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THE EFFECT OF LARGE APPLICATIONS OF COM-
MERCIAL FERTILIZERS ON CARNATIONS

BY

FRED WEAVER MUNCIE

A. B. Wabash College, 1910
M. S. University of Illinois, 1913

THESIS

Submitted in Partial Fulfilment of the Requirements
for the Degree of

DOCTOR OF PHILOSOPHY

IN CHEMISTRY

THE GRADUATE SCHOOL

OF THE

UNIVERSITY OF ILLINOIS

1915

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ACKNOWLEDGMEN TS.

members of the Be saraseats of Ghemcte and Botany:

LIBRARY OF CONGRESS

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THE EFFECT OF LARGE APPLICATIONS OF COM-
MERCIAL FERTILIZERS ON CARNATIONS

BY

FRED WEAVER MUNCIE

A. B. Wabash College, 1910
M. S. University of Illinois, 1913

THESIS

Submitted in Partial Fulfilment of the Requirements
for the Degree of

DOCTOR OF PHILOSOPHY

IN CHEMISTRY

THE GRADUATE SCHOOL

OF THE

UNIVERSITY OF ILLINOIS

1915

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Effects of Large Applications of Commercial Fer-
tilizers on Carnations

By FRED WEAVER MUNCIE

In the investigation of the use of commercial fertilizers in growing
carnations by the Illinois Agricultural Experiment Station, it has been
found that the lack of appreciation by florists of the relatively high plant
food concentrations and often high solubilities of commercial fertilizers,
as compared with manure, has often led to a complete loss of a crop of
flowers in an effort to produce an extraordinarily large one. On this
account, it was considered desirable to study the causes ‘and effects of
overfeeding with the more ordinarily used commercial fertilizers.

The fertilizers chosen for the experiment were dried blood, sodium
nitrate and ammonium sulfate, acid phosphate and disodium phosphate,
and potassium sulfate. For comparison, sodium chloride and sodium
sulfate also were used on some sections. Experimental work upon the
subject was carried out during the years 1912-15. ;

Carnations are propagated by means of cuttings, and from these it was’
found impossible to secure a normal growth in either sand or water cultures.
Hence, the experimental work was based upon the study of plants grown
in soil carefully selected with the view to securing uniformity throughout
the benches, watered to give as nearly as possible the same moisture
“content, and subjected very nearly to identical conditions of heat, ventila-
tion, and illumination. For details regarding the type of soil, its prepara-
tion, arrangement of sections, etc., the reader is referred to Bull. 176
of the Illinois Agricultural Experiment Station.

4

The method consisted of weekly applications of the fertilizers at various
rates upon isolated sections in the benches, beginning about October 1
and continuing until about May 1 or until injury became serious.

Effects of Overfeeding on Condition of Plants.—The rapidity with
which the sections of carnations became affected followed in a general
way the solubility of the fertilizer used.* The solubilities** of the pure
substances in water per hundred parts at o° are given in Table I.

TABLE I.—SOLUBILITIES OF PURE SALTS IN WATER AT o°. (PARTS PER 100.)

NaNO; (NH4)2504 NaCl KCl K2SO4
GPA oo TiO bay) 28.5 8.5
Na:HPO,.12H20 CaH,(PO,)2.H2O CaHPO, CaSO.4.2H2O
6.3 4 (15°) 0.028 0.241

Commercial acid phosphate consists of about equal parts of mono-calcium
phosphate and calcium sulfate. Reversion to monohydrogen phosphate
in presence of bases in the soil would further decrease the low solubility
of the acid phosphate and by double decomposition with calcium, iron
and other bases in the soil render the sodium phosphate first applied less
soluble, as pointed out by Cameron and Bell.’

Dried blood, giving soluble products at a rate depending upon the
rapidity with which bacterial decomposition proceeds, could not be
rated as having a known solubility without a study of the bacteriological
activity of the soil mixture. Tests with litmus paper showed that the
surface of the soil, neutral at the beginning of the experiment, became
acid seven or eight days after the addition of the dried blood. Soil to
which ammonium sulfate was applied became acid as quickly also.

Single applications of ammonium sulfate and sodium chloride at the
rate of 12.5 kg. per 100 sq. ft. made on December 3, 1913, produced marked
injury within a week’s time. Equal amounts of potassium sulfate, at
this time, followed by further applications at intervals of one or two
weeks, at the rate of 1.25 kg. per 100 sq. ft., produced no signs of injury
until about January 15, when a lack of turgidity became noticeable, fol-
«lowed by a gradual stunting of growth, with the more pronounced signs
appearing only after the middle of March. Signs of injury in sections
treated in the same manner with sodium phosphate became evident even
more slowly, while acid phosphate produced no apparent injury even in
the largest applications.

* The impurities in the ammonium sulfate, potassium sulfate (in this case 1.26%
of chloride as sodium chloride) and disodium phosphate are not sufficient to interfere
with the use of the solubilities of the pure substances as a rough measure of the solu-

bilities of the fertilizers themselves.
** Van Nostrand—Chemical Annual, 1910.

5

The fertilizers may be grouped into the class, easily soluble and pro-
ducing almost immediate injury; a second, moderately soluble and pro-
ducing delayed injury; and a third, difficultly soluble and producing no
apparent injury. On days of continuous sunlight a more or less pro-
nounced softness of tissue could be detected by careful observation long
before characteristic injuries became apparent.

Effects of Overfeeding with Ammonium Sulfate.—A marked softness
of tissue was the earliest sign of overfeeding with ammonium sulfate.
A complete plasmolysis took place in that portion of the stem located
two and three nodes below the bud and in the portion of the stem just
above the node, so that the stem bent completely over. The shoots first
affected were those with buds one-half to three-quarters developed. At
the same time white spots 0.25 and 1.00 mm. in diameter appeared upon
the upper leaves of these and the younger shoots. Microscopic examina-
tion of these showed the chlorophyll bearing tissue entirely plasmolyzed.

In contrast to the injury from other fertilizers, practically every flower
split.* This splitting was not caused by the pressing outward of the
petals as is usually the case, but by a weakening of the tissue at the line
joining the sepals to form the calyx cup. Later stages resulted in the
drying up of the leaf tips, and the appearance of the white depressions
upon the older leaves. The sepal tips very early became brown. Later,
pustule-like elevations about 1 mm. across appeared on them, caused
by a crystal of ammonium sulfate beneath the epidermis. The injury
from excess of ammonium sulfate was more rapid and pronounced in the
presence of lime than without it.

Effect of Overfeeding with Sodium Nitrate.—Injury followed heavy
applications of sodium nitrate within a few days, the characteristic
symptom being an even lightening of color of the foliage over the plant,
followed by drying of leaf tips and petals and withering of the plant.

Effects from Large Applications of Sodium Chloride.**—The first appear-
ance of injury from large amounts of sodium chloride was two days after
its application, a plasmolysis of the cells of the stem, causing it to lose its
rigidity at the crown. When held within supports the plants appeared
normal. Gradually, however, the plants lost their turgidity and the
chlorophyll disappeared evenly throughout the entire plant. Tests made
in the spring of 1915 with heavy applications of sodium chloride and
potassium chloride (12 kg. per 100 sq. ft.) showed the same effect from
each of them, while sodium sulfate, like potassium sulfate, showed less
injury and that only after a longer period.

* Splits is a trade term denoting flowers with split calyces.
** Sodium chloride, while not strictly a fertilizer, was used in the experiments be-

cause of its presence in considerable amounts in kainite and in some grades of com-
mercial potassium sulfate.

6

Effects of Overfeeding with Potassium Sulfate.—In earlier stages
partial wilting occurred on days of sunshine. Drying up of the tips of the
leaves and curling of the leaves upward upon their long axis followed,
with often, also, a peculiar inhibition of growth on one edge of the leaf,
with the same on the opposite edge of another portion, giving the leaf a
wavy outline.

A marked stunting of growth was observable. This affected most
noticeably the lengthening of the stem, resulting in the later shoots assum-
ing a rosette appearance, due to the leaves of normal length upon a stem
with undeveloped internodes less than an inch in length. (The inter-
node in full grown shoots is ordinarily three or four inches long.) ‘The
edges of the petals of the flowers after about the middle of January became
_ quite generally withered or crinkled. ‘Those in the center of the flower
remained closed quite tightly, while the other two or three rows opened
normally. Later, the buds remained closed, although the pistil often
pushed its way out and might be seen extending an inch above the top
of the bud.

A marked increase in exudation of nectar in the flower was found to
have caused the gluing together of the petals, and so prevented their
opening. On cloudy days very frequently a calyx cup would be found
completely filled with this exudation. The exudation was most plentiful
in the flowers from plants receiving a moderately heavy application of
potassium sulfate over a long period of time while the heavier applica-
tions caused a noticeable but less plentiful increase. A small amount of
nectar is found in normal flowers, and somewhat larger amounts in the
flowers from plants receiving large applications of sodium phosphate,
sodium chloride, ammonium sulfate, or potassium chloride, but not so
generally nor in such large amounts as in the sections treated with potas-
sium sulfate. Injury was less marked when ground limestone was added
to the soil, in contrast to the effect of liming on the production of injury
by ammonium sulfate.

Effects of Overfeeding with Sodium Phosphate.—When moderately
large amounts of sodium phosphate were added over a long period (as in
1913-14) no injury was noticeable until about the middle of March, when
a retardation of growth was evident from the decrease in height of the
plants and abnormally small buds and flowers. ‘These signs of inhibition
became steadily more pronounced until the plants were removed from the
benches, about May first. When larger amounts were used (as 12 kg.
per 100 sq. ft. in 1914-15) loss of turgidity in the plants, longitudinal
rolling of the leaves, death of the leaf tips and softness of the petals of the
blossom were evident. These signs of injury appeared, however, only

after the middle of January and then only gradually. Injury was less
when the soil was limed than when not.

Effects of Overfeeding with Dried Blood.—In none of the experiments
with dried blood did injury appear until about the middle of January.
At that time a softness of the petals and irregularity of their arrangement,
due to the partial opening of the inner and crinkling of the outer ones,
became more or less common. ‘The flowers became susceptible to brown-
ing when a drop of water from syringing lodged on a petal in a position
to be reached by the rays of the sun. The height of the plants was below
normal in the spring but rather above in the fall; the color was good.
If the applications of dried blood were not continued after signs of injury
became apparent, the plants gradually recovered. The same held true
for plants overfed with ammonium sulfate in contrast to those which had
been injured by potassium sulfate, sodium phosphate, and sodium chloride.

Effects of Overfeeding on the Mineral and Nitrogen Content of Plants.
—Effects upon the dry weight and ash are shown in Table II, the samples
being the foliage from the shoots gathered January 9, 1915.

TABLE II.—Dry WEIGHT AND ASH IN FOLIAGE.
Ash (sulfated)

Section Moist weight. per cent. of dry
No. Treatment. G. Dry weight. %. weight.
269. Check. 27.6. 17.8. 13.68.
271 T250h* 32.4 17.6 13.93
273 250 P ooo 18.3 12.89
275 500 P 30.6 18.9 14.28
277 125 K 26.1 18.4 E5537
279 250K 36.8 20.4 15.45
281 500 K 32.8 22.6 15.59
283 Check 28.2 19.2 13.19
285 125 NaCl 42.9 22.8 14.45

The increase in both values as the applications of any one fertilizer in a
series were increased is shown in the table. The higher values for plants
treated with potassium sulfate and sodium chloride over those treated
with sodium phosphate correspond to the higher osmotic pressure values
obtained from the sap of these plants as well as to the more rapid injury
from potassium sulfate.

Determination of the total nitrogen and mineral content of the ash
from various samples of plants treated with potassium sulfate gave the
following values:

*N, P and K in the tables are used to indicate ammonium sulfate, disodium
phosphate and potassium sulfate, respectively, while NaCl indicates sodium chloride

and A. P., commercial acid phosphate. The figures preceding the letters indicate the
number of grams applied weekly per 20 sq. ft. of bench space.

TaBLe III.—EFFECT OF POTASSIUM SULFATE.
Analyses. Per cent.

—0gO0©0 O_O
Treatment. Na2O. K20. SOs. N (total). P20s.
Check 1.09 5.38 DaOy, 2.58 0.72
K Ts 6.62 1.91 2.53 0.70
0.16 1.24 0.84 —O.05 —O.02

The data show an increased sodium,* potassium and sulfur content,
with practically a constant percentage of nitrogen and phosphorus.

A similar study of plants to which ammonium sulfate had been ap-
plied gave the results shown in Table IV.

Plants to which sodium phosphate was applied showed a higher phos-
phorus content, 0.60% P20; and 1.17% P2O; in a sample of 1915 in which
the calcium content was decreased (2.31 and 1.63% CaO, respectively,
in the last set of samples); the nitrogen content was increased by applica-
tions of sodium phosphate, the values 1.99%, 2.84% and 3.30% being
obtained from plants to which had been applied, respectively, none,
250 g. and 500 g. of sodium phosphate per 20 sq. ft. of bench space per
week for several weeks.

TABLE IV.—EFFECT OF AMMONIUM SULFATE.
Analyses. Per cent.

Treatment. N (total). N(by MgO). S03. P2Os.
Check 2.05 0.168 0.75 0.93
N 2.93 0.364 2.10 1.14:
0.88 0.196 Ths RS 0.21

The ratio 2N/SO; in ammonium sulfate is 28/80 = 0.351, that of total
nitrogen to sulfur increase is 0.652; and of nitrogen by MgO 0.145. The
intake of sulfur when this fertilizer is used is less than is required for the
nitrogen then, but in excess of that required to be combined with the
nitrogen determined by MgO.** Limestone was found to depress the
sulfur intake from ammonium sulfate. Since injury was greater in sec-
tions so treated, the injury is not proportional to the intake of sulfur.
The intake of phosphorus was increased by the addition of ammonium
sulfate, probably due to acidity developed in the soil.

Table V shows the total nitrogen content of some plants from Sections
264 (ammonium sulfate and lime) and 281 (ammonium sulfate). Samples

* Mayer” states that the addition of soluble potassium salts to a soil causes a
partial repiacement of the sodium.

** The author would not care to report the presence of ammonium salts in plants
not fed with it. It seems, rather, that MgO has caused some decomposition of the
organic material; the error due to this is assumed to be the same in both samples.

a A

2

were collected on April 25, 1914. Section 281 had received but one
application at the rate of 12.5 kilos per 100 sq. ft. on December 3, 1913,
while applications at the rate of 1250 g. per 100 sq. ft. were made to Section
264 at 15 different intervals of about two weeks after December 20, 191 eg
Analyses were made of upper and lower portions of the plant separately
in order to show any localization of nitrogen in the more vigorously grow-
ing portion of the plant.
TABLE V.—Tortat NITROGEN DETERMINATION ON FOLIAGE.

Sample No. Plant No. Section. Portion. _ Condition. Nitrogen. %.

I I 264-E upper half dead 4.58
. lower half dead 4.07

3 4 264-P upper half dead 7.78
4 lower half dead 5.64
5 I 264-P upper dead 6.14
6 lower dead 3.41
7 Il 264-E upper alive 6.69
8 lower alive Sew A
9 4 264-E upper half dead Teor
bo) lower half dead 334
II II-15 281-E upper dead 4.60
12 lower dead 3.02
13 16 281-E upper partially affected vb
14 lower partially affected 3.78
15 20 281-E upper half dead 4.73
16 lower half dead 2.94
17 7 281-E upper slightly affected 4.47
18 lower slightly affected Bhar

The total nitrogen content of the plants varied from once and a half to
more than twice the normal value found in the previous set. Average
values for the plants from Section 264 are 6.44% and 4.43%, respectively ;
for those from Section 281; 4.63% and 3.24%. In each case the more
vigorously growing portion contained the larger percentage of nitrogen
and the increase over the lower portion is considerably greater in the
section to which the smaller applications were made during the entire
season. No clear relation is shown between the nitrogen content and
the degree of injury. Considerable tolerance for ammonium sulfate is
shown when it was applied to the soil in quantities not heavy enough to
produce immediate, serious injury. The fact that the dead plants had no
higher total nitrogen content than those only injured is evidence that part
of the nitrogen when added in small quantities was changed to a nontoxic
form, since the dead plants were in this condition as early as March 21,
while the living ones though injured undoubtedly continued to take up
the salt in solution until samples were taken.

A series of ammonia determinations was made on the sap from ‘‘checks”’
and ammonium sulfate fed plants of the set of 12-9-14. Folin’s micro-
method for the determination of free! ammonia was used, the excess of

Io

sulfuric acid (0.01550) being titrated back with potassium hydroxide
0.02130 with sodium alizarin sulfonate as the indicator. Results are
given in Table VI.

TABLE VI.—FREE AMMONIA IN PLANT Saps.*

Nitrogen.
Sample No. Treatment. Appearance. Mg. N per cc.
5 check normal none
8 250 N normal 0.1834
7 500 N normal 0.1372
2 1000 NV slightly injured 0.6390
I 1000 NV badly injured 1.0560

The white spots on the leaves of plants treated with ammonium sulfate,
and of crystals imbedded beneath the epidermis of the sepals were studied
by microchemical methods.‘

I. January 21, 1914. Plant Number 4, Section 281, White Enchantress.
Plant apparently normal. A drop of sap from the stem of a shoot was
treated with a drop of ammonia-free hydrochloric acid and chloroplatinic
acid, and evaporated at room temperature under a loosely covering watch-
glass. A few crystal masses, tetrahedral and often aggregated in shape
of a cross, appeared. They were yellow in color. Sap from Number 8,
somewhat injured, and Number 12, badly affected, gave these characteristic
crystals, also.

2. A section of the leaf showing white blotches was immersed in chloro-
platinic acid after removal of the epidermis and allowed to remain over-
night. Large and perfect crystals appeared, arranged usually around
the injured spot, never in it. They were insoluble in 95% alcohol which
removed the excess of chloroplatinic acid.

3. A drop of sap from plant Number 4, Section 281 was distilled with a
pinch of sodium carbonate over a micro-burner and the distillate caught
in a hanging drop of hydrochloric acid in a cover glass placed on a glass
ring above it. Treatment as above gave small, yellow tetrahedra in-
soluble in 95% alcohol.

Ammonium salts were evidently present and apparently caused plas-
molysis of certain of the chlorophyll bearing cells. Why injury of this
type is caused by ammonium sulfate in contrast to the even lightening
of the color of the whole leaf by the other soluble salts, sodium nitrate
and sodium chloride, is not known.

Nitrate determinations according to the phenolsulfonic method of
Mason?! were made upon the sap of a “‘check’”’ and an ammonium sulfate
fed plant from the set of March 9, 1915. ‘The values of 0.01 and 0.40
mg. N as nitrate per cc. of sap, respectively, showed that nitrification was
proceeding in the soil although it was quite strongly acid.”

* Tn earlier stages of feeding with ammonium sulfate, samples have been taken in
which no NH; was detected by this method.

_— oo se

II

Total solids and ash were determined on the sap of the set of 12-9~14.
The results, given in Table VII, are calculated to milligrams per cc. of
sap.

TABLE VII.—Torat Souips anp Asx oF Sap.

; Total solids. Ash.*
Sample No. Set date. Section. Treatment. Mg. per cc. Mg. per cc.

2 12-9-14 291 : 1000 N 91.9 re

3 293 1000 K 104.9 19.2

5 289 check e638 0.8

6 261 check 62.1 LQ

7 265 250 N 63.6 TKO

8 267 500 N 79.9 15.1

9 7 125 K 64.3 16.1

10 279 250 K 69.9 172

II 281 500 K Fi Sy 1 ei

12 283** check Gfele hi 15.0

I I-9-I5 269 check 84.0 Speck

2 271 125 P SI 27, TS 2

“) 273 250 P 86.7 £333

4 275 500 P 93.0 PS).1

5 277 125K 92.3 13.4

6 279 250 K 106.3 20.1

5) 281 500 K 33). 7 20.0

8 233 "* check 105.1 14.1

The average total solids content of the sap was 85.1 mg. per cc. and the
ash content 14.9 mg. The influence of the fertilizer applications
is seen in the increase in both values as the applications of any
fertilizer were increased in a series of sections. Sample 3 of the first set
and 6 and 7 of the second, all of which were from plants to which large
applications of potassium sulfate had been made, showed particularly
high values.*** The first set of data was obtained by drying the samples
in a Sargent electric oven at 60-70°, the second in a vacuum oven heated
to 50° for 12 hours. The actual value for total solids depended on the
length of heating but experiments with both sets of data given showed the
same relative values after several successive heatings.

* Ash determinations upon the sap were made by careful incineration of the solids
in 1 cc. of sap in platinum dishes over a low flame to prevent mechanical loss of particles
of the ash. The low chloride content obviates the danger of volatilization of potassium
chloride by high temperatures.

** For some reason total solids and ash determinations always ran higher in sap
from plants in Section 283 than from those in other “check” sections. The same dis-
crepancy is seen in the osmotic pressure data for these two sets.

*** The determination of total solids with accutacy is not possible on account of the
uncrystallizable solutes in the sap, and on this account the mean molecular-weight
calculations which often accompany osmotic pressure data were not made. Drying
on the water bath was found to cause charring of the sap from plants which had been
treated with ammonium or potassium sulfate. The first showed a higher acidity value,
the second a higher sugar content.

I2

Determinations of sodium and potassium in the ash from sap obtained
on January 9, 1915, from plants treated with potassium sulfate, were made
in order to show the increased intake of potassium. Similarly, determina-
tions of phosphorus were made upon the sap from plants fertilized with
disodium phosphate. The results. calculated to milligrams per cc. of
sap, are given in Table VIII.

_TasLe VITI.—MIneraL ContEeNT OF Sap.

Na2O. K.20. Mg: P207.

Sample No. Section. Treatment. Mg. Mg. Mg.
9 277 125 K 1.4 9.4
10 279 250 K T3 10.1
II 281 500 K 1.3 10.1
12 283 check re 8.4

I 269 check Le Re ee TES

2 271 7S) Ve Sot nine 6.1

3 273 2500k cant, ee 7.5

4 275 500 P sae ee 9.6

Effect of Overfeeding on Osmotic Pressure of Sap.—Sap was expressed
from the stems of shoots after freezing them with an ice-salt* mixture,
and the lowering of the freezing point determined by the method of Harris
and Gortner** of allowing supercooling until the solution froze and cor-
recting the value of A’ obtained by the formula

A = A’—o0.0125 uA’
where A’ is the maximum temperature attained in the system and u the
difference between this value and the minimum temperature. The
relation between A and the osmotic pressure given by Lewis!® in the

approximate equation
a7 = 12.06 A

was used in calculating the value for 7.

Description of Experimental Method.—Choosing a time when for two
or more hours previous no appreciable draft had been stirring the air in
the greenhouse, from four to eight shoots at the same stage of growth
were removed from each of the sections of plants and quickly taken to

* Care was taken to select samples from the check and affected plants at the same
time of day and shoots in the same stage of growth were taken, to insure freedom from
variations in osmotic pressure due to differences in location and illumination, while
the fact that the sections studied were usually adjacent obviated the difficulty that
differences in temperature change the osmotic pressure of plants. See Dixon and
Atkins,!! Atkins,* Ewart,!3 Drabble and Drabble,!2 Cavara.®

** The method in general was an adaptation of that recommended by Gortner
and Harris.‘°*® André! and also Dixon and Atkins!! have shown that successive por-
tions of sap expressed from unfrozen tissue become more concentrated, while the latter
have shown that the sap from frozen tissue always has a lower freezing point than that
from unfrozen, and that successive portions gave nearly identical lowerings, leading
to the conclusion that sap so expressed is representative of that originally within the
tissue.

13

the laboratory. After removal of the foliage from the stems, they were
broken at the nodes and placed in hard glass test tubes (25 mm. X 150
mm.), stoppered with rubber stoppers and sealed with oil paper and rub-
ber bands. Freezing was produced by the use of the ice and salt bath,*
giving a temperature of —15° or lower and allowing the tubes to remain
in the refrigerator overnight. The tubes were then removed from the bath
and after the walls had been cleaned with distilled water and wiped dry,
the portions of shoots were removed, thawed gradually, and the sap ex-
pressed by pressure from the screw of a tincture press set perpendicular
to the wall upon two pieces of */s inch plate glass. After a first expression,
the shoots were rearranged and pressure again applied. The sap was
filtered through an S. & S. 589 filter—with a watch glass over the funnel
to minimize evaporation—into a small test tube; a drop of xylene was
added as a preservative and the tubes placed at once in a refrigerator, at
about 10°. The sap after filtration was usually a clear, brown liquid
without sediment.

As soon as convenient the freezing-point determinations were made.
A thermometer was used having a bulb about 5 mm. by 35 mm., the mer-
cury tube enclosed in a hollow jacket, and graduated to —6.5° in tenths ©
of degrees, upon which, by the aid of a lens, hundredths of a degree could
be read without danger from parallax. A stirrer of platinum wire and
the thermometer were placed in the 5 cc. of sap contained in a test tube
of Bohemian glass (15 120 mm.) and the whole cooled to about +2°
in an ice and salt bath in a beaker. ‘The tube was wiped free from water
and placed within a hard glass test tube (25 mm. X 150 mm.) set two-
thirds way into the ice and salt-freezing mixture. It was found saving
of time to place this bath in a Dewar bulb, with inside diameter of 35 X
130 mm.; the top was closed with a piece of cork; the bath so arranged
remaining effective for three hours or more of use. During the entire
cooling, the sap was constantly stirred to prevent its freezing about the
sides of the tube. The lowest temperature obtained was read to one-
tenth, and the maximum, by the aid of a lens, to one-hundredth degree.
The tube was removed to a beaker of water, and after the temperature
had risen to about 10°, the determination duplicated to within o.o1°,
usually without difficulty. on the first trial. A typical determination
gave the following values:

A’ = 1.28 u = 4.12 A = 1,214
No Tr 27 u = 3.43 Av = 2: 216
Average 1.215 from which = 14.64 atmospheres.

* It was found convenient in case less than a dozen tubes of material were frozen’
to place the ice and salt bath in one or two one-liter Jena beakers. In this way the
ice can be packed about the upper portions of the test tubes, and the beakers, with five
or six test tubes in them, are narrow enough to keep the tops of the test tubes from
touching the solution.

14

TaBLE IX.—OsmotTic PRESSURE DETERMINATIONS.
Sample

Date. No. Section. Treatment. PNG u. A. T.
II-12-15 I 291 1000 N 1.30 By2r I.210 14.60
2 293 1000 K | 4.03 1.261 D520
3 295 1000 P Teng 5.18 Tkos 14.41
4 289 check 1.15 3.90 1.054 2271
5 269 check I.00 Taro 0.946 11.41
II—20-14 I 291 1000 N 1.33 5.67 1.196 14.42
2 293 1000 K 1.50 3.40 1.396 16.84
3 295 1000 P 1.10 4.80 0.994 11.99
4 289 check | ate) 5.80 1.078 13.00
5 283 check 1.18 2.87 1.098 13.24
5 | 283 check Vey 4-43 1.160 13.99
12-9-14 I 291 1000 N 1.66 5.34 1.513 18.24
(10 A.M.) 2 291 1000 N 1.43 4.78 1.305 Tg
g 293 1000 K 1.40 5.30 1.267 15.25
5 289 check 0.95 4.55 0.856 10.34
6 261 check 0.99 201 0.901 10.86
4] 265 250 N Lato 5.10 0.990 11.94
8 267 500 N 1.28 5.40 T7174 14.16
12-9-14 9 277 125 K 1.05 3.75 0.962 11.60
(4 P.M.) 10 279 250 K 1.18 4.82 0.973 T1273
II 281 500 K 1.18 4.32 1.076 13.01
12 283 check 1.06 4.14 0.967 11.68
I-9-15 I 269 check 1.20 4.00 I.100 13.24
2 271 T25, 2 123 4.62 1.169 14.08
3 273 250 P Ege 4.98 1.178 14.20
4 275 500 P 1539 3.81 1.284 15.50
5 277 125 K 1.35 2.65 1.265 15.29
6 279 250 K 1.58 4.92 1.448 17.49
7 281 500 K 1.87 4.63 Te 22 20.76
8 283 check T7285 4.92 LOL 14.04
9 285 125 NaCl 1.88 2292 177i 21.40
10 287 500 A. P. 1.48 5.52 1.338 16.13

Discussion of Results—No comparison can be made between the
values for the osmotic pressure determined in successive sets on account
of variations due to temperature, physiological scarcity of water, etc.,
but the values obtained from plants in adjacent sections at the one time
are regular enough to be comparable.

From the values for osmotic pressure of Samples 7, 8, 2 and 1 of the set
of 12-9-14 the conclusion was drawn that the osmotic pressure within
the plants increased as the quantity of ammonium sulfate applied to the
soil was increased. Samples 2, 3 and 4, and 5, 6 and 7 of the set of 1-9-15
gave similar results with increasing applications of sodium phosphate
and potassium sulfate. The values obtained from the application of
sodium phosphate were in every case lower than those obtained from appli-
cation of equal quantities of potassium sulfate or ammonium sulfate. The

15

samples taken on 11-12-14 and 11-20-14 gave higher values for the sap
from plants overfed with potassium sulfate than those treated with am-
monium sulfate, but later in the year in the set of 12-9-14 (Samples 1
and 2) the relative values are reversed.

‘In the set of 12-9-14 plants treated with potassium sulfate at the rate
of 1000 g. per section per application were still apparently normal, al-
though the osmotic pressure amounted to 15.25 atmospheres, while plants
treated with one-half this weight of ammonium sulfate possessed an os-
motic pressure of only 14.16 atmospheres and showed signs of injury.
Injury, on the other hand, had not appeared on plants treated with am-
monium sulfate (250 g. per section per application) when the osmotic
pressure amounted to 12.42 atmospheres as compared to 11.34 atmos-
pheres in the adjacent “check” section (12-9-14—I0 A.M.).

The higher value of Sample 1 over Sample 2 (of the set of 12-9-14—
10 A.M.) was correlated with a greater degree of injury by the ammonium
sulfate. Injury appeared on the plants from sections to which potassium
sulfate was applied, only when an osmotic pressure of over twenty atmos-
pheres was reached (1-9-15), and an osmotic pressure value up to 15.50
atmospheres was found in plants on soil treated with sodium phosphate,
without injury being apparent. he determination of the value on the
sap from plants treated with acid phosphate gave 16.11 atmospheres,
yet these plants exceeded in size and vigor those to which no fertilizer
was applied (1-9-15)- The conclusion to be drawn from these facts
is that, with a single fertilizer, injury from overfeeding becomes apparent
when a certain osmotic pressure is reached, but that this value is different
for different fertilizers.

The injury from applications of sodium chloride at the rate of 125 g-
per section per application, occurred at approximately the same time,
was very similar to, and was of about the same degree as that from ap-
plications of potassium sulfate, in four times these quantities. The rela-
tive osmotic pressure values are given in Samples 9 and 10 (1-9-15).
The solubilities of these salts, as pointed out on page 2785, at o° are
35.7 and 8.5, respectively, giving a ratio roughly of 4 to I.

Effects of Overfeeding on the Total Acidity of the Cell Sap.—Reaction
tests with litmus paper showed that the soil receiving no fertilizer or
only manure was neutral or slightly alkaline in the fall, and that a gradual
change to slight acidity took place during the winter. Commercial
acid phosphate, dried blood and ammonium sulfate upon the soil each
increased the total acidity,* the first one immediately after application,

* It is not likely that the hydrogen-ion concentration of the soil solution was greatly
increased by addition of commercial acid phosphate, since the formula used in its prep-
aration prevents the presence of free sulfuric acid by providing a slight excess of tri-
calcium phosphate. Salm,?3 using a hydrogen electrode apparatus, found [H] = 3.3 X
10~° for the di-hydrogen sodium phosphate at 18° in o.1 N sol.

16

the latter two within about a week’s time. In the case of these fertilizers,
the surface of the soil became acid after the lower portions. When di-
sodium phosphate was applied, the surface of the soil became alkaline
to litmus, the deeper parts becoming alkaline more slowly. ‘Tests on
Section 275 (500 P) on February 18, 1915, and on 291 (1000 P) on March
22, 1915, showed that the soil at each successive inch to the bottom of the
_ bench, was alkaline to litmus. In so far as could be determined by this
method, applications of potassium sulfate and of sodium chloride did not
change the reaction of the soil.* Hence an opportunity was given to study
the effect, upon the acidity of the cell sap, of fertilizers producing increased
acidity in the soil, alkalinity, and no change in reaction, and upon the re-
lation the changes bore to injury from overfeeding with the fertilizer.

Determinations were made by titrating at about 15° with COp-free
KOH, approximately 0.02 N, 1 cc. portions of sap diluted to 6 cc. with
CO,-free water, using phenolphthalein as the indicator. Results are cal-
culated as cc. of normal acid per cc. sap.**

TABLE X.—Acrpity oF PLANT S&Ap.***

Sample Condition
Date. No. Section. Treatment. of plants. Ce. N acid.
12-10-14 I 291 1000 N affected 0.03068
2 293 1000 K normal 0.02492
3 295 1000 P normal 0.05490
4 289 check normal 0.02048
5 261 check normal 0.02090
6 265 250 N normal 0.02238
7 267 500 N affected 0.02728
8 277 Wat 1S normal 0.02088
9 279 250K normal 0.02002
10 281 500 K normal 0.02130
II 283 check normal 0.02130
I-14-I5 12 269 check normal 0.01977
13 271 1250 e normal 0.05035
14 273 250 P normal 0.06438
15 275 500 P normal 0.07415
16 DG fa} 125K normal 0.02319
17 279 250 K normal 0.02039
18 281 500 K affected 0.02422
19 283 check normal 0.02252
20 285 125 NaCl affected 0.01870
21 287 500 A. P. vigorous 0.06981

* See, however, Maschaupt.?9
** For memoir on acidity in plants, see Astruc.?

*** Boiling a solution of CO, in distilled water under diminished pressure by warm-
ing the test tube with the hand was found completely to remove the COz. Similar treat-
ment of sap gave identical values for acidity before and after. Hence, the acidity
was not due to dissolved COs.

17

Acidity values remained about the same when potassium sulfate was
applied, but increased after applications of acid phosphate, ammonium
sulfate or disodium phosphate, being proportional in each case to the
amount put on the soil. The increased total acidity following applications of
disodium phosphate (which is alkaline to phenolphthalein) was unexpected
and a more detailed study was made of the sap from these plants. Ether-
soluble acids were absent and none of the phosphate was extracted by
moisture-free ether. Phosphate was determined in 1 cc. portions of
Samples 12-15 and the total acidity of the solution calculated on the as-
sumption of the phosphorus being present (1) as orthophosphoric acid,
and (2) mono-alkali phosphate,* the values being given in Table XI.

TABLE XI.—Acipity oF Sap BY TITRATION AND CALCULATION.

Acidity.
Sample eee
° Treatment. Mg2P207. As H3POs. As XH2POs.. By titration.
12 check 0.0015 0.02692 0.01346 0.01977
13 To5ee 0.0061 0.10768 0.05384 0.05035
14 250 P 0.0075 0.13460 0.06730 0.06438
15 500 P 0.0096 0.16348 0.08174 0.07415

The values calculated as XH2PO, agree more closely than those for
H;PQ,., pointing to the presence of the phosphate as mono-alkali phos-
phates. Subtraction of the ‘“‘check’’ value for MgeP.,O; from each
of the other values to obtain the increase in phosphate intake due to
applications of disodium phosphate and comparison of the titratable
acidity calculated from these results with the excess of acidity of the solu-
tions over that of the “check” gives the following results:

TABLE XII.—Acipity AND PHOSPHORUS CONTENT DUE TO OVERFEEDING.

Increase in P2Os.
-— Titration. Ratio.

(1) As MgeP207. (2) As MgmH. (3) As MgmH. (3)/(2).
0.0046 0.03999 0.03058 0.765
0.0060 0.05388 0.04461 0.827
0.0081 0.07276 0.05438 0.747

The ratio between the value of H determined by titration and by the
gravimetric method at 15° was determined to be 0.905, so that the ratios
obtained are in the same direction, although the lower values for the sap
indicate that some of the phosphate may have been present as the mono-
hydrogen phosphate.

This method was applied to the problem of determining the salt in form of which
phosphorus enters the plants. In every case increasing applications of disodium phos-
phate gave higher acidity values. When brown rock phosphate was used (nasturtiums
grown in sand culture with Hopkin’s nutrient solution omitting phosphorus after the
first application) a regular increase up to a maximum in size of plants followed by a

* Two hydrogens of orthophosphoric acid and one of monosodium phosphate
when the solution is concentrated at o° and phenolphthalein is the indicator. At
higher temperatures, hydrolysis of the salt increases the alkalinity of the solution.

18

decrease was obtained, without a consistent variation in the acidity of the sap. Rock
phosphate apparently is not taken into the plant as mono-calcium phosphate.

Reaction of the soil to litmus paper was determined from time to time.
After the first applications of sodium phosphate the soil reacted alkaline
to litmus on the surface, with decreasing alkalinity or acidity as the dis-
tance below the surface increased. On March 22, 1915, Section 295
(to which applications of 1000 g. of sodium phosphate had been made)
was found to have an alkaline reaction to litmus paper when tested for
each inch of soil down to the bottom of the bench (5 inches). ‘Two
shoots each from plant Number 4, badly. injured, and plant Number 12,
apparently normal, were taken and the sap expressed without previous
freezing. ‘The sap reacted acid to phenolphthalein in each case.

The power of soils to absorb bases from salts is well known.* With
this in mind, a liter of solution of disodium phosphate was made up with
carbon dioxide-free water, and aliquot portions titrated with standard
sulfuric acid to a faint rose coloration, using phenolphthalein as the indi-
cator. Six carnation cuttings, rooted in water, were cleansed by repeated
washing with distilled water and floated on the surface of 500 cc. of the
solution by placing them in holes of a paraffined cork. ‘They were placed
in the greenhouse for six days, covered with a large bell jar and shaded
during the daytime. The cuttings were taken out, the solution care-
fully rinsed off and after removal of the roots the remainder of the shoots
was frozen, the sap expressed, and 1 cc. portions titrated with standard
alkali, using phenolphthalein as the indicator. Comparison was made
with the acidity of the sap from cuttings taken from the cutting bench
and prepared as in the former case for sap expression.

STRENGTH OF SOLUTION 2 G. NazHPO,.12H2O PER LITER.

Titration of 10 ce. portions Titration of plant sap.
HeSOs, (0.01550 N). KOH (0.02130 N).
eS os es ee ae eee
ly (2). (1) Check. (2) Treated.
0.32 cc. O31 ce: 0.92 cc. Teg ,ee

0.0048 cc. N alkali per ce.

In the absence of soil, the sap had become more acid when the plants
were grown in the disodium phosphate solution, hence the increased
acidity could not be attributed, at least entirely, to the absorptive power
of the soil for bases.

Effect of Large Applications of Potassium Sulfate on Carbohydrate
Content of Sap and Foliage.—The increased exudation of nectar and
gluing together of the petals in the flowers on plants which had been treated
with large amounts of potassium sulfate has been listed among the charac-
teristic signs of overfeeding with this fertilizer (page 6). An attempt
was made to determine the cause of this increased flow.

‘The amount of nectar present in an affected flower amounted to as much
as 1 cc. in the spring of 1912-13, when applications of potassium sulfate,

19

moderate when compared with those used in 1914-15, were made weekly
during the season October to May. In 1914-15 the flow was not so plenti-
ful, although noticeably greater than in the ‘‘check’”’ flowers. In the for-
mer year, the nectar was a brownish liquid with a sweet and bitter taste,
miscible with water, while in the latter year it was a clear, colorless
liquid. It had-a sweet taste, and was neutral to litmus and phenolphthal-
ein. It charred on ignition on a platinum foil, with the odor of burnt
sugar, leaving a small amount of ash which was alkaline to moist litmus
paper and to phenolphthalein. Sodium and potassium flame tests were
positive, calcium doubtful. No indication of tannin was given by tests with
neutral ferric chloride and with potassium ferricyanide and ammonia.
A solution made by washing off the nectar with distilled water reduced
Fehling’s solution. A heavy osazone precipitate of bright yellow color
was thrown down upon heating it in a boiling water bath with phenyl-
hydrazine, acetic acid and a crystal of sodium acetate, after three minutes’
boiling. Ten minutes’ boiling increased the amount. A much heavier
osazone precipitate was given after a few minutes’ boiling with hydro-
chloric acid, and a portion of the solution inverted by the Clerget method
gave a heavier osazone precipitate than a similar amount before inver-
sion. ‘The rotation in a 1 dm. tube of 1.5° Ventzke was changed to 1. 18°
V. after the Clerget inversion. Hence, glucose and sucrose were present.
The precipitate formed in the hot solution was filtered off and the filtrate
again boiled till no further precipitate separated. On cooling the fil-
trate a further precipitate of sodium acetate and osazone separated.
This osazone possessed a roset structure characteristic of maltosazone,
and was soluble in the boiling solution and reprecipitated from it on
cooling as is maltosazone. Not enough of the precipitate could be ob-
tained after recrystallization for a melting-point determination.* Tests**
made with a guaiacol solution and neutral hydrogen peroxide gave a nega-
tive test with the exudation, but an equally intensive color with sections
of petal, ovary, leaf and stem of both normal and affected plants. Neither
of the reagents used alone gave a reaction, Microscopic examination of
the lower, plasmolyzed portions of the petals showed the cell walls intact
and of normal thickness. It was concluded from this that the increased
amount of sugar was not due to breaking down of these cell walls, but was
an exudation. Experiments were then undertaken to compare the sugar
content of the sap expressed from the stems of the plants not fertilized and
of those receiving applications of potassium sulfate. Evidence that a
larger amount of sugars was present in the sap of the latter plants was

* Brown and Morris® used 200 g. of leaf tissue in order to obtain enough for prep-

aration of maltosazone.
** Griiss!® believed gummosis might be caused by an excess of diastatic enzyme

and used this reagent as a means of detecting it.

20

found during the determination of total solids of the sap (vide supra),
when the residue from this sap was of greater weight and charred at a
lower temperature than that of the check.

The comparative optical rotations* and copper-reducing powers of
sap from ‘‘check’’ sections and those which had received applications of
potassium sulfate are shown in Table XV.

TABLE XV.—OptTICAL ROTATION AND CU-REDUCING POWER OF SAP SOLUTIONS.

Rotation Reducing power.
circ. degrees. Mg. CuO.

Date. Treatment. Orig. Hydrolyzed. Complete. Orig. Clerget. Complete.
I-9-15° check OgGie 0.83

125 K 1.91 125

250 K 1.42 0.97

500 K 1.49 Deol
2-10-15" check Bee 1.207

K 3.51 De35 IEE aang: pad eae

2-17-15" check 2how I 53 0.67 556 1434 1654

250-500 K 320 2.28 0.79 4760.5 1461 1976
3-9-157 check 2.43 1.43 1.06 521 1276 (1282)

250-500 K 3.00 1.91 1.34 522 1273 1438

In view of the work of Davis, Daish and Sawyer,’ it seems possible,
though not proven, that the quantitative relationships of the sugars
in expressed sap may not represent the condition within the living tissue.
The consistently higher values obtained by both methods of estimation,
showed, however, that the application of potash to the soil had resulted
in an increased carbohydrate production, in a more rapid hydrolysis of
starch, or in a greater permeability of the cell membranes in the meso-
phyll tissue, so that a Jarger amount of sugar was found within the conduc-
ing and storage tissues.

Leaf tissue (Set 2-10-15) dried at 50-70° was extracted with 80%
alcohol (1 g. pptd..CaCO; being added to neutralize acids present) and
the extracts, after removal of alcohol, cleared with 5 cc. neutral lead ace-
tate, 1 cc. basic lead acetate and alumina cream. ‘The extracts from 7 g

* A. Schmidt and Hausch half-shadow polariscope, with tubes 4 dm. long, was
used. CuO values were obtained by using Defren’s!® solution, the copper being de-
termined by Low’s method (Treadwell and Hall, p. 682).

“5 cc. sap diluted to 50 ce. cleared with 5 cc. basic lead acetate (sp. gr. 1.115)
and an excess of alumina cream.

* 20 cc. sap diluted to 100 cc. cleared with 10 cc. basic lead acetate and alumina
cream.
“ro ce. sap diluted to 100 ce. with 5 cc. basic lead acetate and alumina cream.

# to ce. sap diluted to 100 cc. with 2 cc. basic lead acetate and alumina cream.

° Hydrolyzed 24 hours with 10% o.5 N HCl at 70°.

4 Clerget inversion.

’ Inversion for 3 hours in boiling water bath of 25 cc. soln. 121/, cc. water and
2.5 ce. HCl gp. gr. 1.19.

20

made up to 100 cc. gave values shown in Table XVI. A trace only of
pentoses was found in the extract.
TaBLE XVI.—SuGaR DETERMINATIONS IN EXTRACTS.
Cupric-reducing power.
Mg. CuO.

Section. Treatment. Original. Clerget. Complete.
268-270 check 398.0 1656.8 1933.6
277 125 K 652.8 1873.6 1990.4

The results are similar to those in Table XV.

Examination was made for starch in carnation leaves taken from the
plant after a day of sunshine by boiling them for some time in alcohol,
then in water, and testing leaf sections with an alcoholic solution of iodine;
starch was found to be plentiful. Comparative determinations of the
starch content* were made upon the residues from sugar extractions, using
a diastase solution prepared by extraction of ground malt with mono-
sodium phosphate solution at ice-box temperature, but not dialyzed.**
Fifty cubic centimeters of water were added to the residue and the starch
gelatinized by boiling for five minutes, with continuous stirring. After
cooling to’60°, 5 cc. of the diastase solution were added with a pipet and
digestion allowed to proceed for an hour. The mixture was again heated
to boiling and 5 cc. of diastase again added and after an hour the mixture
- was filtered and washed thoroughly. The maltose in the filtrate was
hydrolyzed to glucose by the modified Sachsse method and glucose deter-
mined with Fehling’s solution, correction being made for maltose in the
diastase solution. The values obtained for samples from sets of 2-10-15
and 2-17-15 are shown in Table XVII.

TABLE XVII.—SrarcH CONTENT OF CARNATION LEAVES.
Starch per cent.

rere eee

Treatment. 2-10-15. 2-17-15.
check 272 3.44
K 1.94 3.09

A lower starch content in ‘‘check’’ tissue is indicated by the results.
While these analyses were not made over a long enough period to form
a basis for a conception of the effect produced by potash upon carbohydrate
production and transformations, the higher sugar with lower starch
content is interesting in view of the work of Sherman and Thomas** upon
the activating action of potassium sulfate upon diastase.

Summary.

_ The purpose of the investigation was to determine the effects upon the
plants of large applications of certain commercial fertilizers to the soil
on which carnations were grown.

* Brown and Morris® state that preliminary washing with cold water as in the

O’Sullivan method, is unnecessary in Tropaeolum majus.
** Sherman and Schlesinger, J. Am. Chem. Soc., 25, 1619 (1913).

22

The injuries characteristic of an excess of each fertilizer are recorded
from observations made in the greenhouse.

Determinations of dry weight and ash made upon the foliage of the
plants, showed an increase in both values with increased applications of
the fertilizers.

A sufficient number of determinations of the mineral constituents of
the foliage was made to show the increased content of the fertilizing salts
in the plants after large applications of them to the soil.

Total nitrogen determinations made upon plants in different stages of
injury showed an increased intake of nitrogen when ammonium sulfate
was applied but an acquired tolerance by the plant when successive small
applications were made. Injury from ammonium sulfate is not propor-
tional to the total nitrogen content.

The sap was expressed from the stems of the plants after freezing to
render the plasma membrane permeable to the contents of the cells.
Osmotic pressure determinations made upon this sap proved that with each
fertilizer used the degree of injury varied with the osmotic pressure,
but that not the same degree of injury was caused by different fertilizers
at the same osmotic pressure. Injury is not a result of increased osmotic
pressure exclusively.

The increase in the osmotic pressure in a series of plants on soil receiv- °
ing increasing applications of commercial fertilizers was accompanied by an
increase in the total solids and ash of the sap and in the amount of the
fertilizer taken up by the plant.

Determinations of total acidity showed an increase in the total acidity
of the sap of plants fed with ammonium sulfate, disodium phosphate and
monocalcium phosphate, when phenolphthalein was used as the indica-
tor.

The relation between the increase in total acidity and in the phosphorus
content of the sap when the plants were fed with disodium phosphate
proved that the phosphorus was taken in the form of dihydrogen phos-
phate, due, as was shown, not entirely at least to absorption of the base
by the soil but to the selective action of the plant. Applications of potas-
sium sulfate had no effect upon the acidity of the sap.

The sap from the stems of plants grown on soil to which large applica-
tions of potassium sulfate had been made showed a higher total sugar
content, the same results being obtained with extracts of foliage. The
starch content of the foliage of such plants was lower. ‘These data indi-
cate a more rapid hydrolysis of the starch in the foliage in the presence of
an excess of potassium sulfate. The increased exudation of nectar in the
flowers of these plants probably resulted from this increase in sugar con-
tent.

23

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rend., 143, 972 (1906).
2. Astruc, A., “Rescherches sur l’acidité vegetale,” Ann. Sci. Nat. Botan., [3]
17, I (1903).
3. Atkins, W. R. G., “The Osmotic Pressures of Some Plant Organs,” Proc.

Soc. (London), 82B, 463 (1910).

4. Behrens, H., “A Manual of Microchemical Analysis,’”’ p. 138 (1894).

5. Brown, H. T., and Morris, G. H., “A Contribution to the Chemistry and
Physiology of Foliage Leaves,” J. Chem. Soc., 63, 29 (1893).

6. Cameron, F. K., and Bell, J. M., ‘““The Mineral Constituents of the Soil Solu-
tion,” U. S. Dept. Agr., Bur. Soils, Bull. 30, 42 (1905).

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9g. Davis, W. A., Daish, A. J., and Sawyer, J. C., “Carbohydrates of the Man-
gold Leaf,” J. Agr. Scz., 7, 255 (1916).

10. Defren, G., ‘“The Determination of Reducing Sugars in Terms of Cupric
Oxide,” J. Am. Chem. Soc., 18, 749 (1896).

11. Dixon, H. H., and Atkins, W. R. G., ‘‘Methods of Extracting Sap from Plant
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(1907).

13. Ewart, A. J., ‘“The Ascent of Water in Trees,’ Trans. Roy. Soc. London, 198,
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17. Hall, A. D., Miller, N. H. J., and Gimingham, C. T., “Nitrification in Acid
Soils,’ Proc. Roy. Soc. (London), 80B, 196 (1908).

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URBANA, ILL.

BIOGRAPHY.
he author received his early training in the public schools of Paris,

_ 1910-1911, Instructor in Chemistry and Physics, Urbana, IIl., High
School.

IgI I-1912, Assistant in Chemistry, Agricultural Experiment Station,
University of Illinois.

1912-1914, Assistant in Floriculture, University of Illinois.
1914-1915, First Assistant in Floricultural Chemistry, University of
Illinois.

~The author is a member of Sani Xi, Phi Lambda Upsilon, Gamma
pha, and the American Chemical Society.

LIBRARY OF CONGRES

mA