoric acid should be in large part derived from
superphosphates, though since the season of growth
944 FERTILIZERS
and the character of the crop and of its cultivation are
conditions all of which favor a rapid change of in-
soluble into available forms, a portion may be sup-
plied by ground bone or tankage. The potash may be
kainit or muriate, though if kainit is used, it should
be broadeasted and well worked into the soil before
planting.
Silage Corn
Corn grown for the silo, while distinctly a forage
crop, is, in its management, very similar to the field
erop, and is not planted so thickly as to prevent the
formation of ears. The object in its growth is, how-
ever, to obtain a large yield of dry matter, somewhat
richer in nitrogenous substance and poorer in starch
and woody fiber than field corn. Hence the fertilizers
for the crop on medium soils should be richer in
nitrogen than for the field corn, where the primary
object is the grain, and where heavy fertilization with
nitrogen would encourage a disproportionate stalk
growth. An application of 30 pounds of nitrogen
(equivalent to 250 pounds of dried blood or 450 of cot-
ton-seed meal), 40 of phosphoric acid (equivalent to
300 pounds of acid phosphate), and 60 of potash
(equivalent to 120 pounds of muriate of potash),
would provide for a marked increase in yield.
Wheat and Rye Forage
In the growth of cereal grains, the object is to
secure as large a yield of grain as is possible under
WHEAT AND RYE FORAGE 245
the conditions of climate and season, and only such
development of leaf and stem as will contribute to a
maximum yield of grain. Hence a too liberal nitrog-
enous fertilization which encourages this form of
growth may result in too great a proportionate yield of
straw. This objection becomes an advantage when the
cereals are grown for forage.
The cereal crops, wheat and rye, if seeded in the
fall, should, therefore, receive a fertilizer which shall
especially promote leaf and stem growth; and to ac-
complish this purpose in the best manner, a rapid early
fall growth, and a consequent deep rooting system, as
well as an early and rapid spring growth, should be
encouraged. Fertilizers most suitable are rich in
nitrogen and phosphoric acid, and should contain
potash also, if the land has not been previously well
supplied with this element. The larger proportion of
the nitrogen, however, should be applied in available
forms as a top-dressing in the spring, rather than at
time of seeding, thus reducing the possible loss of this
element during the winter and early spring through
_ leaching, besides providing the plant with it when
most needed, and producing a crop richer in nitrog-
enous substance.
The ranker growth and somewhat coarser product
resulting from this method of fertilization, while not
desirable for grain crops, is not a detriment when the
product is eut in its green stage for feeding, and the
larger growth is accompanied by greater succulence.
Where these cereal grains are sown mainly as
eatch crops following a corn crop which has been
946 FERTILIZERS
liberally fertilized with the minerals phosphoric acid
and potash, the application at time of seeding may be
light, and may consist only of nitrogen and phosphoric
acid,—for example, from 200 to 400 pounds per acre of
a dissolved bone; and the top-dressing in the spring
need not exceed 100 pounds of nitrate of soda per acre
for the wheat, and 75 pounds per acre for the rye.
For lighter soils, or for those not previously well fer-
tilized, much heavier applications not only are required,
but all of the constituents should be ineluded, and
the top-dressings should be made in spring, as already
pointed out.
Spring Rye
For spring rye, an application of a fertilizer fur-
nishing 10 pounds of nitrogen, 20 of phosphorie acid
and 10 of potash per acre would be a sufficiently
liberal dressing for the crop on good soils, sinee the
plant possesses good foraging powers, though it is not
so desirable a forage crop for northern climates as the
winter rye. The nitrogen, in any. case, should be in
quickly available forms.
Oats
Oats and millet are also suitable crops for forage
purposes, and are largely grown; the first, because it
is adapted for cool, moist weather, and makes a rapid
early growth, and the second, because adapted for late
spring seeding and for summer conditions.
The oat crop for forage purposes is even more
A PECULIARITY OF THE OAT CROP QA47
generally benefited by manuring than when grown for
the grain, and the constituents particularly useful are
nitrogen and phosphoric acid, though on sandy soils,
and on those of medium fertility and not previously
fertilized with potash, this element should also be
added.
A good dressing, keeping in mind the value of the
possible increased yield, may consist of 12 pounds of
nitrogen, 20 of phosphoric acid and 10 of potash,— the
nitrogen largely in the form of a nitrate and the phos-
phorie acid in soluble and available forms.
The oat crop is peculiar in that shortly after the
germination of the seed, there usually oceurs a period
of a week or ten days during which the growth is ex-
tremely slow, which experienced farmers call the ‘ pout-
ing” period. While the exact cause of this well-known
habit is not understood, it is believed to be due
in part to the absence of available plant-food of the
right sort early in the season, since liberal applications
of nitrates and superphosphates seem to shorten the
period of “pouting,” if not altogether preventing its
occurrence. Its avoidance for grain crops, while im-
portant, is not so important a matter as in the ease
of forage crops, since an extension of the period of
growth simply delays ripening, while in the latter,
delays not only prevent maximum growth within a
certain time, but seriously interfere with rotations.
Winter oats, which are successfully grown in the
southern sections of the country, should be fertilized
at time of seeding practically in the same manner as
wheat; that is, dressings furnishing small amounts of
248 FERTILIZERS
nitrogen and considerable phosphoric acid, to be fol-
lowed in spring with a top-dressing of nitrate of
soda, not to exceed 100 pounds per acre.
Oats and Peas
Where oats are grown with field peas for the pur-
pose of supporting the vines, as well as to obtain a
larger yield than from either alone, the fertilizer
should also contribute toward the inerease in the
pea crop, and hence a greater abundance of the
minerals should be applied, though it is very desir-
able in this case, too, to encourage the rapid growth
of the oats by reasonably liberal supplies of available
nitrogen.
Barley and Peas
The growth of this combination of plants is a
desirable one when late fall forage is needed, and as
a crop is well adapted for fall conditions. The ferti-
lization should be liberal, in order to encourage a
rapid and large appropriation of food, which may be
elaborated after light frosts oceur. An application
of 200 pounds per acre of a mixture of 100 pounds
of nitrate of soda, 175 of acid phosphate and 25 of
muriate of potash, will furnish sufficient and good
proportions of the plant-food constituents.
Millet
The various kinds of millet are eminently sur-
face feeders, and are particularly benefited by lberal
THE FERTILIZATION OF MILLET 949
applications of all the fertility elements. In fact,
maximum forage crops of this plant cannot be ob-
tained except when there is present in the soil such
an abundance of all of the fertility elements as to
enable a continuous and rapid growth. Both the
nitrogen and phosphoric acid should be largely in
immediately available forms; hence nitrates and super-
phosphates are recommended. The potash may be in
the form of muriate. A crop of ten tons per acre of
millet forage, of any of the Japanese varieties, which
are very suitable for this purpose, will remove 50
pounds of nitrogen, 25 of phosphorie acid, and 110
of potash, practically all of which food is absorbed
from the immediate surface soil. Good crops fre-
quently reach this assumed yield; hence, unless the
Jand is in a high state of fertility, or has been pre-
viously fertilized, it is necessary, in order to obtain a
fair crop, to furnish by direct application at least one-
half of the nitrogen and potash, and as much phos-
phoric acid, as are contained in the crop. These
amounts and kinds of plant-food could be practically
supplied by a dressing of 450 pounds of a mixture
made up of 150 pounds of nitrate of soda, 200 of acid
phosphate, and 100 of muriate of potash, and such
dressings have given excellent satisfaction in the
New Jersey experiments with forage crops.
CLOVERS AND OTHER LEGUMES
These are among the most valuable of our summer
forage crops: first, because of the time of their
950 FERTILIZERS
growth, they furnish food before spring-sown erops
are ready; second, because of their power of ac-
quiring food from sources inaccessible to the cereals,
they are less exhaustive; and third, they are espe-
cially rich in the compound protein, the most useful
substance contained in feeds. Since these crops gen-
erally grow well on soils of medium fertility, many are
inclined to regard them as able to subsist and make a
good crop without liberal fertilization. It should be
remembered, however, that the power which these
plants possess of acquiring nitrogen from the air
depends largely upon the supply at their command of
the mineral elements, phosphoric acid, potash and
lime; the presence of these is of primary importance,
and good crops cannot be grown on land deficient in
these elements. In any event, therefore, liberal sup-
plies of the minerals should be provided, in order that
maximum yields may be obtained. On soils of medium
fertility which are fairly well supplied with vegetable
matter, the need for nitrogen is not marked, even in
the early growth of the plant. On lghter soils, how-
ever, a nitrogenous fertilization is often serviceable,
because supplying nitrogen before the plant has ac-
quired the power of obtaining it from the air. This
practice enables the plant to make an early start, and
prevents the delay in growth which sometimes occurs,
particularly on light soils, during the period imme-
diately after germination, when the plant is unable to
obtain its nitrogen from sources other than the soil.
A green forage crop averaging 10 tons per acre re-
quires, on the average, about 30 pounds of phosphoric
FERTILIZERS FOR SUMMER LEGUMES 951
acid and 100 of potash, and the nitrogen which neces-
sarily accompanies these amounts of minerals will
reach, on the average, 100 pounds. If this element is
drawn from the air, because provided with an abun-
dance of minerals, it is manifestly economy to supply
the full amount of these required, rather than omit
them, and thus to limit the plant’s power of acquiring
this expensive element, since the value of the 100
pounds of nitrogen gained is greater than the cost of
both the phosphoric acid and potash required.
Cow Pea and Soy Bean
The clovers, which range in their length of life
from annuals to perennials, are, too, able to obtain
their necessary supplies of minerals more readily from
soil sourees than the distinctly summer crops, as the
cow pea and soy bean, because of the longer period of
preparatory growth in the ease of the former. That
is, clover or vetch, while it does make a very rapid
growth through a short period, does not obtain all
of its food during that period. In its preparatory
stage of growth—fall and early spring—a very con-
siderable amount of food, the larger proportion, in
many instances, is obtained, which in its later stages
of growth, is simply distributed throughout the entire
plant; while the cow pea and soy bean, on the other
hand, must obtain the entire amount of food needed
for their growth and development during a short
period, and these crops reach their best stage of
development for forage in two and one-half to three
252 FERTILIZERS
months from time of planting. Hence, these crops,
which possess apparently greater foraging powers, and
make their development during the season when con-
ditions are most favorable for rapid change of in-
soluble to soluble food in the soil, require, when the
conditions of the land are the same in each ease, a
relatively greater abundance of the mineral elements
than do the clovers, which can acquire food through
a longer period.
An application of 3800 pounds per acre of a mixture
of 200 pounds of acid phosphate and 100 of muriate
of potash, which supplies 25 pounds of phosphoric
acid and 50 of potash, would, on medium soils, be
regarded as a sufficient annual dressing for clover crops;
whereas, in the case of the purely summer crops, the
application could be inereased one-half with profit.
In the case of the summer erop, the phosphoric acid
should. be in a soluble form, because it is not economy
to depend upon the conditions of climate, soil and
season to change insoluble forms rapidly enough to
provide for the continuous feeding of the plant, while
for the clovers, less available forms may be used with
advantage.
Alfalfa, or Lucerne
This valuable crop, which was not formerly regarded
as well adapted for the eastern states, can be success-
fully and profitably grown if the soil is_ sufficiently
deep and open and naturally well drained, and pro-
vided it is supplied with an abundance of mineral
ALFALFA OR LUCERNE 2060
food, consisting of phosphoric acid, potash and lime.
Its habits of growth are such as to enable the harvest-
ing of three or four green forage crops, and at least
two hay crops annually. In order to meet the large
plant-food demands thus made, the fertilization pre-
vious to seeding must be not only liberal, but frequent
top-dressings should be made. The phosphoric acid
for these dressings should preferably be drawn from
superphosphates, in order that ready distribution may
be accomplished, while a large portion of that con-
tained in the preparatory dressing may consist of the
less soluble forms, as ground bone, natural phosphatic
guanos, and fine ground rock phosphates.
Twenty tons of alfalfa green forage, which may be
regarded as a good annual yield for this plant from the
two to four cuttings that may be made, will contain
250 pounds of nitrogen, 50 of phosphoric acid and
275 of potash. Assuming that the demands for soil
nitrogen are confined to a short period immediately
subsequent to the germination of the seed, the total
required plant-food is still considerable, and is es-
- pecially severe upon the potash compounds of the soil.
Hence, the fertilizers supplied should be particularly
rich in this element. For eastern conditions, where
soils possess a medium rather than a high potential
fertility, heavy dressings of the minerals should always
be made. <A good preparatory fertilizer may consist
of 20 pounds of nitrogen, equivalent to 125 pounds
of nitrate of soda; 75 of phosphoric acid, equivalent
to 600 of acid phosphate; and 200 of actual potash,
equivalent to 400 pounds of muriate of potash per
254 FERTILIZERS
acre; and annual top-dressings should provide at
least 30 pounds of phosphoric acid and 100 of actual
potash for the same area.
Inasmuch as careful preparation of soil is necessary
previous to seeding, and since this can preferably be
accomplished by the growth of cultivable crops, the
fertilizers may be also partly applied to these rather
than all at once immediately preceding the seeding,
thus limiting danger of injury to germination by an
application of so large a proportion of salts.
Need of Lime for Legumes
Another point that should be remembered in the
fertilization of the leguminous plants is their need for
lime. This is true of the elovers particularly, not only
for the purpose of providing the plants with a suf-
ficient amount of this element, but in order that any
possible acidity of soil may be corrected, since the bac-
terial life in the soil, which is essential in order that
the plant may acquire its nitrogen from the air, is
discouraged rather than encouraged by ‘the presence of
acid. Hence, all soils that are used for the frequent
growth of leguminous crops should receive a dressing
of lime, preferably in the fall; 25 bushels of stone
lime per acre, once in four or five years, is a suf-
ficient amount for medium soils.
The necessity for fertilization, and the method
employed in “intensive” practice, are illustrated by the
following scheme of growing soiling crops, now prac-
ticed at the Experiment Farm in New Jersey. If an
SOILING-CROP ROTATION aa
abundance of food is not supplied, the continuous
feeding and consequent constant and rapid growth of
the plants, which are primary necessities of the sys-
tem in order to maintain the rotation and to obtain
maximum yields, are prevented. With proper man-
agement in other respects, the scheme of rotation and
fertilization will result in a gradual increase in the
fertility of the soil.
Scheme of Soiling Crops
No. of
2 Acre
Crop
Rotation
Crimson Clover.
Barley and Peas.
Crimson Clover.
i Se <3 ar
w
i)
J
ia°)
|
¢ &
=}
a
ae)
fae)
9
n
Aug. 11,’97
Ane. 24,7971 f
..-Aug. 25,’98
Time of
Seeding
June 20, a8}
50 Ibs
June 10,98
50 Ibs
Aug. ¥, 298
75 Ibs.
00 Ibs.
. Muriate of potash
100 Ibs.
50 lbs.
50 lbs.
25 Ibs.
100 lbs.
50 Ibs.
50 lbs.
May 20,798 100 Ibs.
Amount of
Fertilizer Applied
100 Ibs.
50 lbs.
100 Ibs.
50 Ibs.
50 lbs.
25 Ibs.
.Aug. 25,9810 Ibs.
50 Ibs.
Acid phosphate
Muriate of potash
Acid phosphate
Ground bone
} ae
Muriate of potash
Nitrate of soda
Acid phosphate
\ Oct
Muriate of potash
Acid phosphate
Acid phosphate
Ground bone
Muriate of potash
Nitrate of soda
Acid phosphate
Muriate of potash
Acid phosphate
s. Ground bone
50 lbs.
75 lbs.
150 Ibs.
Muriate of potash
Nitrate of soda
Acid phosphate
Muriate of potash
Nitrate of soda :
Time of
Harvesting
20,798
. 20,’98
. 25,798
10,’98
g. 10,98
. 20,98
20,98
1, ’98
256
No. of
Acre
Time of
Seeding
Crop
Rotation
DSS ee A, « May 10,’98
t
Sept. 28,97
Oats and Peas... April 20, ial
Soy Beans....... Aug. l, 98 {
|
:
|
.
|
100 lbs
Sept. 29,07{
Millet
Cow:Poas .... 2. July 20,798
Oats and Peas... April 10,’98
25 Ibs
Soy Beans....... July 1, 984
Barley and Peas.
Fertilizer Applied
50 lbs.
100 lbs.
50 lbs.
50 Ibs.
25 lbs.
Barley and Peas..Aug. 10/9830 Ibs.
50 lbs.
150 lbs.
50 lbs.
25 lbs.
25 lbs.
100 lbs.
25 Ibs.
50 Ibs.
200 Ibs.
. Muriate of potash
150 lbs.
50 lbs.
25 lbs.
75 Ibs.
Shiptine main May 1, 8 10 Ibs.
75 Ibs.
200 lbs.
100 lbs.
25 lbs.
100 lbs.
. Ground bone
50 lbs.
200 Ibs.
100 lbs.
25 Ibs.
Sept. 1, af 100 Ibs.
50 lbs.
FERTILIZERS
Time of
Harvesting
Amount of
Nitrate of soda
Acid phosphate
Ground bone |
Muriate of potash
July 10,’98
Nitrate of soda
Acid phosphate
a 10,’98
Muriate of potash
Acid phosphate
Ground bone
Muriate of potash
June 5, ’98
Nitrate of soda
Acid phosphate
Ground bone
Muriate of potash J
Acid phosphate
June 20,’98
Oct. 1, ’98
Acid phosphate
Ground bone
bata 1, 798
Muriate of potash
Nitrate of soda
Acid phosphate
\y uly 1, 98
Muriate of potash
Acid phosphate }
Asse ot oeee Sept. 20,°98
Nitrate of soda
Acid phosphate June 10,’98
Muriate of potash
Acid phosphate
t. 1, 9
Muriate of ee Sep eee
Nitrate of soda
Acid phosphate
}avor 1, ’98
Muriate of potash
FERTILIZERS FOR ROOT CROPS
Time of
No. of
Seeding
Acre
Crop
Rotation
Oats and Peas...April 1,’98
8 Gow Peas ...s... June 15,7984
100 lb
25 Ibs.
Barley and Peas..Aug. 20,9810 Ibs.
50 Ibs.
25 lbs.
Rye and Vetch...Sept. 10/97 150 Ibs.
75 Ibs.
Fertilizer Applied
25 lbs.
100 lbs.
25 lbs.
50 lbs.
200 Ibs.
s. Muriate of potash
. Acid phosphate
50 Ibs.
50 Ibs.
25 Ibs.
Barley and Peas..Aug. 15,9810 Ibs.
50 Ibs.
207
Time of
Harvesting
Amount of
Nitrate of soda
Acid phosphate
Ground bone
Muriate of potash
Acid phosphate
June 1, ’98
}aug. 15,’98
Nitrate of soda
Acid phosphate } oe 20, ’98
Muriate of potash
Nitrate of soda
Acid phosphate
Muriate of potash
May 5,
Ground bone
Muriate of potash
Nitrate of soda
Acid phosphate
Muriate of potash
Oct. 15, ’98
This scheme, which provides for two or three
crops each season, has proved entirely practicable
and successful when liberal fertilization is practiced,
as here indicated.
ROOT CROPS
These crops are, as a class, exhaustive of plant-
food elements, much more so, in proportion to the dry
matter contained in them, than the cereals or legumes.
It will require, for example, 20 tons of topped fodder
beets or turnips to furnish as much total food as is
contained in 10 tons of corn forage or silage, as the
Q
958 FERTILIZERS
former seldom contain more than 10 per cent of dry
matter, whereas the latter frequently contain more than
20 per cent; yet on the average, 20 tons of roots will
contain 60 pounds of nitrogen, equivalent to 400
pounds nitrate of soda, 35 of phosphoric acid, equiva-
lent to 800 pounds of acid phosphate, and 150 of
potash, equivalent to 300 of muriate of potash, which
amounts are far in excess of those contained in a corn
crop, particularly of the minerals, phosphoric acid and
potash. The nitrogen demands for the two crops are
practically identical. In the case of both kinds of
crops, these fertility constituents are obtained entirely
through the roots from soil sources.
In respect to fertilization, however, the root crops
may be divided into two groups, very similar in their ~
demands for plant-food, the first to include mangel-
wurzels, fodder beets, sugar beets and carrots, and the
second turnips, swedes (ruta-bagas) and rape.
Fertilizers for Fodder Beets, Sugar Beets and Carrots
The first group requires that the fertilization with
nitrogen and phosphoric acid shall be liberal, and that
these constituents shall be applied in readily soluble
forms, in order to meet the large and early demands of
the plant for them. Potash is also a very essential
constituent, particularly upon soils of alight, sandy
character ; upon clay loams, the plant is better able to
obtain this element.
In order to obtain a large amount of actual food by
the growth of these crops, a large tonnage must be
FODDER BEETS, SUGAR BEETS, CARROTS 259
secured, and a large yield cannot be obtained unless
provision is made for a continuous and rapid growth,
and this again cannot be accomplished without an
abundant supply of nitrogen and phosphoric acid,
which, as already stated, are the elements which, more
than any others, seem to rule the crop.
In the case of sugar beets, the suggestion for fer-
tilization when grown for sugar (Chap. XI), may be
followed in large part. That is, particular attention
should be given to the supply of nitrogen and phos-
phorie acid, though when grown for forage it is im-
portant not only to secure sugar, which constitutes a
large proportion of the dry matter, but that the gross
yield shall be much greater than in the former case.
Hence, a liberal use of yard manure need not be
avoided, and heavier dressings of nitrogen, which
stimulates early leaf growth, may be made.
For both fodder beets and sugar beets, an applica-
tion per acre of 40 pounds of nitrogen, 50 of phos-
phorie acid and 100 of potash, or 1,000 pounds of a
fertilizer, containing—
|S CES SR eg a nh i a nee 4%
Available phosphoric acid. ........ 5 %
me NA PR eer ets, Oe ee or oe KR 10 %
should insure a very considerable increase in yield on
soils of medium fertility, provided the elements are
drawn from the best materials. On light soil the fer-
tilization should be still heavier, and the proportion
of nitrogen increased. In fact, on soils poor in fer-
tility and possessing good physical qualities, the con-
260 FERTILIZERS
tributions of plant-food by them may be largely ig-
nored, and the dressings made large enough to supply
the entire amount of food required by the crop. On
such soils the nitrogen should preferably be applied in
fractional dressings and in quickly available forms,
because it is essential that this element should be
quickly absorbed by the growing plant. The minerals
may be all applied in one dressing, though preferably
in two, in order that the constituents may be well
distributed throughout the surface soil. To better
accomplish this, cultivation should follow each
application.
Turnips, Swedes and Rape
In the case of the second elass of crops, it has
been shown that they are able to extract their phos-
phoriec acid from combinations not readily accessible
to other plants. In fact, they respond so promptly to
applications of this element, that frequently too little
attention is given to the supplies of the other elements;
yet in order to obtain satisfactory yields, these must
also be added. An analysis of the turnip, for example,
shows it to be rich in potash; hence it must naturally
be a voracious feeder upon compounds containing this
element, and while it seems to obtain it more readily
from soil sources than many other plants, these sup-
plies should not be depended upon, even on good soils,
to meet its entire: needs in this respect. A _ liberal
supply of nitrogen is also demanded, particularly dur-
ing the early growth. An application of a fertilizer
TURNIPS, SWEDES AND RAPE 261
containing 20 pounds of nitrogen, derived in part
from nitrate, 40 of phosphoric acid, derived in large
part from phosphates, and 40 of potash, derived from
muriates, would be a fair dressing on soils of good
character. On the poorer soils, the application of the
constituents of the same kind and forms should be
very largely increased.
In these crops, as in those already mentioned, it is
essential—and success depends upon this as much as
upon any other factor—that the growth should be con-
tinuous; and in order that there shall be no delay in
this respect, there must be an abundance of available
food always at their command.
TUBER CROPS
In many sections the potato and sweet potato are
grown for roughage. For these crops no different
fertilization is recommended than that already outlined
(Chapter XI) for the crops when grown for market,
though in the case of sweet potatoes, soils not adapted
for the growth of marketable tubers may be used.
CHAPTER XIII
MARKET-GARDEN CROPS
A KNOWLEDGE of the principles of plant nutrition
is perhaps more serviceable in market-gardening than
in any other line of farming. This branch of farming
eannot be profitably conducted either without suitable
soils or without an abundant supply of plant-food.
Both of these conditions are essential for the growth
of high-class products.
THE YIELD AND QUALITY DEPENDENT UPON
CONTINUOUS AND RAPID GROWTH
In these days, it is not only the yield of a definite
area that must be considered, but the edible quality of
the products that are put upon the market. Quality
depends upon, or is measured by, both appearance and
palatability ; and palatability is determined by the
suecculence and sweetness of the vegetable, or its free-
dom from bitterness, stringiness, and other undesirable
characteristics which frequently exist, and which can
be largely eliminated, provided the grower is thoroughly
familiar with his business, assuming, of course, that
varieties are the same in each case. It has been dem-
onstrated that market-garden crops of the best quality
are those which are grown under conditions which
(262)
FERTILIZATION IMPROVES QUALITY 2655
permit of a continuous and rapid development. Any
delay in the growth of a radish or of lettuce is largely
responsible for the sharp taste and pungent flavor of
the former, and the bitterness and toughened fiber of
the latter. The same principles hold true of early
table beets and turnips. The beets become stringy and
wiry in character, and are less palatable if during the
period of normal growth there has been any delay. In
a time during which there has been no progress the
fibrous portion of the vegetable is toughened, and
exists in too great proportion. In the case of the
early turnip, if any delay in growth occurs, the quality
is injured, and the peculiar, pleasant flavor, a charac-
teristic of the perfect vegetable, is changed ; it becomes
unpleasant. The unfavorable conditions of growth
‘seem to cause more or less reversion to the character
of the original plant from which the improved type
has been derived, mainly through selection and im-
proved methods of cultivation.
All these conditions of growth are not absolutely
under the control of the grower; as, for example, a
lack of sufficient moisture and sunshine, the latter of
which is certainly beyond his power to control. But
given good natural conditions in respect to soil, and a
favorable season, the one thing that more than any
other controls the yield and quality of market-garden
products is plant-food of the right amount and kind.
In other words, in crops of this sort, any limitation in
this respect usually results in a disproportionate re-
duction in profits. Only under exceptional cireum-
stances is it economical to depend upon natural soil
264 FERTILIZERS
conditions for profitable crops, however favorable such
conditions may be, because in successful practice the
cropping is in the highest degree “intensive,” and even
the best soils are liable to be deficient in some essen-
tial feature.
It might seem from the discussion thus far, that for
these crops the recommendations as to methods of
fertilization might be briefly though fully expressed
as follows:
Apply a reasonable excess of all of the essential
fertilizer constituents to all of the crops. Neverthe-
less, because of the peculiarities of growth of the
different plants, as well as the different objects of their
growth, distinctions should be made in reference to the
kinds and amounts of plant-food applied, and these
distinctions should be borne in mind, in order that the
most profitable returns may be secured. Market-gar-
den crops may, however, be grouped according to
similarity, both in character and object of growth,
and each group fertilized in a similar manner, which
obviates the necessity of extra labor in the preparation
of fertilizers. :
ASPARAGUS
Asparagus is one of the very important vegetable
crops, and perhaps no other renders so profitable a
return for proper manuring and fertilizing. It differs
from the majority of the others in two essential par-
ticulars. First, it is a perennial, the length of life
of a bed depending largely upon the treatment; and
FERTILIZERS FOR ASPARAGUS 265
second, only one crop can be obtained in a season—it
occupies the land to the exclusion of other crops.
Hence, special efforts should be made to obtain as
large a crop as the conditions of season and climate
will permit. With this plant the yield and market
quality of the crops depend upon the number and size
of the shoots. In respect to quality, the demands of
the different markets vary. Some of them require that
the shoots shall be bleached and so eut as to present
only a green tip, the remainder being perfectly white,
while others demand that the shoot shall be green.
But in both eases, the size of the shoot determines
salability, and the size is largely measured by the
methods observed in feeding the plant when other
conditions are favorable; that is, if not injured by
disease or insects. Small, spindling shoots usually
indicate that the crop has not been well cared for, or
that the plant has been imperfectly nourished.
The root is enlarged and invigorated by the char-
acter of the growth of the tops, or summer growth of
the plant after cutting is finished, and it is obvious
that the manuring should be such as to encourage not
only a rapid growth of shoots early, but a large and
vigorous growth of tops later, which assists the growth
of the roots in which energy is stored up for the pro-
duction of the crop in the following year. Hence,
not only the character but the method of fertilization
is important, and it differs from that recommended
for those plants which grow from the seed in one
season and which must depend upon what they are
able to acquire during their short period of growth.
266 FERYILIZERS
The Use of Salt
It was formerly believed that one of the most
important ingredients of manures for the asparagus
plant was common salt, and that in any fertilization
this substance should occupy a_ prominent part.
Experience has shown, however, that while salt may
not be harmful, there is no real fertility value in it.
The crop may be profitably grown without its appli-
eation, though it does no harm, and there is no objec-
tion to its use except on the ground that it adds no
essential fertility element, and its indirect benefit may
be obtained more cheaply by the use of other ma-
terials, which contain salt as a normal ingredient,—
for example, kainit, the crude potash salt, which is
one-third salt, though its market price is based solely
upon its potash content.
Fertilizers that Have Proved Useful
Fertilizers which have been found very useful for
asparagus are those which contain food both in im-
mediately available and in gradually available forms.
During the early growing season, the available food
may be appropriated rapidly enough to cause an in-
erease in the yield of shoots of that year; and inas-
much as the plant continues to grow until winter, the
food that becomes gradually available is appropriated
later, and contributes to the strength and vigor of
the roots upon which the next year’s crops depend.
Furthermore, because the crop is gathered from the
USE OF A BASIC FORMULA 267
early shoots, which are continuously removed for
from one to two months, the root is continuously
drained of its stored-up material, and at the end of
the cutting season it has been very much reduced in
vitality ; wherefore it is particularly desirable that
available food be applied at this time also, in order
to encourage a rapid and vigorous growth of the
top, which aids in the storing up of food in the
root. A fertilizer containing —
CETTE gS ae ere ae a te ace 4%
Phosphorie jeid. . . . . Pie Ae ae me ASC 8 %
RMMNMT GEER eo cs x aS et a oe RS 10 %
the nitrogen to be drawn from both soluble and
organic sources, and the phosphoric acid from both
superphosphate and ground bone, or tankage, and the
potash from muriate, may be applied previous to set-
ting the crowns, at the rate of 1,000 to 1,500 pounds
per acre, and thoroughly worked into the soil.
A Basic Fertilizer for Market-garden Crops
For market-garden crops, a fertilizer of the above
composition may be regarded as a basic mixture, which
may be applied to all of the crops, leaving the specific
needs of the different plants to be met by top-dress- |
ings, or applications of the other constituents. The ferti-
lizer ingredients, nitrogen and phosphoric acid, should
preferably consist of the different forms, rather than
to be all of one form, though the cost of the element
will naturally regulate this point to some extent.
968 FERTILIZERS
That is, a part of the nitrogen should be nitrate or
ammonia, and a part organic; a part of the phos-
phorie acid should be soluble (from superphosphates) ,
and a part insoluble (from ground bone, tankage or
natural phosphates). The soluble portions of both
nitrogen and phosphoric acid contribute to the im-
mediate needs of the plant, and the less soluble to
its continuous and steady growth, and to the poten-
tial fertility of the soil.
For asparagus, this basic fertilizer may be applied
at this same rate,—1,000 to 1,500 pounds per aecre,—
at the time of setting the crowns, or even in greater
amounts from year to year, preferably early in the
spring, in order that the plant may have the whole
season for the appropriation of the food.
- The specific fertilizer, in addition, should contain
immediately available forms of food, and should be
applied preferably immediately after or during the
latter period of the cutting, in order to feed at once,
and thus stimulate and strengthen the plant in its
condition of lowered vitality, due to the continuous
and large removal of the shoots. This application
should also be liberal, since, as already indicated,
limitations at this time may result in a greatly de-
creased yield and a poorer quality of product the
next year, and hence a reduction in profit. The best
growers apply, in addition to the fertilizer recom-
mended, and after cutting, not less than 250 pounds
of nitrate of soda, 300 of superphosphate, and muri-
ate of potash, or kainit, equivalent to 100 pounds of
actual potash,
FERTILIZERS FOR PEAS AND BEANS 969
These recommendations as to the amounts of fer-
tilizers may seem rather large to those who have
been accustomed to light applications, but they are
the minimum rather than the maximum amounts, as
many growers have learned that the extra amounts
applied are preferable to the smaller amounts, con-
tributing not only to the length of life of the plant,
but also to the total yield and size of the shoots, as
well as to their edible quality, which is measured by
their suceculence and flavor.
These suggestions as to fertilizers are for condi-
tions where large amounts of organic or natural ma-
nures are not readily obtainable. When these are
used, they may serve instead of the basic fertilizer,
but cannot well substitute the special applications
‘of artificial fertilizers made after cutting is finished.
PEAS AND BEANS
Peas and beans of the various kinds and varieties
belong to the legume family, and possess the power
of acquiring nitrogen from the air; they are, therefore,
ordinarily placed in a separate class in respect to their
fertilization with nitrogen. When they are grown as
market-garden crops, however, it is frequently the
wiser economy to apply nitrogen, particularly if they
are raised upon land which has not been previously
planted with these crops, and thus may not possess
the specific nitrogen-gathering bacteria: because it is
imperative that the plants should not only have an
abundance of all of the food constituents, but that
970 FERTILIZERS
their food should be such as to cause as long a crop-
ping period as possible, and nitrogen will contribute
to this end. Hence, in the fertilization of these crops,
while the minerals are the primary constituents needed,
nitrogen should also be applied, and it should prefer-
ably be in the organic forms, which encourage a longer
period of growth, rather than in the single, active-
form nitrate, more generally recommended for the
quick-growing market-garden crops, because its com-
plete solubility and immediate availability encourage
a rapid growth and short period of development. The
basic fertilizer recommended, if applied at the rate
of 500 to 600 pounds per acre, will usually furnish
sufficient nitrogen, and may, if necessary, be supple-
mented by the application of amounts of superphos-
phate and potash salts which will add from 20 to 30
pounds of phosphorie acid, and 60 to 75 of potash.
BEETS AND TURNIPS
The early table beet and the early turnip are very
important market-garden crops. Wherever grown,
whether in the South for the northern market, or in the
middle states for the near-by market, earliness is a
primary consideration ; and the earliness of the crop is
determined largely by the amount and availability of
the nitrogen and phosphoric acid applied. These are
the two elements which, more than any others, modify
and dominate the growth of these plants, and con-
tribute to their profitable production as early market-
garden crops. In the case of early turnips particu-
Lar A
EARLY BEETS AND TURNIPS ait
larly, a difference of two or three days in the begin-
ning of the harvest will often determine the profit or
loss upon the crop. The experience of many growers
confirms the view that for no other crop is the necessity
for right fertilization more important. Since the early
growth of these crops takes place before active nitrifi-
eation begins in the soil, dependence for this element
must be placed upon the nitrogen applied, and it is
desirable not only that the soils should be well supplied
at the time of planting with all of the constituents,
but that frequent top-dressings of the soluble nitrate
shall be made. Top-dressings are recommended be-
cause the application of a sufficient amount of the
nitrogen in this form at the time of seeding might
result in its considerable loss, since at this season rains
often occur which are frequently so heavy as to cause
a leaching of the nitrates into the drains or into the
lower layers, and thus prevent the continuous feeding
of the plant, and a consequent delay in growth.
An application, therefore, of from 1,000 to 1,500
pounds of a high-grade fertilizer, one of the compo-
sition of the basic fertilizer already suggested (p. 267),
is frequently employed at the time of seeding; followed
by a top-dressing of from 50 to 100 pounds of nitrate
of soda per acre once every week or ten days, for at
least three or four weeks after the plants have well
started. It will meet the requirements for added fer-
tility. Such a practice, under average seasonal condi-
tions, insures a continuous and rapid growth, and ob-
viates to some extent the dangers liable to follow from
too much rain or from drought. The frequent applica-
PA he FERTILIZERS
tions prevent losses from leaching if heavy rains follow,
and, except in case of excessive and prolonged drought,
the nitrate remains in solution, and is ready to be
immediately absorbed by the plant. The advantage of
earliness which is gained by the use of apparently
excessive amounts of nitrogen is two-fold: a higher
price is received for the product, and the cost of labor
per unit of income is less. Quite as large yields may
be obtained by smaller dressings, but the net {in-
come is reduced as the time necessary for the growth
of a marketable beet or turnip is increased. See also
Chapter XII, in reference to this subject.
CABBAGE, CAULIFLOWER AND BRUSSELS SPROUTS
These large-leaved plants are all voracious feeders,
and are specifically benefited by large applications of
nitrogen and of phosphorie acid. Heavy applications
of the basie fertilizer (p. 267), which is excellent,
should be supplemented upon good soils with additions
of nitrogen and phosphoric acid, and upon light soils,
potash may also be added. Notwithstanding the fact
that these crops are particularly benefited by nitrogen,
the character of the edible portion or head of the dif-
ferent plants is very largely influenced by the nature of
the growth. Too rapid an early growth, due to an ex-
cess of nitrogen, frequently results in an abnormal de-
velopment of leaf, which is not accompanied by a
proper formation of the head; hence a part of the
nitrogen essential for the growth of the plant after the
head has begun to form should be applied at this time
FERTILIZERS FOR MELONS 273
in an immediately available form, and a part in forms
which will gradually feed the plant. A good method of
fertilization, in addition to the application of from
1,000 to 1,500 pounds per acre of the basic fertilizer,
therefore, may consist of a top-dressing of 100 pounds
of nitrate of soda and 200 of superphosphate per
acre, after the plants have begun to make growth after
transplanting. After the heads begin to form, another
top-dressing of 200 pounds of nitrate of soda may be
applied, which will contribute toward a rapid and
continuous growth of head, provided an abundance of
the minerals is present, as already indicated.
A number of crops belonging to this group of
plants require, in addition to a sufficient supply of
plant-food, peculiar climatic conditions for their best
crop development. Cauliflower, particularly, not only
seems to be so influenced, but great skill and expe-
rience are required on the part of the grower. It
must be remembered, that while proper fertilization is
essential, it is only one of the primary conditions of
successful culture.
CUCUMBERS, WATERMELONS, MUSKMELONS, PUMPKINS
AND SQUASHES
All these belong to one botanical group of plants,
and are usually adapted for similar climatic and soil |
conditions, though watermelons and muskmelons of
good quality are successfully grown only upon light,
warm, sandy soils. The pumpkins, cucumbers and
squashes may be readily grown to perfection upon the
R
274 FERTILIZERS
colder and more compact clayey soils. All of these
crops seem to require an abundance of vegetable matter
in the soil, in order to make their best growth. Hence,
upon soils deficient in this respect, manures should be
applied which are rich in vegetable matter. Composts
in the hill have proved of especial advantage, as they
seem to encourage an immediate feeding, and prevent
delay in early growth. In the best growth of these
plants it is also necessary that the mineral elements
shall be available, and that the nitrogen shall be of
such a character as to encourage a continuous rather
than a quick growth of vine. That is, unless the
quick-acting nitrates are applied very frequently, they
are less desirable than organic forms of nitrogen. —
Hence, with the usual broadeast application of the
basic mixture at the time of planting, together with a
compost in the hill, further applications of organic
nitrogen should be made, its character to be such as to
promise a relatively rapid change into nitrate. The
basic mixture may be re-enforced by any one of the
following materials: 200 to 300 pounds per acre of
cotton-seed meal, 100 to 200 of dried blood, or 300 to
400 pounds of fine-ground tankage. Any organic sub-
stance whose greater part will decay in one season will
generally give better results than the nitrate, unless
the latter is applied in frequent small top-dressings,
because organic forms of nitrogen provide for a con-
tinuous growth of vine and fruit, while too great an
abundance of immediately available nitrogen as nitrate
is liable to cause too rapid and large growth of fruit
of poor quality. This does not apply in the case of
FERTILIZER FOR CELERY 25
cucumbers for pickling, where a large setting of im-
mature fruits is desired. In this case, nitrogen in the
form of a nitrate, if properly applied, will contribute
to a large setting and a rapid growth of the fruits.
CELERY
Celery is another plant that luxuriates in a soil
rich in vegetable matter, though the peculiar advan-
tage of this natural condition of soil may be largely
met where it is possible to secure an abundance of
water and plant-food in soluble forms. In the ab-
sence of an abundance of water, even the best judg-
ment in application of fertilizers will not result in
satisfactory growth. <A heavy application of the basic
- mixture (p. 267)—a ton per acre, used at time of set-
ting the plants—may be followed with advantage by
frequent and reasonably heavy top-dressings of nitrate
of soda, 100 pounds per acre or more, and well worked
into the soil. This abundance of soluble nitrogen will
contribute toward that rapidity of growth which is
accompanied by the peculiar crispness and sweetness
that gives edible quality to this vegetable. In the
absence of sufficient water and food, not only is the
growth of the plant retarded, but the quality of that
obtained is materially influenced, since the develop-
ment of the bitter flavor and fibrous character that
frequently cause a reduced consumption of this valu-
able plant is apparently encouraged.
What has already been said concerning this vege-
table is true of a number of others: the main thing
2976 FERTILIZERS
is to see to it that such an abundance of available
food of the right kind is provided as to make
possible a rapid growth when other conditions are
favorable. This is one of the primary necessities, if
a high yield of good quality product is obtained.
SWEET CORN
In the case of sweet corn, the early crop is usu-
ally the most profitable. The recommendations that
are made for the fertilization of the field crop do not
apply to this, because the object is not the matured
crop, which makes its greatest development in July
and August, the most favorable season of growth,
but the early green product, which is often harvested
before the field crop has fairly begun to grow. This
early and rapid growth, therefore, cannot be attained
by methods of fertilization suitable for the field crop
(Chapters X and XII). It can be accomplished only
when an abundance of the mineral foods is present,
and when the nitrogen is in part, at least, in forms
which may be directly absorbed, as much growth must
be made previous to the time that nitrification takes
place in the soil.
The large quantity of well-rotted manure which,
‘until recently, was practically the only manure used
for this erop, while extremely valuable, ean be in part
substituted by a liberal dressing of the minerals,
phosphoric acid and potash, and further supplemented
by nitrogen in readily available forms. The use of
the basic formula (p. 267), reénforced by an applica-
NITRATES FOR SPINACH AND LETTUCE QT
tion of nitrogenous materials, partly in the form of
nitrate, and partly in quickly available organic forms,
as blood, cotton-seed meal, or tankage, may be prac-
ticed with advantage.
EGG-PLANT, SPINACH, LETTUCE AND RHUBARB
The egg-plant belongs to the same botanical family
as the potato, and while specifically benefited by the
fertilizers recommended for that crop, is improved
by the further addition of nitrogen, which stimulates
an early leaf growth. Good organic forms are quite
as useful as the nitrates or ammonia, unless the latter
are used frequently as top-dressings.
Spinach -and lettuce, grown for their tops or the
edible portion of the leaf, are encouraged in their
development by an abundance of available nitrogen,
as this element is the one which contributes more
than any other to formation of leaf. Abundant growth
of the right sort is only accomplished when it is pres-
ent in such quantities and in such forms as to con-
tinuously supply the plant with its needs. Reasonably
heavy dressings of the basic formula (p. 267), 1,000
pounds per acre, or over, at time of planting, should
be followed by a top-dressing of 100 pounds per
acre of nitrate after the plants are well started. The
late fall and winter growth of the spinach is espe-
‘cially benefited by the application of nitrates.
Rhubarb is a crop somewhat similar to asparagus,
in that it is a perennial, and that the best fertilization
is one which not only provides food for the growth of
978 FERTILIZERS
the immediate crop, but which encourages the growth
of top after the regular crop is harvested, and thus
restores the vitality of the plant,— which has been
weakened by the continuous removal of the stalk and
leaf,—and enables it to store up energy for the sub-
sequent crop. An annual application of 1,500 pounds
of the basic formula (p. 267) early in the spring,
preferably plowed in, may be followed with advantage
by a top-dressing of 150 pounds per acre of nitrate
of soda in about two weeks after harvesting has be-
eun, and a similar dressing after harvesting has
ceased. These dressings should be cultivated into the
soil, unless immediately followed by rain, which will
distribute the salt into the lower layers of soil. Plants
of this sort, from which only one crop ean be secured,
should be stimulated to the largest possible production.
ONIONS, ONION SETS AND SCALLIONS
The growing of onions, either from seed ‘or from
sets, and the growing of sets according to “intensive”
systems of practice, requires a soil of a suitable physical
character, and also that it shall be well supplied with
all of the essential constituents of fertility. The
minerals should be supplied in abundance by super-
phosphates and potash salts, while the nitrogen should
be supplied in the most active forms, and in even —
larger amounts than for many other crops. The
present systems of growing these crops require that
the sets shall be planted and the seed sown more
thickly than was formerly believed to be desirable,
FERTILIZERS PREFERABLE TO MANURE 279
which permits of a larger yield per unit of area,
though it requires better culture and a very much
larger quantity of available plant-food than was the
ease under the former rather “extensive” systems of
culture. Except in the case of very early onion crops,
immediate rapid growth after setting is not so essential
as in the case of many other market-garden crops, and
in the growing of onion sets, when the soil is richly
provided with food, great care in management is
necessary in order to secure a development of bulb
that shall not be too large, in which case the salable
quality of sets will be reduced. Hence, to avoid this,
the seed should be spread thickly, in rows about
3 inches wide, and the cultivable portion between the
rows about 8 inches wide. With so large a portion of
- the surface area occupied with the crop, the danger of
too large development from heavy fertilization is greatly
reduced.
In growing seallions, the soil should not only be
richly provided with minerals and organic forms of
nitrogen, as in the case of the other, but should be
supplied early with soluble nitrate, in order to meet
the demands for this element before it is available from
soil sources. In the growing of crops which require so
much hand labor as onions, fertilizers are also pref-
erable to yard manures, because they are free from
weed seed. Further, fertilizers do not contribute
toward the development of insects or diseases, as is
sometimes the case with manures, particularly with the
product derived from city stables.
A good general fertilizer for onion sets for soils of
*,
-
I80 FERTILIZERS
fair fertility may consist of about 50 pounds per acre
of nitrogen in organic forms, as dried blood, cotton-
seed meal or tankage, 60 of phosphoric acid, which may
be partly in organic forms, as bone or tankage, and
100 of actual potash, derived from a muriate. The
application of a formula containing—
NaeR en. 220 oh eee ts aya 5 %
PHOSMNOFIG DOU. 5 OF a cu! eee nee 6 %
PO pHele orld A Fleets ote Lc Vien he ee 10 %
at the rate of 1,000 pounds per acre, and well worked
into the soil previous to planting, would furnish these
amounts, and this application, together with a top-
dressing of from 75 to 100 pounds per acre of nitrate
of soda, or 60 to 75 pounds of sulfate of ammonia,
two or three times at intervals of about three weeks,
the first after the crops have well started, would pro-
vide not only an abundance of food of the right sort,
but the nitrogen when needed, without danger of loss.
If the soil has been well dressed with a general
fertilizer, as above described, the scallions should
receive a dressing of nitrate just as soon as growth
begins in the spring, as rapid and early growth at this
season will, other conditions being equal, depend upon
the supply of available nitrogen, and nitrogen in
available forms is not usually present in the soil in
sufficient quantities so early in the season.
In all of the suggestions made as to the fertilization
of market-garden crops, not only has the question of
yield been kept in mind, but also the quality of the
FERTILIZERS VS. MANURES 981
product, which is a measure of salability. The ques-
tion is often raised as to whether the forcing of these
crops by means of active fertilizers may not result in
too coarse and one-sided a growth. Such growth does
frequently follow a heavy fertilization with nitrogen,
if accompanied by too light a fertilization with min-
erals. The tendency of the plant is to make a normal
development when a sufficiency of all of the fertility
elements are present, but in these crops the object is
really a one-sided growth in many eases, since that
growth is usually better adapted for the purpose than
that obtained under what may be regarded as normal
conditions. It must be remembered, too, in the grow-
ing of certain vegetables, such as radishes, celery, etc.,
or those in which the roots are the edible portion, that
- commercial fertilizers do not contribute any undesirable
flavors. In fact, they are often largely responsible
for those peculiar characteristics which give quality;
whereas, when these vegetables are grown by the ex-
clusive and necessarily excessive applications,—if large
yields are to be secured,—of natural manures, unde-
sirable qualities are frequently contributed by them.
CHAPTER XIV
ORCHARD FRUITS AND BERRIES
Ir 1s not until within recent years that the question
of manuring or fertilizing fruit trees and berries has
come to be of particular interest. This is due primarily
to the fact that demands for fruit and berries have
been relatively limited as compared with the staple
crops. Hence, fruit-growing as a business, or on a
commercial scale, is comparatively new, though the
opinion is quite prevalent among fruit-growers that
trees, particularly, are indigenous to most soils, and
erow freely like weeds, and that, therefore, orchard
erops are not as exhaustive of the fertility elements
as Others. They cite, as an argument on this point,
the fact that lands from which timber has been
recently removed are much more _ productive than
those upon. which many regular farm crops have
been grown. Scientific investigation and _ practical
experience, however, teach that forest growth and
fruit growth are quite different in respect to the
needs of fertilizing elements, and that progressive
fruit-culture demands that quite as much attention
shall be given to the matter of providing proper
plant-food as is now known to be desirable for
the other and more common crops of the farm
grown for profit.
(282)
THE GROWTH OF FRUIT CROPS 283 |
FRUIT CROPS DIFFER FROM GENERAL FARM CROPS.
It is obvious that suggestions as to the character
of the fertilization of the cereal crops, grasses and
vegetables, must be somewhat different from these
fruits, because the former differ from the latter not
only in their habits of growth, but in the character
and composition of the crop produced, and in their
relation to soil exhaustion. General farm crops, with
few exceptions, require but one year for the entire
processes of vegetation and maturation. Fruit crops,
as a rule, require a preparatory period of growth of
tree or bush before any crop is produced, which is
longer or shorter according to the kind of fruit.
Furthermore, after the fruit-bearing period begins,
the vegetative processes do not cease, but are coinci-
dent with the growth and ripening of the fruit. The
erop product, or the fruit, also differs materially in
its character from the general farm crop, or from
vegetables, which reach their harvesting stage and
die in one season, because for many kinds a whole
season is required for growth and development.
That is, in fruit-growing it is necessary that there
shall be a constant transfer of the nutritive juices
from the tree to the fruit throughout the entire grow-
ing season, while the growth for each succeeding year
of both tree and fruit is dependent upon the nutrition
stored up in buds and branches, as well as upon that
which may be derived directly from the soil.
“In the next place, the relation of fruit-growing
to soil exhaustion is very different from that in gen-
I84 FERTILIZERS
eral-crop farming, because in orchards there is an
annual demand for specific kinds and definite pro-
portions of soil constituents. It is really a continu-
ous cropping of the same kind, and there is no oppor-
tunity, as in the case of ordinary farm crops, to cor-
rect the tendency to exhaustion by a frequent change
of crops, or the frequent growth of those which re-
quire different kinds and amounts of plant-food con-
stituents.” *
THE SPECIFIC FUNCTIONS OF THE ESSENTIAL
FERTILIZING CONSTITUENTS
It must be admitted, however, that the general
principles of manuring, as applied to farm crops, also
apply to fruit and berry crops; that is, the essential
manurial constituents must be the same.
“A fruit tree will not make normal growth in a soil
destitute of nitrogen. That nitrogen encourages leaf
growth is a recognized fact, and since trees grow by
means of both leaf and root, its presence is required in
the soil in order to promote the growth and extend the
life of the tree. It is very evident, too, that potash is
an essential constituent in the growth of fruits, not
only because it constitutes a large proportion of the
ash of the wood of the apple, pear, cherry and plum,
and more than 50 per cent of the ash of fruit, but
because it forms the base of the well-known fruit acids.
Phosphoric acid is also very essential in order to
* Voorhees, “ Manuring Orchards.” Lecture before Massachusettes Horti-
eultural Society, 1896.
SOILS ADAPTED FOR FRUIT CROPS I85
nourish a tree properly, as well as to insure proper
ripening, though it is apparent from such investigations
as have been made that this constituent is relatively of
less importance than for the cereals.
“Tt is also a matter of common observation, that in
the prodnetion of stone-fruits, particularly, lime is an
important constituent. Its functions seem to be to
strengthen the stems and woody portion of the tree, to
shorten the period of growth, and to hasten the time
of ripening. Fruit trees growing on soils rich in lime
show a stocky, steady, vigorous growth, and the fruit
ripens well, while those on soils which contain but
little lime, particularly the clays, appear to have an
extended period of growth, the result of which is that
the wood does not mature and the fruit does not ripen
properly.” *
THE CHARACTER OF SOIL AN IMPORTANT CONSIDERATION
Soils which possess good mechanical condition,
are rich in the essential constituents—nitrogen, phos-
phoric acid and potash—contain a good _ propor-
tion of lime, and are well drained and cultivated, are
naturally well adapted for fruit trees, as well as for
other crops, and the exhaustion of such soils will not
become apparent for a long time. But soils of this
character are the exception rather than the rule, and
the growth of fruit on those which possess the opposite
characteristics cannot be continued for any considerable
period without an artificial supply of the fertility
** Manuring Orchards.” Massachusetts Horticultural Society, 1896.
I86 FERTILIZERS
elements. In fact, it is doubtful whether it ever pays
to attempt to grow fruits on soils of the latter char-
acter without supplying them with an abundance of
the essential fertilizer elements.
In the matter of berries, which are crops especially
well adapted to soils which possess a light, open
character, but which are not naturally supplied with
the essential plant-food constituents, proper manuring
becomes of even more importance than for the tree
fruits; though, because of their shorter period of life,
one or two good crops may be secured without heavy
fertilization.
On the whole, however, for all of these crops the
great need at the present time is for a larger use of
fertilizing materials, not only because a larger yield
may be obtained thereby, but because the quality of
the product is far superior to that grown under con-
ditions which are not perfect in this respect. Quality,
which is determined by size and appearance, is, other
things being equal, largely dependent upon an abun-
dant supply of plant-food. It is manifestly impos-
sible to include all fruit and berry crops in one general
group, though possessing points of resemblance, be-
cause the different ones vary more or less in their
character. The trees of certain of them are long-lived
—40 years or more,—while others are comparatively
short-lived—10 years or less. In certain of them the
cropping period is short; the fruit ripens at once, while
in others the ripening period extends over a consid-
erable time. They also differ in reference to their
demands for plant-food, certain of them requiring an
NECESSITY FOR CONTINUOUS FEEDING 287
abundance of available food, while others can readily
absorb the food necessary for their growth from rela-
tively insoluble compounds. In the discussion, similar
recommendations may be made in many eases, though it
is desirable that each class of fruits shall be considered
separately, and also that distinctions should be made
between what are regarded as good soils, as medium
soils and as poor soils, in respect to their content of
plant-food.
THE GENERAL CHARACTER OF THE FERTILIZATION
It must be borne in mind, also, that inasmuch as
the fruit crop is not derived from annual plants, but
from perennials, the character of the feeding may be
very different from that in which the entire plant
serves aS a crop, as is the case with the cereals and
most vegetables. Hence, the fertilizers applied need
not all be of such a character as to be immediately
available. That is, the fertilizing materials may be
such as to provide for a gradual and continuous feed-
ing. Those forms which decay relatively slowly are,
perhaps, quite as good, if not better, for many kinds
of fruits than those which by virtue of their solubility
and immediate availability are more stimulative in
their character. Those fertilizers which do not con-
tribute to the immediate feeding of the tree or plant,
but rather add to the reserves of potential plant-food
in the soil, should, however, in many eases be sup-
plemented by those which act more quickly, in order
to supply an abundance of available food at special
988 FERTILIZERS
times and seasons. In general, therefore, a basic
formula, the chief claim of which is that it furnishes
large percentages rather than specific proportions or
forms of plant-food, may be more reasonably adopted
for fruits and berries than for other crops, because
it may be applied with advantage to all of the fruits,
the amounts to be applied to be adjusted to meet the
requirements of the different kinds of crop and the
different kinds of soil. Fertilizers which have been
found to be very serviceable for fruit crops have
been made according to the following formulas, the
materials of which are familiar to all, and may be
readily obtained from dealers: (1) One part, or 100
pounds each, of ground bone, acid phosphate and mu-
riate of potash; or (2), a mixture of one and one-half
parts, or 150 pounds, of ground bone, and one part,
or 100 pounds, of muriate of potash; the mixture of
either to be applied in all cases. For fruit trees on
soils of good natural character, further additions of
more active forms of the various constituents may
not be needed, while on light soils, or those of a me-
dium character, or for berries, they should be added.
The chief point to observe is that an excess of
nitrogen must be avoided, and that if this element is
applied in active forms it should be used at such
times as to enable the plant to appropriate it early
in the season, and thus become assimilated before
the beginning of winter, the danger from too great
an excess of nitrogenous fertilizers being that it
causes a too rapid growth of both wood and fruit,
which do not ripen well.
METHOD OF APPLICATION IMPORTANT 289
THE APPLICATION OF FERTILIZERS FOR FRUITS
A point which should be earefully observed in
the fertilizing of orchards is the method of applica-
tion. The fertilizers should, as far as possible, be dis-
tributed throughout the lower layers of soil, where the
feeding roots are located. If applied wholly on the
surface of the soil, the tendency of the root is to go
to that point, or where the food is, and trees which
have the larger proportion of the feeding roots near
the surface are more liable to suffer from drought
than those which have them distributed at greater
depths in the soil. Hence, in the application of fer-
tilizers to orchards, particularly in the early life of
the trees, they should, as far as possible, be well
-worked into the soil, which may be readily accom-
plished by applying upon the surface before plowing.
The after-fertilization, if it seems desirable to leave
the orchard in sod, may be upon the surface, though
in that case the soluble fertilizers are preferable,
since they would rapidly descend, while the insoluble
would do so more slowly, or only as rapidly as they
became soluble.
THE FERTILIZATION OF APPLES AND PEARS
The necessity for the application of fertilizers in
the growing of apples and pears is largely due to
the fact that it is really a continuous cropping of the
same kind, and, therefore, more exhaustive than a
cropping which removes more plant-food in the same
s
990 FERTILIZERS
period of time. While upon good soils the trees may
be able to acquire sufficient food to mature maximum
crops for a considerable period, the life of the tree,
as well as the character of the fruitage, will be very
favorably influenced by the fertilization.
An experiment* bearing upon this point is very
instructive, as indicating the need of manures for
fruit trees, not only in reference to the amount
removed, but also in reference to the proportions of
the essential constituents required. This study shows
that the plant-food eontained in 20 crops of apples,
of 15 bushels per tree, and 35 trees per acre, and in
the leaves for the same period, amounts, in round
numbers,-to 1,337 pounds of nitrogen, 310 of phos-
phorie acid, and 1,895 of potash. These amounts of
plant-food are compared with the amounts that would
be removed by 20 years’ continuous cropping with
wheat, assuming an average yield of 15 bushels of
wheat per acre, and 7 pounds of straw to 3 bushels
of grain; viz., 660 pounds of nitrogen, 211 of phos-
phorie acid, and 324 of potash. By this comparison
it is shown that the 20 crops of- apples remove more
than twice as much nitrogen, half as much again of
phosphorie acid, and nearly three times as much pot-
ash as the 20 crops of wheat.
These results are valuable in indicating the rate of
soil exhaustion by apple-growing. It is to be remem-
bered, however, that the larger root development of
the tree would enable it to draw its nourishment from
* Cornell Exp. Sta., Bulletin No. 103, “Soil ‘Depletion in Respect to the
Care of Fruit Trees.”
THE NEED OF FERTILIZERS 291
a larger area of soil than is the case with wheat, and
thus probably permit of normal growth for a longer
period.
Too many are satisfied with short crops of medium
fruit, with off-years and with short-lived trees, largely
because they do not know that all of these conditions
may be improved by a proper feeding of the tree, and
that such feeding will usually result in a very largely
increased profit.
Statistics gathered in the state of New Jersey* show
that over 90 per cent of the commercial apple- growers
in the southern and central sections use fertilizers or
manures for their orchards, whereas, in the northern
section about 70 per cent use manures. In the northern
section the orchards are usually located upon soils of a
very high natural strength, and which are peculiarly
well adapted for the growing of fruits, while in the
central and southern sections, the soils in many sections
are of medium, if not of very low fertility. Hence,
while the larger proportion of the growers use fertili-
zers or manures upon the poor soils, a very considerable
number use manures for orchards located upon soils
which are regarded as of the best; yet all claim that it
is a paying practice.
There is also a difference in the time at which
manuring or fertilizing should begin. When the soil
is naturally good the fertilization need not begin with
the setting of the tree, as the food obtainable is usually
sufficient to provide for a good growth of leaf and
*Bulletin No. 119, New Jersey Experiment Station.
292 FERTILIZERS
wood, and in many cases maximum crops of fruit for a
number of years, though even here fertilization should
preferably begin as soon as large crops are produced,
whereas, on the lighter soils, fertilization should
begin when the tree is set.
The Amounts to be Applied
For these crops, either of the basic mixtures sug-
gested (p. 288) will provide a sufficient proportion of
nitrogen, except possibly upon the more sandy soil.
On light soils, the necessity for liberal fertilization with
nitrogen is frequently apparent, in which case it may
be applied in organic forms, preferably from materials
that do not decay too rapidly, as tankage, or wool waste,
and other waste nitrogenous materials, because they may
be obtained more cheaply, and because they furnish the
nitrogen quite as rapidly as is needed by the tree. In
many cases it is possible to obtain the necessary nitro-
gen from the growing of leguminous crops, as crimson
clover, though when these are used they should be
plowed down early in the spring, in order that their
erowth may not interfere with the growth of the tree.
If they are allowed to remain until mature, they ab-
sorb not only the food that may be necessary for the
erowth of tree and fruit, but the moisture also, and
thus they frequently injure rather than improve the
erop prospects.
On soils of good natural character, the fertilization
of apples and pears should begin as soon as the trees
reach the bearing period, and an annual application of
ABUNDANCE OF MINERALS NECHSSARY 293
400 pounds per acre of either formula 1 or 2 should
be made, preferably in early spring, and plowed in.
As they grow older and the yield of fruit is larger, the
amounts should be increased. While no definite rules
ean be laid down as to the most profitable amounts to
apply, the best growers find that it pays to use from
1,000 to 1,500 pounds annually of mixtures which
furnish practically the amounts and kinds of plant-
food contained in the formulas suggested. The profit
is found, not only in the larger yield, but in the
quality of the fruit and in the increased tendency
toward continuous crops, and in longer lfe of the
tree. On soils of medium character the fertilization
should begin earlier, and the amounts of the basic
fertilizer should be larger. In many eases, too, nitro-
gen, in addition to that contained in the basic formula,
should be added, the kind and form depending, per-
haps, upon the relative cost more than upon any other
one thing, the minimum amount to be 20 pounds per
acre, or an equivalent of 125 pounds of nitrate of
soda.
On poor soils, the necessity for fertilization is nat-
urally greater than for either of the others. In fact,
on these liberal fertilization—500 pounds per acre of
basic formula No. 2—should precede the setting of the
trees, and be continued annually. On these soils, too,
green manuring as a source of nitrogen can be prac-
ticed with safety for a longer period than in the pre-
ceding case. In the presence of an abundance of
minerals, the need for nitrogen is indicated by the
color of the foliage. If it lacks vigor and is yellow in
994 FERTILIZERS
the spring, rather than green, a dressing of from 100
to 150 pounds of nitrate of soda will supply the needs
to better advantage than any other form.
PEACHES
Peaches differ from apples and pears in respect to
fertilization, because the period of development of
the tree, preparatory to bearing, is shorter, and be-
eause the cropping is usually much more exhaustive.
Hence, the demands for added plant-food are propor-
tionately greater in the early life of the tree, and are
different, because of their more rapid growth. That
is, forms of nitrogen that are more available are pre-
ferred to the slowly available materials recommended
for apples and pears.
The Need of Fertilizers
The results of an experiment conducted by the
New Jersey Experiment Station* are interesting and
valuable, as bearing upon this point. They show the
value of fertilization, not only in increasing the yield
of crops, but in extending the period of life of the
trees, and in overcoming unfavorable crop conditions.
The soil upon which the experiment was conducted
possessed only medium fertility, good mechanical con-
dition, and was fairly representative of soils naturally
well adapted for peach-growing. The fertilized plots
received annually—
* Annual Reports of New Jersey Experiment Station, 1884-94.
THE NEW JERSEY EXPERIMENTS 295
DRANG PRG SOME 4 aw caprtes Xe we deh oe: 8 150 lbs.
Bone-black superphosphate. ...... 55) aa
Mitre GE PRIEAGH cs gas yh oe Be ns ee 150 ‘*
per acre, whereas the manured plot received manure
at the rate of 20 tons per acre.
The following tabular statement shows the results
obtained:
I, THE YIELD WITHOUT MANURE
Baskets
per acre
1884=1891, inclusive, 8 years, eps, ees ane tna Nees 65.7
1884-1895, . Pe a ek ty ace a ae igen tos ole 60.3
1887-1891, a (5 erop years), oe Le — toe LOD
1887-1893, ne é a yah eee
Il. THe YIELD WITH COMPLETE CHEMICAL MANURE
Baskets
; per acre
1884-1891, inclusive, 8 years, mene? ad your pire cieegiate, os 164.2
1884-1893, : I a SES ica Re a ae a en ae eke 183.4
1887-1891, ag (5 crop Ba ayerage Bee eee iy weeaes
1887-1893, a tte > at eed
II. THe YIELD WITH BARNYARD MANURE
Baskets
per acre
1884-1891, inclusive, 8 years, EreTaeY a your we Sh yr he near 169.5
1884-1893, ei 1 OR Sa Na aa MN Cale A aS ESAS Fe Y- 194.7
1887-1891, es (5 crop years), average per year .. . 271.3
1887-1893, rs fa Fe 5 = Ss). he
IV. THE RELATIVE YIELD IN AN UNFAVORABLE SEASON
Baskets
per acre
eter TeEITPEEREPIEB EMS ea SS eae AS ae Lee ahs: hale 10.9
Ere MRE IME MN Rareah Sect Ee ws a es Pa, oo Ey Re A ae ee et el mg 152.5
ToS Segal itl c/o ma pe oe aaann ede ee SEM Me atey SSE ey SMO US OL Same, oe 162.5
296 FERTILIZERS
“The first point of importance and value observed
is in reference to the number of crops that were
secured. On the unmanured land, the crops secured
after eight years were so small as to materially reduce
the average for the whole period, while for the ma-
nured land the average for the whole period was not
only not reduced, but very materially increased; that
is, the crops secured on these after the trees on the
unmanured land had practically ceased to bear were
greater proportionately than those secured previous
to that time. This was true both for the fertilized
and manured land.
“In the next place, it is shown that the yield was
very materially increased by the use of manures,
either in the form of artificial or natural supplies,
and the differences in yield derived from these two
forms are very slight, indicating that very much
smaller amounts of actual plant-food in quick-acting
forms were quite as useful as larger amounts of the
less available forms in which the food exists in
natural manure products.
“For the ten years, the fertilized plot received 250
pounds of nitrogen, 560 of phosphoric acid and 750 of
potash, while the yard manure plot received — assum-
ing the average composition of yard manure — 2,000
pounds of nitrogen, 2,000 of phosphoric acid and
1,600 of potash; yet with eight times as much
nitrogen, nearly four times as much phosphoric acid
and more than twice as much potash, the yield was
but 113 baskets greater, or an average of 11 baskets
per acre.
FERTILIZERS FOR GOOD AND POOR SOILS Y97
“In the third place, it is interesting to observe—
and it is a point of great importance—the effect of
an abundance of food in overcoming unfavorable
weather or seasonal conditions. The year 1889 was
extremely unfavorable, and the crop throughout the
state was small. In this experiment the unmanured
plot yielded at the rate of 10.9 baskets per acre,
while the manured and fertilized plots both showed a
yleld exceeding 150 baskets per acre. The manure
strengthened and stimulated the trees, and enabled
them to successfully resist such conditions as were
fatal to the crop on the unmanured land.
“This point is one that is seldom considered in
calculating the advantages to be derived from proper
manuring, though it is of extreme value, since the
expenses of cultivation, trimming, and interest on
investment are quite as great in one case as in
the other.” *
Methods of Fertilization
On soils of good natural character, the necessity
for fertilizing peaches is seldom apparent until after
the first or second year of growth. That is, good
soils will provide sufficient food for a normal develop-
ment of leaf and wood, and any additional fer-
tilization would have the tendeney to unduly increase
the tree growth. On medium and poor soils, the
setting of the trees should be preceded by a fer-
**Manuring Orchards.” Massachusetts Horticultural Society, 1896.
298 FERTILIZERS
tilization with one or the other of the basic mix-
tures (p. 288), on the better soils No. 2, and on the
poorer No. 1, at the rate of 400 to 600 pounds per
acre, which should be followed by the application of
the more soluble fertilizers immediately the trees begin
to bear. The need of nitrogen is often very marked,
and is shown by a lack of vigor of the tree. The
soluble nitrates have proved very valuable as a source
of this element, since from these the nitrogen may
be appropriated by the roots during the early season,
and which, if a sufficient abundance of the minerals
is present, enables a normal development of leaf and
branch. If the quick-acting nitrogenous fertilizers
are applied late, or if too large applications of the
slower-acting nitrogenous materials are applied early,
the tendency is to provide for a continuous feeding
on nitrogen, and thus encourage an undue develop-
ment of leaf and branch, which does not permit the
ripening of the wood before the beginning of winter.
Thus on these soils, in addition to an annual applica-
tion of the basic formula, from 100 to 150 pounds of
nitrate of soda, 200 pounds of acid phosphate and
100 of muriate of potash should be applied early in
the season and carefully worked into the soil.
For peach crops, too, green manuring with legumi-
nous crops should be earefully carried out, since
if too much nitrogen is added by this means, an
abnormal growth of wood is encouraged, and a late
ripening of the fruit occurs; and injury to the tree
may follow if the manuring crop is not used at the
proper time, as already indicated.
CAREFUL USE OF NITROGEN 299
Many orchardists use much larger amounts of fer-
tilizer than is here recommended, though if the sug-
gestions concerning the method of use are carried out,
the quantities named will be found sufficient to supply
all the needs of maximum crops.
PLUMS, CHERRIES AND APRICOTS
The fertilization of these fruits, when grown on
the different classes of soils, need not differ materially
from that recommended for peaches under the same
conditions, though cherries, particularly, require in
addition to the essential constituents, nitrogen, phos-
phorie acid and potash, a relatively greater supply
of lime, and this substance should be applied in
addition to the regular fertilization. Care should
also be exercised in the application of nitrogen, in
order to prevent a too great development of leaf and
branch. Unless these trees show a decided need for
nitrogen, a medium application of the second basic
formula (p. 288) will furnish sufficient for their needs.
CITROUS FRUITS
These products—the oranges, lemons, and the like—
belong to a distinct class of fruits, and the experience
already gained in their fertilization is such as to make
- applicable the suggestions concerning peaches, plums
and apricots. On the lighter sandy soils of Florida,
which are naturally well adapted for oranges, growers
have found potash to be a specially important element
|
- 800 FERTILIZERS
in manures. The nitrogen and phosphorie acid should
be accompanied by a larger proportion of potash than
is recommended for the stone fruits. Great care should
be exercised in the use of nitrogen, though in the ease
of these semi-tropical crops, the danger from immature
growth, as in the case of fruits for the more northern
climates, is not so marked.
SMALL FRUITS IN GENERAL
These crops do not differ from those already dis-
cussed in reference to their needs for liberal fertiliza-
tion, yet because of their different character of growth,
the method of fertilization should be somewhat dif-
ferent. They are, as a rule, crops which require a
shorter preparatory season, and have a shorter period
of bearing life. The strawberry, for example, does
not advantageously bear more than two crops without
re-setting, whereas the blackberry and raspberry may
range in life from four to eight years, and the goose-
berry and currant are relatively long-lived, provided
they are supplied with an abundance of food. In
respect to their general character, they correspond more
nearly with the vegetable crops than with the cereal
grains, in that they possess a relatively higher market
value and a lower fertility value than these, and the
period of growth and development of the fruit is much
shorter. Therefore, natural sources of plant-food may
be largely ignored in their growth, and the more quickly
available — particularly nitrogenous and phosphatic —
materials supplied.
AVAILABLE PLANT-FOOD RECOMMENDED 301
STRAWBERRIES
In the case of the strawberry, the preparatory
period of growth of the plant before bearing is but one
year, and the crop that may be obtained is largely
dependent upon the strength and vigor of plant which
has been acquired during this period. Hence, it is
desirable that the soil in which the plants are set should
be abundantly provided with the mineral elements,
particularly with soluble and available phosphoric acid;
hence an application of from 500 to 800 pounds per acre
of basic formula No. 1 (p. 288) is recommended. The
nitrogen should also be in quickly available forms, and
should be supplied in sufficient quantities at time of
setting the plant to enable it to mature, and thus to
withstand the rigors of winter. Hence, an additional
application of 100 pounds of dried blood, or its equiva-
lent in nitrate of soda or ammonia, is advisable, par-
ticularly on soils not previously well enriched with
organic nitrogenous matter. In the spring of the sea-
son during which the first crop is harvested, an appli-
eation of a quick-acting fertilizer rich in nitrogen is
desirable, since it not only provides for an early and
strong growth of plant, but a better setting of fruit, if
other conditions are favorable; and frequently, with a
full setting, top-dressings with nitrate of soda are
useful, in order to insure the full development of the
crop. Many growers, therefore, who have supplied the
soil liberally with minerals and nitrogen, both at time
of setting the plants and in the following spring, make
top-dressings of nitrate of soda (about 100 pounds per
302 FERTILIZERS
acre), preferably after the plant has blossomed, in
order to insure a sufficiency of this element. This
should be applied at this time rather than later in the
season, since later applications have a tendency to
cause a soft growth of fruit, and thus injure shipping
qualities.
RASPBERRIES AND BLACKBERRIES
Raspberries and blackberries also require a soil
well enriched with the mineral elements, which insure
an abundant and strong growth of canes. The need
for nitrogen, while apparent, is less marked than in
the case of the strawberries, and the slower-acting
forms serve a good purpose, provided they are not
applied in too great quantities, so as to encourage a late
growth of plant, which does not fully mature. The
main object is to obtain strong, well-ripened canes,
and this can be accomplished with the slowly avail-
able nitrogenous substances, provided an abundance
of the minerals is present. An annual application
in spring of 500 pounds per acre of basic formula
No. 2 (p. 288) will furnish sufficient food on soils of
good character, though on lighter soils additional
nitrogen should be supplied, preferably in forms not
too active. The practice of applying quick-acting
nitrogen early in the spring, after plants have blos-
somed, has been followed with great success, particu-
larly upon the lighter soils, as it encourages a more
complete development of fruit, though it should be
used with caution, since the fruit canes of both the
FERTILIZE FOR FRUIT, NOT WOOD 303
present year and those which provide the plant for
the next year naturally grow in the same bed, and
the young canes may not mature properly if too
heavy applications of nitrogen are made.
CURRANTS AND GOOSEBERRIES
These are crops which, under average conditions,
are seldom heavily fertilized, though fertilizing is
usually followed with great profit. They are less
likely to need nitrogen than the other crops men-
tioned, and a too heavy fertilization with this element
has a tendency to encourage the development of mil-
dew, the disease so common to these crops. In com-
mon with the other crops mentioned, they should be
abundantly supplied with the minerals, phosphoric
acid and potash, and the basic formula already rec-
ommended (p. 288) may be used in all cases with
profit at the rate of 500 to 1,000 pounds per acre.
The additional nitrogen needed may be provided by
the slow-acting materials. Many growers find such
waste products as wool and hair of great advantage
in the growing of these crops.
GRAPES
Grapes are more exhaustive as a crop than most of
the fruit crops, largely because of the larger total crop
harvested, and the special need is for phosphoric acid
and potash. These elements may be supplied by the
basic formula (p. 288), and very liberal dressings are
304 FERTILIZERS
recommended,—from 1,000 to 2,000 pounds per acre
annually,—after the bearing period begins. On
light soils, an annual spring dressing of nitrate of
soda, at the rate of 200 pounds per acre, is also
desirable, in order to encourage rapid and large
early growth of leaf and vine, though this dressing
may be omitted if the growth of clover as a green
manure is practicable. The latter, however, as when
used in connection with the other fruits mentioned,
should not be allowed to mature, but rather be
plowed down early in the season.
The main point in the fertilization of all fruits is
to provide an abundance of the mineral elements, and
to give particular attention to fertilization with nitrog-
enous materials. It must be remembered that it is
the fruit, not the wood, that constitutes the crop,
and that all the energies should be directed toward
the development of such a tree or vine as will best
contribute toward this end.
CHAPTER XV
FERTILIZERS FOR VARIOUS SPECIAL CROPS
IN ADDITION to the generally familiar crops already
deseribed, there are certain special ones, not distinct
from the others because they are of less importance,
but rather because they are only grown in certain
localities.
COTTON
Among these special crops, cotton takes first rank,
because it is one of the leading crops of the country,
occupying wide areas, and exercising fully as great
an influence upon our agricultural prosperity as any
other of our American staples.
The climate suitable for the growing of cotton is
confined to about one-quarter of the area of the coun-
try, and in this area it occupies a more important
position than any other crop grown there.
In the earlier history of its cultivation, the methods
employed were not such as to encourage the largest
yield. In the first place, it was grown on the poorer
soils rather than the more fertile, and after it had been
grown consecutively upon the same lands for a number
of years, and thus rapidly exhausting them, the
planter, instead of attempting to improve the lands,
T (305)
306 FERTILIZERS
either by better methods of culture or by the use of
manures, extended the areas under cultivation. After
the civil war, when it became still more necessary to
change methods, fertilizers were looked to as the main
reliance, rather than the improvement of the character
of the soil, either by judicious rotation or by manur-
ing. The results secured from the use of fertilizers at
this time were so generally satisfactory that their large
and indiscriminate use was encouraged, and this, with-
out proper attempts at the improvement of the soil in
other respects, hastened the time when such use did not
give profitable returns. The very great importance of
the crop to the agriculture of the leading cotton states,
and the necessity of better methods of culture, were so
fully appreciated that a scientific study of the crop was
then entered upon, and the states largely interested
planned, through the aid of their colleges and ex-
periment stations, a wide series of experiments, which
were directed toward the solution of the problems
connected with the feeding of the plant. The results of
these experiments have been fruitful of such valuable
information as to warrant practical and specific sug-
gestions which have a wide application, and which, if
followed, will result in the improvement of the soil and
in the economical increase in crop.
As already stated, the cotton crop is not an ex-
haustive one in one sense, though the methods of
practice used in its growth have been wasteful, and
thus have given rise to that belief. That is, a large
crop of cotton does not remove from the soil a very
considerable amount of the fertilizer constituents.
IMPORTANCE OF PHOSPHORIC ACID BUT
The following amounts are contained in a crop yield-
ing 300 pounds of lint per acre :*
2 UE, Sr ii EA Pir ne i aa 46 lbs.
RONNSHISEIS RAG Fe is oe a) ee RT 12 lbs.
RIED ers) SEN aT aia tacit ye tie BR
Fertilizers for Cotton
In regard to its need for fertilizing, cotton may be
classed with the cereals rather than with the crops al-
ready discussed; and like the cereals, its best growth
is attained when properly introduced into a rotation
with other crops, and the annual food supply arranged
in such a manner as to contribute to the larger yield of
the immediate crop, as well as to furnish an unused
residue which will provide for an increase in the yield
of the succeeding ones. Of the constituents, phos-
phorie acid seems to exercise a greater influence upon
the growth and development of the cotton plant than
any other element, notwithstanding the fact that
smaller amounts are contained in it than of either
nitrogen or potash. That is, it appears that the plant
must have an abundance of available phosphoric acid
at its command in order that the other constituents
necessary for a full crop may be freely absorbed, though
on the soils adapted for the crop, which naturally vary
widely both in their general and special physical char-
acteristics, but are poor in the fertility elements, both
nitrogen and potash must be applied, in order that
maximum crops may be obtained.
*Parmers’ Bulletin No. 14, Department of Agriculture.
308 FERTILIZERS
On the whole, therefore, though the “intensive”
system is not generally practiced, fertilizers furnishing
all of the constituents are superior to those which fur-
nish but one or two; -yet when proper rotations are —
practiced and leguminous crops are grown for the pur-
pose of improving the physical character of the soil, as
well as increasing its content of nitrogen, the percent-
age of this element introduced into the fertilizer may
be very largely reduced.
The conclusions that have been arrived at by the
experiments conducted in the various states have been
very fully set forth in various publications,* and the
following statements drawn from these indicate what
are believed to be the advantages derived from the right
use of fertilizers, and the best methods to be observed:
“The cotton plant responds promptly, liberally and |
profitably to judicious fertilization. The maturation
of the crop may be hastened, and the period of
growth from germination to fruiting may be so short-
ened as to increase the climatic area in which it may
be profitably grown. It should be assigned to a
place in a rotation system. One of small grain, corn
(with peas) and cotton, is well suited for the con-
ditions prevailing in the cotton belt, and, as with
other crops, the results derived from the use of
fertilizers for this crop are much enhanced by the
proper preparation of the soil. It pays to bring
* Farmers’ Bulletins, Nos. 14 and 48, Department of Agriculture. Office of
Experiment Stations, Bulletin No. 33, Department of Agriculture. Various
bulletins issued by the Georgia, South Carolina and Louisiana Experiment
Stations.
FORMULAS FOR COTTON 309
up the cotton lands by mechanical treatment,
and especially by introducing organic matter. The
renovating crops, especially the cow pea, are very
profitably employed as adjuncts to the fertilization
of the crop itself. On the majority of soils, too, it is
advisable, and more generally proves profitable, to use
a complete fertilizer, rather than one containing one
or two of the constituents; and of the forms of nitro-
gen, organic (vegetable and animal) is best suited
to the cotton, if one form alone be used, although
nitrate of soda is probably nearly, if not quite, of
equal value. The relative advantages of various pro-
portions of the different forms have, however, not yet
been fully determined; hence the use of a mixture
of the best is a safe plan, the proportions to be
determined by their relative cost. In the case of
phosphoric acid, superphosphate is to be preferred to
to materials of an organic or mineral nature, which are
not immediately available. Of the potash salts, no
particular difference is observed in the use of the
different forms. The form to be secured is to be
based upon the price of the different forms.”
Formulas for Cotton Fertilizers
While the most judicious proportions of soluble
phosphoric acid, of potash and of nitrogen in a com-
plete fertilizer cannot be said to have been determined
with entire accuracy, the carefully conducted experi-
ments of both the Georgia and South Carolina sta-
tions indicate that for general use 1 part of nitrogen,
310 FERTILIZERS
1 of potash, and 22% or 3 of phosphoric acid in-
dicate the best proportions. The amount of fer-
tilizer that may be profitably used very naturally
varies widely, though medium rather than very large
dressings are recommended, not so much because the
plant under good soil conditions could not appropriate
and use to advantage large amounts, but because on
the whole, soils used for cotton are peculiarly lacking
in those qualities which enable the proper distribu-
tion and appropriation of the larger quantity. For
those soils, then, the amounts per acre indicated by
the Georgia Experiment Station are, annually —
INFEVOROM 2a hod ct, a saan Be eee 20 Ibs.
Available phosphoric acid. ....... 70: 3°
POTS Bc go hearts aay 9's eee cas ats GL 20°.
The South Carolina Experiment Station recom-
mends an application per acre of —
NRG REN:. Pc. id an a ase say ake we 20 lbs.
Available phosphorie;seid .-.-. . 2+: <;% 50k nc
1g aa Arne Neg Not a RSG PE ats 10h are
or, as suggested by the Georgia Experiment Station,
perhaps a fertilizer containing —
INDGROSEM SS aos We eee) whe nal a eae 3%
Phosphoric acid: (soluble)... 2 oc ee ae 9 %
Potash $2.2 hk 2 eS eS eee 3%
applied at the rate of 700 pounds per acre, would be
approximately the best amounts to use under ordinary
circumstances.
ADVANTAGES OF HOME MIXTURES ke
Method of Application
The fertilizer should be applied in the drill at the
time of planting, and at the depth of not more than
three inches, and well mixed with the soil. In
most eases it is best to apply all of the fertilizer in
one application rather than in fractional applications,
though with lands in superior condition profitable
applications may be made again at the second plow-
ing. Owing to the nearness of the cotton belt to
the supplies of superphosphate, and to the cheap sup-
plies of cotton-seed meal, the only fertilizer neces-
sary to import is potash. Hence it has become a
practice in most sections for the planter to make his
own formulas, using his own supplies of phosphoric
acid and nitrogen; and home mixtures, made up of
acid phosphate, cotton-seed meal and muriate of
potash, or kainit, are largely used to supply the
demands. The following formula is an example of a
good mixture :
CIA POS PEALG: os oe Kw sl es oe OS 1,200 lbs.
Upison-seed meal... 9. 2s . 6 6 sss 0 i
matcher oul ie boyy Oo oP le SP ake 200° **
The formula containing —
EL RECOM Beep cd ee eS yh ca pie ge wel we a eee 3%
PGB OTIO: RCO = se ahora. at oe ei aes 9%
eat ced Fay GAN SAG ust ah od (2% ete a the 3 %
is also recommended, since an application of 700
pounds per acre will furnish the amounts and propor-
tions of the elements indicated as the maximum by
312 FERTILIZERS
the Georgia station. This formula is also well suited
for corn, if introduced into a rotation as previously
suggested.
TOBACCO
Tobacco is another special crop grown only in cer-
tain localities, favored either by reason of climate or
character of soil, or both. It is, however, a_ very
important crop in this country, and one which requires
very careful attention in reference to the amounts and
kinds of fertilizers applied, because the fertilization
exercises an influence upon both the yield and quality
of the crop. It is an exhaustive crop, drawing heavily
upon both nitrogen and potash. <A crop yielding 1,000
pounds of leaf per acre will contain, in round numbers,
67 pounds of nitrogen, 9 of phosphoric acid and 85 of
potash: amounts equivalent in nitrogen to over 400
pounds of nitrate of soda, of phosphoric acid equiva-
lent to 75 pounds of acid phosphate, and of potash
equivalent to 170 pounds of muriate of potash. It is
a fact, too, that tobacco of the best quality, or that
best suited for cigar wrappers, can be grown to ad-
vantage only on light, sandy soils,—those not natur-
ally well supplied with the fertilizing constituents.
Thus, if large crops are to be secured, the soil must
receive liberal supplies of food from artificial sources.
The Influence of Fertilizers on the Quality of
the Orop
A point of great importance in the fertilizing of
tobacco, is the influence of the constituents applied
FERTILIZERS INFLUENCE QUALITY 313
on the marketable quality of the crop, as for certain
purposes, especially for the manufacture of cigars and
cigarettes, the tobacco must possess peculiar charac-
teristics in order to bring the highest price in the
market. In other words, in the growing of this crop,
as is the case in many others, both the yield and
quality must be taken into consideration, and frequently
the latter point is of quite as much importance as the
former, though a reasonable yield must be secured
before the influence of quality is of practical signifi-
eance. The quality of the leaf is believed to be
influenced chiefly by the constituent potash, though
many growers object to the use of various nitrogenous
and phosphatic materials, believing that they, too,
exercise a decidedly unfavorable influence upon the
quality of the leaf. Careful experiments, however, do
not justify many of the opinions of growers and dealers
regarding the effect of the different materials upon the
quality of wrapper tobacco.
The main points, therefore, in the fertilizing of
tobacco, are to see to it that a sufficient quantity of
plant-food is applied in order to secure the largest
possible yield consistent with quality, and second, to
avoid the use of such constituents as are positively
injurious.
The Conclusions from Connecticut Experiments
Experiments in the application of fertilizers to to-
baeco have been earried out at the Connecticut Exper-
iment Station with great care and skill for a number
314 FERTILIZERS
of consecutive years.* They lead to the conclusion
that “there is no ‘best’ tobacco fertilizer, or ‘best’
formula for all seasons, even on the same soil. A
formula or a form of plant-food which in one season
gives the leaf a somewhat better quality than any
other, may, perhaps the next year and on the same
soil, prove inferior to others, for reasons which can
only be surmised.
“Nevertheless, by comparing the effects of these
fertilizers for a term of years, it appears that certain
ones are, on the whole and generally speaking, more
likely to impart a perfectly satisfactory quality to the
leaf than certain others.
“Tt is doubtless true of tobacco, as of other crops,
that the liberal but not greatly excessive supply of
readily available plant-food yearly required to insure a
paying crop may be given in a variety of forms with
equally good results, on the average of one season with
another, and that, indeed, occasional changes in the
form of nitrogen and potash supplied may be a distinct
advantage, avoiding always any considerable quantity
of those things, as chlorin, and sulfuric or other free
acids, which experience has shown may damage the
leaf.”
These conclusions in regard to the kind and quantity
of fertilizing constituents required for the growing of
tobacco of good quality confirm those arrived at by
experiments elsewhere, and the suggestions made are
sufficiently definite to guide in the use of fertilizers
*Connecticut Agr. Exper. Sta., Annual Report, 1897, Part IV., page 255.
DESIRABLE FORMS 515
for this crop. In brief, therefore, the tobacco crop
must be provided with an abundance of all of the fer-
tilizer elements derived from readily available forms,
and free from those constituents known to exercise an
unfavorable influence upon the quality of the product,
in order that satisfactory yields of good quality may be
secured.
Form of the Constituents
It has not been shown that one form of nitrogen
is superior to another under all circumstances, or in
other words, that one form of nitrogen,—as, for
example, ammonia or nitrate, or any particular form
of organic nitrogen, vegetable or animal,—is superior
to all others, but rather that any or all of the good
forms may be used in a mixture, provided a sufficient
abundance is present to insure a maximum jield,
though not so large an amount in excess of the
minerals as to encourage a rank, coarse growth. The
phosphorie acid should be in available forms, and if
in these forms, must naturally be drawn largely from
superphosphates. The potash should in all cases be
drawn from sources free from chlorids. <A fertilizer,
therefore, which contains the nitrogen, either in good
organic forms, as cotton-seed meal or blood, or a mix-
ture of these organic forms with ammonia or nitrate
in not too large amounts, which contains the phos-
phorie acid in a soluble form, and potash derived
from products free from chlorids,—as from high-grade
sulfate, or from a carbonate, or from cotton-hull
316 FERTILIZERS
ashes, if these are obtainable,—may be regarded as
well adapted for the crop.
Amounts to Apply
An annual dressing which will furnish 100 pounds
of nitrogen, 75 of phosphoric acid and 150 of potash
per acre may be regarded as a minimum for soils of
medium quality. On lighter soils heavier applications
should be made, and on soils previously well enriched
with the fertilizer constituents, the dressing may be
somewhat less. It must be remembered, however, that
it is not economical, from the standpoint of either
yleld or quality, to be too sparing in the applica-
tion of fertilizers, because the plant requires large
amounts of both nitrogen and potash, and because it
is essential that the plant should have a reasonable
excess of these at its command, in order to overcome
as far as possible any unfavorable seasonal conditions
that may occur.
In the Connecticut experiments already referred to,
amounts greatly in excess of those suggested have
been used with advantage. In Kentucky and Vir-
ginia, on soils naturally richer, smaller amounts have
given quite as good results. It is likely, however,
that upon the very light soils of certain of the
states in which tobacco of high quality is grown,
notably Florida, considerably increased amounts may
be used with profit.
As sources of at least part of the nitrogen and
potash in the southern states particularly, cotton-
FERTILIZERS FOR SUGAR-CANE 317
seed meal and cotton-hull ashes are recommended,
because readily obtainable. These forms have been
found to be good, and they may be obtained as
cheaply as other forms as well as more conveniently.
SUGAR-CANE
Another special crop, confined largely to one state,
Louisiana, is sugar-cane, and perhaps no other one
crop has in this country received such careful study
in reference to its needs for plant-food. The Sugar
Experiment Station of that state has for twelve years
conducted a series of systematic experiments designed
to answer the questions as to what the needs are
for nitrogen, phosphoric acid and potash; and the
results of this work thus far secured furnish sugges-
tions in reference to fertilization, which will, if care-
fully followed, undoubtedly result in the production
of better crops than are grown under present systems.
Fertilizers are clearly needed, and their right use is a
profitable practice, though, as stated by Doctor Stubbs,
“many ascribe the failure from their use to the worth-
lessness of the fertilizer, when it should be ascribed
to some defection of the soil, rendering it incapable
of appropriating the applied fertilizer.”
The chief conclusions in reference to fertilizers
for sugar-cane in Louisiana, so clearly set forth by
Doctor Stubbs in this report,* are here summarized,
as it is believed that the underlying principles are
*“Sugar-Cane,” Vol. I, Sugar Experiment Station, Audubon Park, New
Orleans, La.
318 FERTILIZERS
applicable elsewhere, though naturally their use must
be modified te suit individual cases.
The Needs of the Plant as Indicated by the
Louisiana Experiments
“An examination of the cane plant shows that a
erop of 30 tons will remove, in round numbers, 102
pounds of nitrogen, 45 of phosphoric acid and 65 of
potash. It is, therefore, a relatively exhaustive crop,
and unless the physical conditions are perfect, even
good soils should receive considerable dressings of the
constituents, if the fertility is to be maintained.
“The results secured thus far in the experiments
referred to demonstrate that the soil needs nitrogen
and phosphoric acid particularly, in order to grow
eane successfully, while thus far, no results of any
character, either in the increased sugar content or
tonnage per acre, have been visible from the use
of any form of potash upon the alluvial lands of
the lower Mississippi. Several forms. of potash,
notably the carbonate, and ashes of cotton-seed hulls,
have rather decreased the yield of cane and injured
the physical qualities of the soil by causing it
to ‘run together.’
“In reference to the form and amount of nitro-
gen, it has been shown that: sulfate of ammonia
gives slightly better results than any other form,
though its higher cost gives no advantage over those
costing less, while cotton-seed meal comes next, fol-
lowed by dried blood and nitrate of soda. In refer-
LOUISIANA EXPERIMENTS 319
ence to the amount of nitrogen to be applied, it is
shown that not less than twenty-four pounds nor more
than forty-eight pounds per acre should be applied.
Naturally, different soils and different kinds of
cane would vary in their requirements for this
element, and the amount needed would also be in-
fluenced by the method of growing the crop: whether
upon ‘succession’ land—that is, upon soils upon which
a crop of stubble cane has just been taken off, and
which has been in cane for a number of years with-
out the intervention of a leguminous crop between to
restore the nitrogen—or whether upon pea-vine land,
upon which the plant cane is grown the first year,
stubble cane the second, and corn and cow peas the
third year. This system of rotation, which intro-
duces a leguminous crop into it, not only improves
the physical quality of the soil, but enables a con-
siderable accumulation of nitrogen, frequently over
one hundred pounds per acre. The pea-vine lands,
put in plant cane on account of their excellent physi-
eal condition, not only yield up readily the nitrogen
stored up by the pea, but can also assimilate larger
quantities of plant-food applied as fertilizer. Hence,
such cane usually makes large crops. Since nitrogen
is the chief ingredient taken from the soil by a crop
of cane, it follows that with each successive crop of
cane grown on the land without the interjection
of the leguminous nitrogen there arises an increased
demand for nitrogen. Hence, stubble cane requires
larger quantities than plant cane, and the older the
stubble, the larger its requirements for this element.”
320 FERVUILIZERS
In reference to phosphoric acid, the results so far
indicate positively the value of this element in fer-
tilizers for sugar-cane on these soils, but the demand
for this ingredient is small in comparison to that for
nitrogen, 36 pounds per acre being ample for the crop.
The results further show that the soluble forms of
phosphoric acid are preferred. Inasmuch as the legu-
minous crop does not add to the store of phosphoric
acid in the soil, it is equally needed by both plant and
stubble cane.
While potash has not been shown to be needed on
the land upon which the experiments were conducted,
because of the abundance of potash contained in the
soil, after continuous cropping of these and on lighter
soils this element should be included in the fertilizer.
The Application of Fertilizers
For plant cane, a small quantity of readily available
fertilizer directly under and near the cane is highly
beneficial, as it provides food also for the sucker,
which, with food at hand, is greatly aided in develop-
ing a healthy sucker, and thus the entire plant is given
a vigorous send-off in youth. It is necessary, to
give a good start to a young plant, to withhold manures
until a stand is secured, though when cane is planted
during the fall and winter, as it is in Louisiana, the
danger of loss by leaching must be reckoned upon, and
the exact amounts to be applied at that time regulated
by the judgment of the planter. Usually the more
perfect the incorporation of a manure in the soil the
PROPER APPLICATION B21
better the results to be expected, but in this ease it
should be deposited in a drill and well mixed with the
soil. In the spring, after the cane is closely off-barred,
the fertilizer, if not applied at planting, should be
scattered on both sides of the plant from the center of
the row to the off-barred furrow. Hence, in reversing
the furrow, the manure is covered, and subsequent eulti-
vation will mix the latter with the soil. If the cane has
received the first application at planting, the second one
should be given in May, on both sides of the row.
The stubble cane should not be fertilized very long
before each sprout has sent out its own rootlets, since
prior to this no good could be accomplished, and there
would be a waste of manure.
MISCELLANEOUS CROPS
Other crops of importance for which the need of
fertilizers is frequently apparent include sorghum,
buckwheat, peanuts, roses and herbaceous plants,
lawns, grasses, and plant-house vegetables. These
are, of course, similar to those already described,
since their best development requires that they shall
be well supplied with the fertilizing constituents,
nitrogen, phosphoric acid and potash, though their
special needs in this respect have not been so fully
investigated as the other crops dealt with in this
chapter. The discussion of their requirements is,
therefore, necessarily brief, and the suggestions made
are of a general rather than a special character, though
they may serve as a safe guide.
U
O22 FERTILIZERS
Sorghum
Sorghum is grown both for forage and for sugar,
and its fertilization should be discussed from these two
standpoints. If grown for forage, the fertilization
should be more liberal and of a different character
than if for sugar, as the object is the largest yield of
succulent food rather than the highest yield of sugar,
and the yield of sugar is not always consistent with the
highest yield of cane. For forage, therefore, the ferti-
lizer recommended for maize forage (p. 242) is well
adapted for sorghum on soils in a good state of fertility,
though since the plant is very slow to start, its early
growth is stimulated if a larger amount of readily
available nitrogen is used than is desirable for corn,
particularly on soils of medium fertility, and which
have not been previously well fertilized. If grown for
sugar, too much nitrogen must be avoided, since an
excess of this element in the fertilizer causes an im-
perfect ripening, and consequently a higher percent-
age of non-crystallizable sugar in the cane; though
if quickly available forms are used, as nitrate, am-
monia, or dried blood, which may be absorbed by the
plant early in the season, a larger amount may be
applied with safety than if the poorer forms are used.
Of the three constituents, potash in the form of
muriate seems to be the one exercising the greatest
influence upon the yield of sugar, hence it should
always be introduced in considerable amounts in fer-
tilizers for sorghum.* A fertilizer furnishing 20
*Report for 1886, New Jersey Agricultural Experiment Station.
BUCKWHEAT 323
pounds of nitrogen, 35 of phosphoric acid and 60 of
potash per acre will meet the needs on average soils.
Buckwheat
Buckwheat is frequently grown upon the poorer
soils of the farm. It is a crop well adapted to moun-
tain lands, and as a preparatory crop in the breaking
of new lands. It has not been carefully studied in
reference to its needs for plant-food, though phosphoric
acid seems to be the constituent more particularly
required than the others. Its need of nitrogen is
marked, yet because its entire growth and development
are made during the months of July and August, when
conditions are most favorable for soil activities, heavy
nitrogenous fertilization is not to be recommended,
except when grown on very light soils, or those defi-
cient in vegetable matter. The moderate use of fer-
tilizers rich in minerals, and which contain nitrogen in
quickly available forms, result favorably, not only in
increasing the yield, but assist materially in maturing
the crop, a matter of great importance. A fertilization
with 25 pounds per acre each of phosphoric acid and
potash and 10 of nitrogen may be regarded as a good
one for soils of medium character.
Peanut
The peanut is a leguminous plant, and, like others
of this family, is not specifically benefited by nitrogen,
but responds readily to liberal dressings of phosphoric
394 FERTILIZERS
acid and potash. The fertilization suggested for green
manure crops, namely, a mixture of three parts acid
phosphate and one part muriate of potash, or equal
parts of acid phosphate and kainit, may be used for
this crop with great advantage. The applications, if
frequently made, need not exceed 300 to 400 pounds
per acre. Like other leguminous crops, it is specifically
benefited by lime, medium dressings of which (20
bushels per acre) should be made at least once in four
years. In the districts in which this crop is success-
fully grown, lime marls are frequently obtainable at
slight expense, and may be used with great advantage.
Roses, and Other Flowering Plants
In the growing of roses.and other herbaceous
plants, of which the flowers constitute the crop, great
eare is usually taken in the preparation of the soil,
and natural soils are seldom used. Notwithstanding
the richness of the prepared soils, the crops are bene-
fited by the addition of commercial fertilizers, partic-
ularly those phosphatic in their nature. Ground bone
is especially useful, since it furnishes both nitrogen
and phosphoric acid in slowly available forms, and
usually sufficient nitrogen to meet the needs of the
plant, as excessive quantities of this element cause a
too vigorous and rank growth of foliage, which is
not accompanied by profuse flowering. A good mix- |
ture for the prepared soils, therefore, may consist
of four parts of ground bone and one part of mu-
riate of potash, which may be applied at the rate of
FLOWERS AND LAWNS 325
four pounds per square rod of area, and well worked
into the soil previous to setting the plants. The after-
’ fertilization may contain a larger portion of the sol-
uble phosphoric acid, which is more readily distrib-
uted. The need for nitrogen is indicated by a yel-
low, rather than a bright green color in the foliage.
Nitrogen may be supplied by light dressings (% to 1
pound per square rod) of the active forms of this
element, preferably nitrate of soda, because of its ready
distribution. In the preparation of soils for these
plants in the house, the mixture may be applied at the
rate of 2 pounds for every 100 square feet of surface,
the after application to consist of the more soluble
forms as recommended for the hardy plants. An even
mixture of nitrate of soda and acid phosphate may be
used at the rate of one pound for every 100 square feet
of surface once in two weeks, if the plants do not
show vigorous growth.
Lawn Grasses
The fertilization of lawns is also important in a
sense, because proper fertilizing obviates the necessity
of the home manures, which, although excellent as
sources of the constituents, are frequently offensive.
The use of manure also involves considerable labor,
both in the application and the consequent removal
of the coarse part in the spring, besides resulting in
the introduction of weed seeds. In the preparation
of the soil for a lawn, it must be supplied with an
abundance of all of the necessary fertilizer ingredients
previous to seeding, and of these phosphoric acid and
326 FERTILIZERS
nitrogen are especially important. Too great an ex-
cess of potash encourages the development of the
clovers rather than the grasses. This preparatory*
fertilizer may contain the more slowly available forms
of nitrogen and phosphoric acid. Ground bone is an
excellent source of these elements, and a mixture of
five parts of ground bone and one of muriate of pot-—
ash makes an excellent dressing. This may be ap-
plied at the rate of five pounds per square rod, and
thoroughly worked into the soil. The after-fertiliza-
tion may consist chiefly of nitrogen, preferably as a
nitrate, since its ready solubility permits of its free
penetration into the lower layers, which encourages
a deeper root system, and thus greater resistance
to drought.
The top-dressings with nitrate of soda should con-
sist of light fractional dressings, rather than of large
amounts at one time. One-half pound per square
rod, twice or thrice during the season—the first as
soon as the grass is well started in the spring, and
preferably immediately preceding a rain—vwill, if the
land has been previously well prepared, be sufficient.
To facilitate the distribution of the nitrate, as well as
to supply a sufficient abundance of phosphoric acid,
it may be mixed with equal parts of ground bone.
Forcing-house Crops
A rich garden loam, to which a considerable pro-
portion of stable manure—one-third to one-half the
bulk—has been added, is the usual type of soils
VEGETABLES UNDER GLASS Set
for such crops as tomatoes, lettuce, radishes and
cucumbers under glass. The addition of fertilizers
to these is seldom advisable. It has been demon-
strated, however, that such mixtures are not essential,
and that the crops may be profitably and successfully
erown in mediums which contain no plant-food,* if
supplied with an abundance in available forms from
artificial sources. In the absence of good manure,
which is the chief expense, a reasonably fertile loamy
soil may be used for filling the beds, in which at the
time of filling may be mixed, for each 100 square feet
of surface, one-half pound of nitrate of soda, one
pound of acid phosphate, one pound of ground bone,
and one-half pound of muriate of potash. This appli-
eation will be sufficient to supply the needs of the
plants for food until growth is well started, after
which they should be fertilized at least once each week
with one-quarter of a pound of nitrate of soda for
every 100 square feet of surface area, and with the
mineral fertilizers at the rate of one pound of acid
phosphate and one-half pound of muriate of potash
every two weeks. These may be applied in solution,
or evenly distributed over the surface of the soil, and
worked in before watering. The amounts to apply
should always be governed by the judgment of the
grower. There is less danger from the application
of too much, if properly used, than is commonly
supposed.
* Connecticut State Experiment Station Reports for 1895, 1896 and 1897.
INDEX
Actual potash. See potash.
Agricultural salt, 117.
Agricultural value of a fertilizer,
measured by value of increased crop
produced, 152, and availability of its
constituents, 153; distinct from com-
mercial value, 153.
Alfalfa, character of its growth, 252;
its fertility content, 253; fertiliza-
tion, 253.
Ammonia, its formation in the soil,
50; a better form than organic nitro-
gen, 50; its commercial form, 50.
See also sulfate of ammonia.
Ammonite, its composition, 41; how
obtained, 42.
Analysis of fertilizers, how to inter-
pret, 149; indicates whether fertilizer
is high or low-grade, 149; does not
always show the source of the ele-
ments, 149.
Animal matter.
Apatite, 69.
Apples, soil-exhaustion from growing
290; fertilization, 291-3; New York
(Cornell) experiments, 290.
Apricots, fertilization, 299.
Artificial fertilizers, history of their
use, 28; need of, 30; made necessary
by increase in cost of labor, 30; by
demands for special crops, 32; from
inadequacy of farm manures, 33; by
growing importance of fruit-growing,
34; will it pay to use them, 35; rea-
sons for their unprofitable use, 36.
Artificial fertilizer cartridges, 187.
Ashes. See coal, cotton-hull, lime-
kiln, tan-bark and wood ashes.
See ammonite.
Asparagus, character of its growth,
264; conditions govering its sale,
265; salt as a fertilizer for, 266; fer-
tilization, 266-8.
Availability of fertilizers. See under
different fertilizing materials.
Azotin, 41, :
Barley, substitution of, for oats in
rotation, 207.
Barley and peas, fertilization, 248.
Basic slag, 70,
Bat guano. See guano. [bean.
Beans, fertilization, 270. See also soy
Beets, character of growth, 270; ferti-
lization, 271. See also fodder and
sugar beets.
Berries, ef, fruit crops and small fruits.
Blackberries, fertilization, 302.
Blood, dried, its characteristics, 40;
how obtained, 40; red, 40; black,
41; its composition, 41; the avail-
ability of its nitrogen, 55.
Bone-ash, how obtained, 66; its compo-
sition, 66.
Bone-black, how obtained, 65; its com-
position, 66.
Bone, dissolved. Seesuperphosphates.
Bone-meal, variations in its composi-
tions, 60; meaning of fine bone, 61;
its best use for soil-improvement
and slow-growing crops, 63, 76; its
nitrogen availability, 55; its phos-
phorie acid availability, 75; its phos-
phate more useful than that derived
from mineral sources, 66, 73.
Bone meal, raw, 60; its composition,
61; objections to its use, 61.
(329)
330
Bone meal, steamed, 61; its advan-
tages, 62; its composition, 62.
Bone phosphate, how to convert into
phosphoric acid, 134. See also phos-
phate.
Bone tankage, its agricultural value,
64; its composition, 63.
Brussels sprouts, character of its
growth, 272; fertilization, 273.
Buckwheat, fertilization, 323; as green
manure, 122.
Cabbage, character of its growth, 272;
fertilization, 273.
Canadian apatite, 69.
Carrots, fertilization, 258.
Castor pomace, its composition and
source, 47; the availability of its
phosphoric acid, 65.
Cauliflower, character of its growth,
272; fertilization, 273.
Celery, character of its growth, 275;
fertilization, 275.
Cereals, character of their growth, 177;
fertility content of, 17; fertilization,
191 et seq.; as forage crops, 241.
Chemical elements, needed in plant
growth, 2; but insufficient by them-
selves, 4.
Cherries, fertilization, 299.
Chicken manure, its composition and
value, 104.
Chili saltpetre. See nitrate of soda.
Citrous fruits, fertilization, 299.
Clay soils, their physical imperfec-
tions, 171; usually need phosphhorie
acid and lime, 170.
Climate, its infiuence on soil fertility, 4.
Clovers, character of their growth,
178; fertilization, 203; as forage crop,
249; as green manure, 120; require
liberal supply of mineral elements,
250.
Coal ashes, 111.
Commercial valuation of fertilizers,
based on commercial value of con-
INDEX
stituents, 155; schedule of values
used in, 157; objections to, 159;
advantages of, 161.
Commercial value of fertilizers, deter-
mined by trade conditions, 153; no
measure of agricultural value, 155,
158; calculation of, 162.
Corn, character of its growth, 177, 199;
fertility content of, 199; fertilization.
200; fertilization for continuous
growing, 208.
Corn forage, 242; fertilization, 243.
Corn silage, fertilization of corn for,
244,
Corn, sweet, character of its growth,
276; fertilization, 276.
Cotton, character of its growth, 305;
its fertility content, 307; fertiliza-
tion, 307-11; Georgia and South Car-
olina experiments, 309.
Cotton-hull ashes, 112.
Cotton-seed meal, its composition, 46;
used also as a cattle feed, 46; its
nitrogen availability, 55; its phos-
phorie acid availability, 65.
Cow pea, character of its growth, 251;
fertilization, 252; as forage crop,
251; as green manure, 120.
Crab, king, its composition, 43; its
Crimson clover, 120. [value, 107. _
Cucumbers, character of their growth,
273; fertilization, 274, 327.
Currants, fertilization, 303.
*
Denitrification, loss of fertility
through, 11.
Dicaleic phosphoric acid. See reverted
phosphoric acid.
Double manure salts.
potash and magnesia,
See sulfate of
Egg-plant, character of its growth, 277;
fertilization, 277.
Experiments by the farmer himself,
their value, 193.
INDEX
Farm labor, increase in cost of, 31.
Farm manures, losses in, 19; inade-
quate for demands of crops, 33.
Farm practice, irrational, 18.
Fertility, what constitutes it, 2; poten-
tial, 2, 6; practical, 6; dependent
upon usable potential fertility, 6;
influenced by moisture, climate, sea-
son, physical character of soil, 4, and
eulture, 10; loss of, by leaching 8,
by drainage 10, 12, by denitrification
11, by mechanical means 13, by
removal of crops 14; how to reduce
its loss, 9.
Fertility elements, prices received for
them in different crops, 15; contained
in milk 16, wheat 16, cereals and
vegetables 17; their usefulness not
dependent upon their source, 27.
Fertilizers, losses in, 19; their func-
tion, 21; essential manurial elements
of, 21; their indirect effect, 21, 23;
their direct effect, 23; effect of vege-
table matter in, 22; distinction
- between manures and, 22; their
value depends upon availability of
essential constituents, 24; classifi-
eation of, 124; chemical, 126; com-
mercial, 124; high-grade vs. low-
grade, 128, 146; .cf. artificial ferti-
lizers, analysis, purchase, use, and
valuation of fertilizers.
Fertilizers, complete,138; advantages of
purchasing, 140; disadvantages, 140.
Fertilizers, incomplete, 138; advantages
of purchasing, 139; disadvantages, 139.
Fertilizers, mixed, 138; their uniform-
ity, 164; conditions influencing their
use and value, 165 e¢ seq.
Fertilizer formulas, for cotton, 310;
fruit crops, 288; potatoes, 216, 220,
221; sweet potatoes, 224; tomatoes,
233, 234.
Fertilizing materials, standard or
high-grade, 125; low-grade, 124, 127;
variable in composition, 126.
ddl
Fertilizing systems, based upon spe-
cific influence of a single element,
182; based upon necessity of abun-
dant supply of the minerals,184; based
upon needs of plants as shown by
chemical analysis, 186; where ferti-
lizer is applied to money crop of
rotation, 188; an irrational system,
the “hit or miss,” 189; in a grain and
grass rotation, 198 et seq.; fertility
gained by its use, 204; system should
be modified if no farm manures are
used, 206.
Fish, dried, its source, 42; its eomposi-
tion, 42; its nitrogen availability, 55;
its phosphorie acid availability, 65.
Fish serap, crude, its composition and
Florida phosphate, 68. (value, 102,
Flowers, fertilization of, 324.
Fodder beets, fertilization, 258.
Forage crops, cereals and grasses, 241;
clovers and other legumes, 249; roots
and tubers, 257; conditions of growth,
241; as soiling crops, 254; New Jer-
sey experiments, 249.
Fruit crops, character of their growth,
181; require fertilization, 282; differ
from other farm crops, 283; fune-
tions of fertilizing elements with,
284; influence of character of soil,
285; fertilization, 287; a basic for-
mula for, 288.
Fruits, small, character of their
growth, 300; fertilization, 301 e¢ seq.
Garbage tankage, 44.
Gooseberries, fertilization, 303.
Grapes, fertilization, 303.
Grasses, character of their growth,
178; fertilization, 203 et seqg.; contin-
uous growing of, 210; as forage crops,
241; for lawns, 325.
Greenhouse crops, fertilization, 327.
Green manures, meaning of, 118; legu-
minous crops the most valuable for,
118; conditions influencing their use,
332
Green manures, continued—
119; crops available as, 120; their
value dependent chiefly upon their
nitrogen-gathering capacity, 118 et
seq.; prevent losses in fertility, 122.
See alse forage crops.
Guano, artificial, inferior to the nat-
ural product, 48; bat, 48; Ichaboe,
48; Peruvian, 47; phosphatic, its
availability, 70, 77.
Guarantee, its necessity, 129; required
by law in most states, 130; sometimes
misleading, 133; its interpretation,
134 et seq.
Gypsum, its composition,
value, 116.
115; its
Hair waste, 45, 104.
Herbaceous crops, fertilization, 324.
Home mixtures, their advantages, 141;
care required in their preparation,
141; formulas, high-grade and low-
grade, 142 et seq.; make-weight to be
avoided, 146.
Hoof meal, its composition, 42; its
nitrogen availability, 55.
Horn meal, its composition, 45; its
nitrogen availability, 55.
Ichaboe guano. See guano.
Tron phosphate, 70.
Irrational farm practice, 18, 189.
Kainit, its composition, 94; its use, 95;
preferable to muriate of potash on
sweet potatoes, 225.
King erab, 43, 107,
Lawn grasses, fertilization, 325.
Leather meal, 45; its nitrogen availa-
bility, 55.
Leguminous crops, most valuable as
green-manure, 118; lime needed by,
254. See also clovers, cow peas and
soy beans.
INDEX
Lemons, fertilization, 299.
Lettuce, character of its growth, 277;
fertilization, 277, 327.
Liebig’s organic chemistry, ete., 28.
Lime, its source, 113; its composition,
114; quick-lime, 114; marble, 114;
oyster shell, 114: gas, 115; care needed
in its use, 115; its value, 114 et seq.;
needed by legumes, 254; its action on
fruit-crops, 285.
Lime-kiln ashes, 110.
Linseed meal, its composition, 46;
used also as a cattle-feed, 46.
Lobster shells, 108.
Lucerne. See alfalfa.
Maize. See corn.
Make-weight in fertilizers, cost of
handling, 146.
Manures. See fertilizers and green-
manures.
Market-garden erops, character of
their growth, 180, 262; fertilization,
264; a basic fertilizer for, 267.
Marl, its composition, 112; soil im-
proved by its use, 113.
Meadows, fertilization, 211.
Meat, dried. See ammonite.
Milk, fertility content of, 16.
Millet, fertilization, 249; fertility con-
tent of, 249.
Moisture. See water.
Monoealcie phosphorie acid. See solu-
ble phosphorie acid.
Muck, its composition, 106; used as a
source of humus, 106; how secured,
107.
Muriate of potash, its composition,
96; its bad effects on tobacco and
sugar-beets, 94; how to convert into
actual potash, 134.
Muskmelons, character of their growth,
273; fertilization, 274.
Mussels, their composition and value,
107.
Mustard, as a green-manure, 122.
INDEX
Nitrate of soda, its source, 52; its com-
position and value, 52; its availa-
bility, 53; compared with sulfate
of ammonia, 53; how to convert
into nitrogen, 134; valuable as fer-
tilizer for tomatoes, 227.
Nitrogen, its action on fruit crops, 284;
its availability 53 et seq., how esti-
mated 54, modified by crop 55, season
55, and object of use 56; of the air
available to leguminoss, 38; how to
convert into ammonia, 134; exists in
the air, 38; its different forms, 25, 39
et seq.; its illusiveness, 8; important
because easily lost and expensive, 8;
conditions determining its loss, 9;
loss by drainage 10, by escape as
gas 11, by leaching 9; necessary for
plant growth, 3; nitrate the most
valuable form, 52; organic, 39 et seq.;
its availability, 54; its sources, 38;
its unstability, 8; how it is used by
the plant, 50, 52.
Oats, character of its growth, 177;
fertilization, 201; continuous grow-
ing of, 209; pouting period in its
growth, 247.
Oats and peas, fertilization, 248.
Oats forage, fertilization, 247.
Onions, character of their growth, 278;
fertilization, 280.
Onion sets. See onions.
Oranges, fertilization, 299.
Organic nitrogen, what it is, 39; its
forms, 40 et seq.; its availability, 54.
Peaches, need and advantages of fer-
tilization, 294; methods of, 297; New
Jersey experiments, 294.
Peanuts, fertilization, 324.
Pears, fertilization, 291-3.
Peas, fertilization, 270; see also barley
and oats.
Peat. See muck.
Peruvian guano. See guano.
333
Phosphate of lime in bones, 60.
Phosphates, correct and false use of
the term, 58; animal, 59 et seq.;
mineral, 66 et seg.; South Carolina
rock, 67; Florida, 68; Canadian apa-
tite, 69; Tennessee, 69; iron 70, its
availability 76; how used by plants,
71; insoluble in water, 72; useful-
ness depends upon rate of decay,
72; availability depends upon their
source 72, fineness of division 73,
character of soil 74, and kind of crop
74; different from superphosphates,
83. See also bone meal.
Phosphate slag, 70.
Phosphoric acid, necessary for plant
growth, 3; its loss through drainage,
12; its different forms, 25; insoluble,
78; soluble, 79; chemically identical
independent of its source, 82; re-
verted 80, theory of its formation 85,
its value 86; tetra-calcic, 80; mean-
ing of available, 88; remains in soil
until removed by plants, 90; its fixa-
tion in the soil, 91; how to convert
into bone-phosphate, 134; its action
on fruit crops, 285.
Pigeon manure, 49, 105; its inferiority
to natural guanos, 49.
Plant-food, available, 24; unavailable,
34; necessity of adding more than is
required by definite increase of crop,
205; loss from use of soluble, 26;
ef. fertilizers.
Plants, vary in power of acquiring
food, 177.
Plot experiments, scheme for, 194;
their interpretation, 196; their value,
196; results of, 197.
Plums, fertilization, 299.
Potash, necessary for plant growth, 3;
its loss through drainage, 12; its dif-
ferent forms, 25, 93; its importance,
92; importance of form, 93; its fixa-
tion in the soil, 98; how to convert
actual into muriate and sulfate, 134;
304
Potash, continued—
its action on fruit crops, 284; see
also kainit, sylvinit, muriate and
sulfate of potash.
Potash salts, their occurrence, 92; their
uniformity of price, 92.
Potatoes, fertility content of, 215; fer-
tilization for early, 215 et seq.; fer-
tilization for late, 220; sulfate of
potash improves their quality, 219;
importance of form of fertilizing
elements, 219; New York (Geneva)
experiments, 215, 218.
Poultry manure, 49, 104; its composi-
tion, 104.
Powder waste, 117.
Pumpkins, character of their growth,
273; fertilization, 274.
Purchase of fertilizers, the unit basis
128, its advantages 129; the ton basis,
129, its defects, 129; law not sufficient
for protection, 130; intelligence
needed, 131; codperative, 148; meth-
ods of 138, by buying raw materials
138, by buying mixed brands 188,
advantages and disadvantages of
each method, 138.
Rape, fertilization, 260.
Raspberries, fertilization, 302.
Rhubarb, character of its growth, 277;
fertilization, 278.
Root erops, character of their growth,
179; fertility content of, 258; ferti
lization, 258.
Roses, fertilization, 324.
Rye, as green manure, 122; as substi-
tute for wheat in rotation, 207; fertili-
zation for continuous growing, 209.
Rye forage, fertilization, 245, 246.
Sandy soils, their physical imperfec-
tions, 170; usually need potash, 170.
Seallions, character of their growth,
279; fertilization, 280.
Season, its influence on soil fertility, 4.
INDEX
Sea weed, 108.
Sewage, its composition and value, 105.
Soda, nitrate of. See nitrate.
Soil fertility, its importance, 1; what
constitutes, 1; influenced by moist-
ure, climate and season, 4; qualified
by location of soil, 5.
Soiling crops, scheme for, 255; New
Jersey experiments, 256.
Soils, influence of physical character
of, 4; their derivation a guide as to
deficiencies, 168. See clay and sandy
soils.
Sorghum, fertilization, when grown for
forage and for sugar, 322.
South Carolina rock. See phosphate
and superphosphate.
Soy bean, as forage crop, 120, 251;
character of its growth, 251; fer-
tilization, 251.
Spinach, character of its growth, 277;
fertilization, 277.
Sprouts. See Brussels sprouts.
Squashes, character of their growth,
273; fertilization, 274.
Strawberries, fertilization, 30d.
Sugar-beets, fertility content of, 236;
fertilization when grown for sugar
237, when grown for fodder, 258;
effect of previous deep cultivation
on, 239.
Sugar-cane, fertility content of, 318;
fertilization, 318; Louisiana experi-
ments, 317.
Sulfate of ammonia, its composition,
51; its source, 51; advantages of its
use, 51; its availability, 53; com-
pared with nitrate of soda, 53; how
to convert into nitrogen, 134.
Sulfate of lime. See gypsum.
Sulfate of potash, its composition, 97;
preferable to muriate for some crops,
94, 219; how to convert into actual
potash, 134.
Sulfate of potash and magnesia, its
composition, 97.
(ag
a
INDEX
Superphosphates, how made, 80; dif-
ferences due to source, 81, 83; differ-
ent from phosphates, 83; bone, 83,
88; mineral, 84, 88; double, 87, 89;
their composition, 88; bone-black,
88; South Carolina rock, 88; Florida,
89; Tennessee, 89; should contain no
free acid, 89.
Swedes, fertilization, 260.
Sweet potatoes, quality an important
factor in, 221; fertility content of,
222; fertilization, 222 et seq.; Georgia
experiments, 223; New Jersey experi-
ments, 223, 226.
Sylvinit, its composition, 95; its use,
96.
Tan-bark ashes, their composition, 110.
Tankage, its source, 43; its composi-
tion, 44; concentrated, 43; its varia-
bility, 44; its nitrogen availability, 55;
see also bone and garbage tankage.
Tennessee phosphate. See phosphate.
Tetra-calecic phosphoric acid. See
phosphorie acid.
Thomas phosphate meal.
phosphate.
Timothy, character of its growth, 178;
fertilization, 203.
Tobacco, fertility content of, 312;
effect of fertilizers on quality, 312;
injurious effect of chlorids, 315; fer-
tilization, 313 et seq.; Connecticut
experiments, 313.
See iron
Tobacco stems, their composition, 100; ©
their value, 101.
Tomatoes, fertilization for early, 227,
for late, 231; composition of vine,
233; composition of fruit, 233;
300
nitrate of soda as fertilizer for, 227,
235; New Jersey experiments, 226.
Tri-calecic phosphoric acid. See insolu-
ble phosphorie acid.
Tuber crops, for forage, 261.
Turnips, fertilization, 260, 271; char-
acter of their growth, 270.
Unit system of purchase, 128.
Use of fertilizers, object of, 167;
conditions modifying, 167 et seq.;
knowledge of nature of soil neces-
sary in, 170; influence of previous
treatment and cropping on, 172;
influence of character of crop, 175;
influence of method of farming, 176;
importance of system in, 198.
Valuation of fertilizers. See commer-
cial valuation.
Vegetable matter in manures, its effect
on physical character and absorptive
power of soils, 22.
Vegetables, fertility content of, 17.
Ville’s system of fertilization, 182.
Waste from phosphorus works, 116.
Water, its influence on soil fertility, 4.
Watermelons, character of their
growth, 273; fertilization, 274.
Wheat, fertility content of, 16, 192;
character of its growth, 177; fer-
tilization 202, for continuous grow-
ing of, 208.
Wheat forage, fertilization, 245.
Wood ashes, their composition, 109;
valuable source of potash, 110.
Wood waste, 45; its composition, 103;
its nitrogen availability, 55.
The Best and Newest
Rural Books
WO series of books on leading topics con-
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Tht RURAL SCIENCE SERIES
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THE FERTILITY OF THE LAND. By I. P. Roperts, of Cornell Univer-
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THE SPRAYING OF PLANTS. By E. G. LopEMAN, late of Cornell Uni-
versity. 399 pp. $1.
MILK AND ITS PRODUCTS. By H. H. Wing, of Cornell University.
280 pp. $1.
THE PRINCIPLES OF FRUIT-GROWING. By L. H. Barney. 520 pp. $1.25.
BUSH FRUITS. By F. W, Carp, of Rhode Island College of Agriculture
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PHYSIOLOGY OF PLANTS. By J. C. ArtHur, Purdue University.
PRINCIPLES OF BREEDING OF ANIMALS. By W. H. BREweER, of
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PLANT PATHOLOGY. By B. T. GALLoway and associates of U.S. Depart-
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SEEDS AND SEED-GROWING. By G. H. Hicks, of U.S. Dept. of Agr.
LEGUMINOUS PLANTS AND NITROGEN-GATHERING. By E. W.
HILGARD, of University of California.
FEEDING OF ANIMALS. By W.H. Jorpan, of New York State Experi-
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IRRIGATION AND DRAINAGE. By F. H. Kina, University of Wisconsin.
FERTILIZERS. By E. B. VooruEEs, of New Jersey Experiment Station.
RURAL WEALTH AND WELFARE. By GrorGE T. FAIRCHILD, Ex-Presi-
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-FARM POULTRY. By GreorGe ©. WATSON, of Pennsylvania State College.
THE RURAL SCIENCE SERIES
HE SOIL. Its Nature, Relations and
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functions, origin and wasting of soils; texture, composition and
kinds of soils; nitrogen of the soil; capillarity, solution, diffusion,
and osmosis; soil water; conservation of soil moisture; distribu-
tion of roots in the soil; soil temperature; relations of air to the
soil; farm drainage; irrigation; physical effects of tillage and
fertilizers.
“T consider it a most desirable addition to our agricultural literature,
and a distinct advance over previous treatises on the same subject, not
only for popular use, but also for students and specialists, who will find
many new and useful suggestions therein.”
E. W. HILGARD,
Director of Agricultural Experiment Station,
Berkeley, Cal.
“It is a book which progressive farmers will come to regard as one
of the essential implements of farm life.”—Boston Daily Advertiser.
“The manual is brief, accurate, comprehensive, and hits the practical
point every time.”—Independent.
THE RURAL SCIENCE SERIES
Pe FERTILITY OF THE-LAND: A
Summary Sketch of the Relationship of
Farm-Practice to the Maintaining and In-
creasing of the Productivity of the Soil.
By I. P ROBERTS, Director of the College of Agri-
culture, Cornell University.
SECOND EDITION—432 PACES—45 ILLUSTRATIONS—$1.25
This work, written by one who has been termed
“the wisest farmer in America,” takes up the treat-
ment of the soil from the standpoint of the farmer
rather than that of the scientist. It embodies the
results of years of careful experimentation and obser-
vation along practical lines, and will be found help-
ful and inspiring to a marked degree. No other one
-book could be so heartily recommended to the pro-
gressive farmer, on subjects of vital interest to him,
as this fresh and interesting series of talks—for Pro-
fessor Roberts seems to be personally addressing the
reader.
THE FERTILITY OF THE LAND includes A Chat with the Young
Farmer ; Inventory of the Land ; Evolution of the Plow (fully illus-
trated); The Means and Philosophy of Tilling the Land (telling how
and why we should plow, harrow, etc.); Conserving Moisture ; Irri-
gation and Drainage; Manures (in four unique, illustrated chap-
ters); Nitrogen; Potash and Phosphoric Acid; Lime and other
dressings ; Commercial Fertilizers ; The Use of Clovers, Fallows
and Rotations ; Appendix.
“In short, the book will be found helpful to the farmer, in that it will
enable him to go through the routine of his everyday work with intelli-
gence, and, therefore, with skill and the assurance of wider success.”—
Garden and Forest.
THE RURAL SCIENCE SERIES
HE SPRAYING OF. PLANTS: 3%
Succinct Account of the History, Principles
and Practice of the Application of Liquids
and Powders to Plants for the Purpose of
Destroying Insects and Fungi. By E. G.
LODEMAN, late Instructor in Horticulture in the
Cornell University.
399 PACES—9$2 ILLUSTRATIONS—$1.00
In these days this subject is conceded to be of
especial importance to the horticulturist; for it is
only by intelligent spraying that many large fruit
interests are saved from utter extinction. Professor
Lodeman treats the subject both historically and
practically, and the work forms the only complete
manual of spraying, being admittedly the standard
authority. Not only is spraying discussed in its
relations to the plant or tree and the crop, but the
diseases and insects which are to be combatted are
most fully presented.
THE SPRAYING OF PLANTS includes in its first part a complete
history of the rise of spraying, both in this country and abroad.
There are also full illustrated accounts of pumps and nozzles, com-
plete recipes of formulas, and the like. The second part, compris-
ing 135 pages, entitled “Specific Directions for Spraying Cultivated
Plants,” is an alphabetical illustrated account of the various insects
and fungi, with methods of treating them.
“Mr. Lodeman has gathered the results of an immense amount of
experiments, both in Europe and America, and his book ean be trusted not
only as a manual of practice, but as a true and well classified record of our
knowledge on this subject at the present time.”—Garden and Forest.
“There is nothing else “ the subject so new, complete, accurate and
available.”—Evening Post (N.Y.).
THE RURAL SCIENCE SERIES
fe AND ITS “PRODUCTS: (A
Treatise upon the Nature and Qualities of
Dairy Milk, and the Manufacture of But-
ter and Cheese. By HENRY H. WING, Assis-
tant» Professor of Dairy Husbandry in the Cornell
University.
208 PAGES—33 ILLUSTRATIONS—$1.00
In this volume the whole field of dairying is in-
telligently considered. The production and charac-
ter of the lacteal fiuid are first discussed, and then
in order are taken up the marketing of milk, the
production and handling of butter, cheese, and all
the products of the dairy. Although the book is
up to date in its science, it is none the less a com-
plete guide to modern dairy practice. The illustra-
tions serve to point the practical recommendations
of the text. No recent work on dairying has been
so well received as this.
MILK AND Its PrRopucts includes chapters on: Secretion of
Milk ; Composition of Milk; Testing of Milk; Ferments and Fer-
mentations of Milk, and their Control ; Market Milk ; Separation of
Cream ; Ripening of Cream; Churning; Finishing and Marketing
Butter; Milk for Cheese-Making; Cheddar Cheese-Making; Varie-
ties of Cheese; By-Products of the Dairy; Butter and Cheese Fac-
tories; Statistics and Economics of the Dairy Industry; Appendix,
comprising useful rules and tests, metric system, dairy laws, and
references to dairy literature.
“The book is a mine of valuable information, and ought to be in the
hands of all progressive dairymen.”—New England Farmer.
THE RURAL SCIENCE SERIES
HE PRINCIPLES OF FRO
GROWING. By L. H. BAILEY, Professor of
Horticulture in the Cornell University.
520 PACGES—114 ILLUSTRATIONS—$1.25
There have been manuals and treatises on fruit-
growing, but this volume is the first consistent
presentation of the underlying principles affecting
the growth of the various fruits. It is thus unique,
and it occupies: a field of the greatest importance.
It joins science and practice, for it not only discusses
the reasons for certain operations, but presents the
most approved methods, gathered from the successful
fruit-growers of America. It appeals especially to
the horticulturist who is willing to have his brain
direct and supplement the work of his hands, and to
acquire a knowledge of principles rather than a mere
memorandum of their application.
THE PRINCIPLES OF FRUIT-GROWING includes: Introductory
Discussion, comprising an inventory and elassification of fruits, the
fruit zones, the outlook for fruit-growing; the Location and its
Climate, with a full discussion of frosts; the Tilling of Fruit
Lands; the Fertilizing of Fruit Lands; the Planting of Orchards;
Secondary Care of Orchards; Diseases, Insects and Spraying;
Picking and Packing aud Storing Fruits, Shipping, etc.; and a
bibliography of American writings on the subject.
“The book is very practical in its treatment of the subject of fruit-
growing, after a brief introductory entering at once into the discussion of
the location of the orchard, following that with the tillage of fruit lands,
dealing with the planting and eare of fruits. Taken all in all, it is the most
pe book on fruit-growing at a small price we have seen.”— Western
rural.
THE RURAL SCIENCE SERIES
USH-FRUITS: A Horticultural Mono-
graph of Raspberries, Blackberries, Dew-
berries, Currants, Gooseberries, and other
Shrub-like Fruits. By FRED W. CARD, Pro-
fessor of Horticulture in the Rhode Island College of
Agriculture and Mechanic Arts, and Horticulturist to
the Experiment Station.
549 PACES—113 ILLUSTRATIONS—$1.50
The great importance in this country of the fruits
mentioned in the title justifies their treatment in a sep-
arate monograph. Professor Card, with a lifelong
training as a grower of these fruits, as well as years
of study as experimenter and teacher, takes up the
subject with special fitness. Not only are the fruits
treated with respect to culture, varieties, history, etc.,
but the diseases and the insects which attack them
- are fully discussed. There are numerous illustrations,
and the volume is an important contribution to the
literature of fruit-growing.
BusH-FrRuits includes in Part J An Introductory Discussion
(Loeation, Fertilizers, Planting and Management, Pruning, Winter-
killing, Propagation, Thinning, Effect of Spraying on Pollination,
Forcing, Picking, Packages and Marketing).
Part II treats of the Brambles; Red Raspberries (Soil, Location,
Fertilizing, Propagation, etc., Autumn Fruiting, Marketing, Duration,
Hardiness, Yields, Normal Profits); Black Raspberries (Soil, ete.,
Harvesting, Drying. Marketing, the Evaporated Raspberry Industry,
Usual Profits); Blackberries (Soil, ete., Marketing, etc.): Dewberries
(Soil, ete., Marketing, etc.); Miscellaneous Brambles (Mayberry,
Strawberry-Raspberry, Wineberry, Chinese Raspberry, Ornamental
Species); Varieties of Raspberries; Varieties of Blackberries and
Dewberries; Yields; Insects; Diseases; Botany.
Part III discusses the Groselles; Currants (Soil, Fertilizers, Propa-
gation, Planting, Tillage, Pruning, Gathering and Marketing, Uses,
Duration, Hardiness, Yield, Profits); Gooseberries (Soil, ete., Hardi-
ness, Profits); Varieties of Currants; Varieties of Gooseberries;
Injurious Insects; Diseases; Botany. ;
Part IV treats Miscellaneous Types, including other Species of
Bush-Fruits (Buffalo Berry, The Goumi, Huckleberries, Juneber-
ries, Tree Cranberry, Barberry, Sand Cherry); Appendix.
THE GARDEN-CRAFT SERIES
THE GARDEN-CRAFT SERIES
Comprises practical hand-books for the horticultur-
ist, explaining and illustrating in detail the various
important methods which experience has demon-
strated to be the most satisfactory. They may be
called manuals of practice, and though all are pre-
pared by Professor BatLEy, of Cornell University,
they include the opinions and methods of success-
ful specialists in many lines, thus combining the
results of the observations and experiences of nu-
merous students in this and other lands. They are
written in the clear, strong, concise English and in
the entertaining style which characterize the author.
The volumes are compact, uniform in style, clearly
printed, and illustrated as the subject demands.
They are of convenient shape for the pocket, and
are substantially bound in flexible green cloth.
THE HORTICULTURIST’S RULE BOOK. By L.H. Battery. Fourth edi-
tion. 312 pp. 75 cts.
THE NURSERY-BOOK. By L. H.Baixtey. Third edition. 365 pp. $1.
PLANT-BREEDING. By L. H. BaiLey. 293 pp. $1. “¥
THE FORCING-BOOK. By L.H.Bainey. 280 pp. $1.
GARDEN-MAKING. By L.H. Barney. Second edition. 425 pp. $1.
THE PRUNING-BOOK. By L. H. Barney. 540 pp. $1.50.
OTHER WORKS BY PROFESSOR
BAILEY.
THE SURVIVAL OF THE UNLIKE. Second edition. 515 pp. $2.
LESSONS WITH PLANTS. 523 pp. $1.10 net.
FIRST LESSONS WITH PLANTS. 127 pp. 40 cts. net.
THE GARDEN-CRAFT SERIES
ee HORFICULTURIST’S. RULE-
BOOK: A Compendium of Useful Infor-
mation for Fruit-growers, Truck-gardeners,
Florists, and others. By L. H. BAILEY, Pro-
fessor of Horticulture in the Cornell University.
FOURTH EDITION—812 PACES—75 CENTS
A vast mass of information is presented in this
handy little reference book, arranged so carefully
and indexed so completely that instant reference may
be made to any one of the two thousand entries.
The things you want to know about horticultural
work, the remedy for a plant disease, the way to
conquer a troublesome insect enemy—all are con-
cisely set forth. It is a collection of verified and
digested facts, in compact form, easy of reference
and comprehensive in range. Now in its fourth
edition, the book has become a standard reference
work.
THE HorrTIcULTURIST’S RULE-Book presents information upon
such matters as recipes for insecticides and fungicides, descriptions
(with remedies) of insects and diseases, weeds, lawns, grafting-
waxes, seed and planting tables, tables of yields, rules for green-
house heating and management, with figures, methods of storing
produce, tariff and postal rates, rules of societies for naming and
exhibiting specimens, score-cards and scales of points, analyses of
fertilizing substances, lists of current horticultural books and
journals.
“Tt is packed from cover to cover with a vast amount of useful infor-
mation for every one who grows fruit, flowers, or plants of any kind. All
kinds of useful tables are given, which are very convenient to any one,
whether a horticulturist or not.”—California Fruit-Grower.
THE GARDEN-CRAFT SERIES
HE NURSERY BOOK: A Complete
Guide to the Multiplication of Plants. By
L. H. BAILEY, Professor of Horticulture in the Cor-
nell University.
THIRD EDITION—365 PACES—152 ILLUSTRATIONS—$1.00
The detailed questions of propagation are an-
swered in this admirable volume, which has become
the standard work of reference for nurserymen. It
is now in its third edition, and has been thoroughly
revised and greatly extended. It is intensely prac-
tical, and fully sets forth the processes of budding,
grafting, seed-sowing, etc., as well as many other
important items of nursery work. It is simply
essential to the seedsman, nurseryman, florist or
grower of plants in any walk of life. As with all
Professor Bailey’s works, there are unusually com-
plete indexes and glossaries, rendering the book moet
convenient in use.
THE NuRSERY-Book includes Seedage (Requisites of Germina-
tion, Seed-Testing, Handling and Sowing of Seeds); Separation and
Division; Layerage; Cuttage (General Requirements of Cuttings,
Various Kinds of Cuttings); Graftage (General Considerations, Bud-
ding, Grafting, Inarching, Grafting Waxes); Nursery Management
(Nursery Lands, Grades of Trees, Storing and Trimming Trees,
ete.); The Nursery List (an alphabetical catalogue of about 1,500
plants, with directions for their multiplication).
“This book should be in the home of not only every horticulturist, but
of every family irrespective of occupation who love flowers or ornamental
plants, for it treats of the propagation of these as well as ‘food plants.’ It
contains chapters on Seedage, Separation and Division, Layerage, Cuttage,
Graftage, and the Nursery List. Besides, it contains a glossary of great
ane to the aspiring horticulturist.”—Michigan Fruit-Grower and Practical
armer.
THE GARDEN-CRAFT SERIES
LANT-BREEDING: Being Five Lectures
upon the Amelioration of Domestic Plants.
By L. H. BAILEY, Professor of Horticulture in the
Cornell University.
293 PAGES — 20 ILLUSTRATIONS — $1.00
A work of unique interest, it being the only
volume upon this subject. When one considers the
marvelous changes in our fruits, vegetables and
flowers within a generation through the work of
man, in turning to his purposes the impulses of
nature, the great interest of this book may be indi-
eated. It tells how varieties of cultivated plants
come about, and further, how one may engage in
the fascinating work of originating them. The
grower who gropes in the dark in his search for
the ideal fruit or flower may here find guidance and
aid in the principles governing .the work.
PLANT-BREEDING comprises five chapters: The Fact and
Philosophy of Variation; The Philosophy of the Crossing of Plants;
How Domestic Varieties Originate; Borrowed Opinions, being trans-
lations from the writings of Verlot, Carriére and Focke; Pollination,
or How to Cross Plants. Chapter III. contains the list of fifteen
rules for plant-breeding which De Varigny, the eminent French
writer, has called “the quindecalogue of the horticulturist.”
“ Professor Bailey’s elucidation of the matter will be found clear, simple,
direct, as far as possible untechnical, and so written as to make a pleasant
appeal to every intelligent reader, even though not deeply versed or very
specially interested in botanical science.”—Country Gentleman.
“The author has here collected and brought together a good deal of in-
formation about the origination of new forms of plants not otherwise easily
obtainable, and thereby renders no small service to horticulturists in search
of such knowledge.”—American Agriculturist.
THE GARDEN-CRAFT SERIES
HE FORCING-BOOK: A Manual of
the Cultivation of Vegetables in Glass
Houses. By L. H. BAILEY, Professor of Horti-
culture in the Cornell University.
280 PACES—88 ILLUSTRATIONS—$1.00
No subject in horticulture has more rapidly
assumed importance than that of bringing into use
out of season various vegetables and fruits. If one
stops to think of the deprivation there would be,
even of the danger to health, in the cessation of this
“foreing,” and further, if an idea is gained of the
extensive business done in out-of-season products,
the importance of this complete littie manual will
be understood. It describes forcing-houses best
adapted; tells what crops may be grown and
marketed, and how best to do the work. It is a
convenient record of long experience and careful
experimentation.
THE Forcine-Booxk includes Introductory Suggestions (Cate-
gory of Forcing Crops, Locations for Vegetable Forcing, Cost of
Heat and Labor); Construction of the Forcing-House (Types and
Forms of Houses, Structural Details, Heating, Cost); Management
of the Forcing-House (Temperature, Soils, Fertilizers, Watering,
Ventilating and Shading, Electric Light, Pollination, Insects and
Diseases); Lettuce; Cauliflower; Radish; Asparagus and Rhubarb;
Miscellaneous Cool Plants (Celery, Salads, Onion, Beet, Potato,
Pepino); Tomato; Cucumber; Muskmelon; Miscellaneous Warm
Plants (Bean, Eggplant, Pepper, Cyphomandra); Summaries of the
Management of the Various Crops.
“No vegetable forcer should be without it in his library. * * * There
has been wanting a handy reference book for the growing of vegetables under
glass. * * * Professor Bailey’s contribution will leap into first place,
and we think will stay.”—American Gardening.
THE GARDEN-CRAFT SERIES
ARDEN-MAKING: Suggestions for the
Utilizing of Home Grounds. By L. H.
BAILEY, aided by L. R. TAFT, W. A. WAUGH,
and ERNEST WALKER.
417 PAGES —256 ILLUSTRATIONS — $1.00
Here is a book literally “for the million” who in
broad America have some love for growing things,
and in the general ownership of the soil find the
opportunity for its indulgence. “Every family ean
have a garden. If there is not a foot of land, there
are porches or windows. Wherever there is sun-
light, plants may be made to grow; and one plant
in a tin-can may be a more helpful and inspiring
garden to some mind than a whole acre of lawn and
fiowers may be to another.” Thus Professor Bailey
introduces his subject, and the book which follows
is one to instruct, inspire, edify and educate the
reader, if he can raise his eyes from city cobble-
stones! It tells of ornamental gardening of any
range, with lists of trees and shrubs most suitable
for various effects; treats of fruits and of vege-
tables for home use, and gives the word of instruc-
tion so often wanted, but hitherto unattainable in
any one simple and compact book. No modern
American work covers this important field. The
illustrations are numerous and beautiful.
GARDEN-MAKING includes General Advice; The Plan of the
Place; the Picture in the Landscape, How to Make the Improve-
ments, etc.; Planting the Ornamental Grounds; The Fruit Planta-
tion; The Vegetable Garden; Seasonal Reminders (Calendars for
the North and for the South).
THE GARDEN-CRAFT SERIES
HE PRUNING-BOOK: A Monograph
of the Pruning and Training of Plants as
Applied to American Conditions. By L. H.
BAILEY, Professor of Horticulture in the Cornell
University.
540 PACES—332 ILLUSTRATIONS—$1.50
Until the appearance of this book, there had been
no complete and consistent discussion of pruning.
Professor Bailey considers fully the philosophy of
the subject, showing why we should prune, with
such statements of experience’ and observation as
will enlighten the reader. In his admirable treat-
ment of the science he first states principles; and
then the various practices of pruning are considered
in full detail, and a vast fund of carefully collected
data, embodying the experiences of many students
in our own and other lands, is made serviceable to
the reader. The illustrations are numerous and re-
markably convineing.
THE PRUNING-BooK includes The Philosophy of Pruning (Does
Pruning Devitalize Plants?); The Fruit-Bud (The Bud and the
Branch, The Leaf-bud and the Fruit-bud, The Fruit-spur, The
Peach and the Apricot, Co-terminal Fruit-bearing, Grapes and
Brambles, How to Tell the Fruit-buds, Summary Synopsis); The
Healing of Wounds (Nature of Wounds, Suggestions to the Pruner,
When to Cut, Dressings for Wounds, How to Make the Cut,
Mending Trees); The Principles of Pruning (Top-pruning, Root-
pruning, Variation of Habit, Watersprouts, Heading-in, Obstruc-
tions, Checking Growth, Fruit-bearing, Girdling, ete., General
Law); Some Specific Advice (Form of Top, Root-pruning, Subse-
quent Treatment, Ringing and Girdling, Pruning Tools, Remarks
on Specific Plants); Some Specific Modes of Training, American
Grape Training, Vinifera Grape Training.
WORKS BY PROFESSOR BAILEY
KETCH OF THE EVOLUTION OF
OUR NATIVE FRUITS. sy Lv. H.
BAILEY, Professor of Horticulture in the Cornell
University.
485 PACES—125 ILLUSTRATIONS —$1.50
In this entertaining volume, the origin and de-
velopment of the fruits peculiar to North America
are inquired into, and the personality of those horti-
cultural pioneers whose almost forgotten labors
have given us our most valuable fruits is touched
upon. There has been careful research into the
history of the various fruits, including inspection
of the records of the great European botanists who
have given attention to American economic botany.
The conelusions reached, the information presented,
and the suggestions as to future developments, can-
not but be valuable to any thoughtful fruit-grower,
while the terse style of the author is at its best in
his treatment of the subject.
THE EVOLUTION OF OUR NATIVE FRUITS discusses The Rise of
the American Grape (North America a Natural Vineland, Attempts
to Cultivate the European Grape, The Experiments of the Dufours,
The Branch of Promise, John Adlum and the Catawba, Rise of
Commercial Viticulture, Why Did the Early Vine Experiments Fail ?
Synopsis of the American Grapes); The Strange History of the Mul-
berries (The Early Silk Industry, The “* Multicaulis Craze,”); Evolu-
tion of American Plums and Cherries (Native Plums in General;
The Chickasaw, Hortulana, Marianna and Beach Plum Groups,
Pacific Coast Plum, Various Other Types of Plums, Native Cherries,
Dwarf Cherry Group); Native Apples (Indigenous Species, Amelio-
ration has begun); Origin of American Raspberry-growing (Early
American History, Present Types, Outlying Types); Evolution of
Blackberry and Dewberry Culture (The High-bush Blackberry and
Its Kin, The Dewberries, Botanical Names); Various Types of
Berry-like Fruits (The Gooseberry, Native Currants, Juneberry,
Buffalo Berry, Elderberry, High-bush Cranberry, Cranberry, Straw-
berry); Various Types of Tree Fruits (Persimmon, Custard-Apple
Tribe, Thorn-Apples, Nut-Fruits); General Remarks on the Improve-
ment of our Native Fruits (What Has Been Done, What Probably
Should Be Done).
WORKS BY PROFESSOR BAILEY
HE SURVIVAL OF THE UNLIKE:
A Collection of Evolution Essays Suggested
by the Study of Domestic Plants. By L. H.
BAILEY, Professor of Horticulture in the Cornell
University.
SECOND EDITION— 515 PAGES — 22 ILLUSTRATIONS — $2.00
To those interested in the underlying philosophy
of plant life, this volume, written in a most enter-
taining style, and fully illustrated, will prove wel-
come. It treats of the modification of plants under
cultivation upon the evolution theory, and its atti-
tude on this interesting subject is characterized
by the author’s well-known originality and inde-
pendence of thought. Incidentally, there is stated
much that will be valuable and suggestive to the
working horticulturist, as well as to the man or
woman impelled by a love of nature to horticul-
tural pursuits. It may well be called, indeed, a
philosophy of horticulture, in which all interested
may find inspiration and instruction.
THE SURVIVAL OF THE UNLIKE comprises thirty essays touching
upon The General Fact and Philosophy of Evolution (The Plant
Individual, Experimental Evolution, Coxey’s Army and the Russian
Thistle, Recent Progress, etc.); Expounding the Fact and Causes of
Variation (The Supposed Correlations of Quality in Fruits, Natural
History of Synonyms, Refiective Impressions, Relation of Seed-
bearing to Cultivation, Variation after Birth, Relation between
American and Eastern Asian Fruits, Horticultural Geography, Prob-
lems of Climate and Plants, American Fruits, Acclimatization, Sex
in Fruits, Novelties, Promising Varieties, etc.); ard Tracing the
Evolution of Particular Types of Plants (the Cultivated Strawberry,
Battle of the Plums, Grapes, Progress of the Carnation, Petunia,
The Garden Tomato, etc.).
THE MACMILLAN COMPANY,
66 Fifth Avenue, NEW YORK.
LIBRARY OF CONGRESS
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