yearn! He
See Y

THE TRANSLOCATION OF CALCIUM
IN A SOIL

A THESIS

PRESENTED TO THE FACULTY OF THE GRADUATE SCHOOL

OF CORNELL UNIVERSITY FOR THE DEGREE OF

DOCTOR OF PHILOSOPHY

BY
BENJAMIN DUNBAR WILSON

FEBRUARY, 1918

Reprinted from Memoir 17, December, 1918 of Cornell University Agricultural
Experiment Station

Fe ae ae

CONTENTS

MINCE SIIB 2) Foe Se psc nce oe ou as wae ae a eee ee
IER RD tr Se See Sa a ss Bind ns abe S hea ee Bae
Plan of the investigation
REPENS LMA ta, ai. else's YS yee ah o So ae
Method of placing soil in pots
PRUE OE NCE PN E58. Soca" so ncaitls ele didi «dows dle bon ee ee
IT SERINE fe os oda eehln fd aon 8 MGS Sees dol Qa GER
Bicarbonate (HCO;) content of the drainage water........
ENON te ek eS eo no ok My Seige, OS ee
Method of sampling pots for analysis of calcium
Interpretation of analytical data
Me CTUMICHG Lo 6 cb a Se Sey Cosd ee ok os se le
em eee periments 2 aNd 3.0.0. oo. ee es ols

Acknowledgment
Literature cited

205

PAGE

299
301

306
308

321
322

THE TRANSLOCATION OF CALCIUM IN A SOIL
BENJAMIN DuNnBAR WILSON

The presence of calcium in soil is of extreme importance. The action
of this element, when applied in different chemical combinations to soil,
has been investigated extensively. In spite of the fact that much has
been written on the subject of calcium in soil, it is evident from a review
of the literature that the movement of calcium in soil has received but
little attention. Definite information in relation to the translocation
of calcium in soil, under carefully controlled laboratory or field condi-
tions, is unsupplied.

The present investigation was undertaken in an attempt to answer the
following questions: (1) Does the calcium applied to a soil move down-
ward or does it remain in the upper few inches of soil? (2) If the calcium
does move downward, to what extent does it move?

REVIEW OF LITERATURE

The only study that has been made on the downward movement of
calcium in soils under controlled laboratory conditions, so far as the
writer has been able to discover, is that of Broughton (1912).1. In that
experiment the movement of calcium thru sandy, loam, and clay soils
was determined, the calcium being applied in different forms. It was
found that the movement of calcium thru a soil was governed largely
by the physical constitution of the latter, the calcium salts diffusing most
rapidly thru a sandy soil, less rapidly thru a loam soil, and only slightly
thru a clay soil. Some of the differences which the author reports in the
movement of calcium, resulting from the different treatments that were
used, might have disappeared had the treatments been repeated a greater
number of times; also, the method employed for sampling pots at different
intervals necessitated a disturbance of the soils within the pots, which
may have resulted in some mechanical movement of calcium.

Several investigators have endeavored to determine the translocation
of calcium in field soils by comparing the quantity of calcium found at

1 Dates in parenthesis refer to Literature cited, page 324.

299

300 BENJAMIN DuNBAR WILSON

different depths in soils that had received an application of calcium in some
form with that in other soils of the same type that had not been treated
with any form of calcium. McIntire (1913) analyzed a silty loam soil
for calcium at different depths from plats that had received large appli-
cations of either calcium oxid or calcium carbonate for a period of thirty
years. From a comparison of the calcium found in the treated soil
with that found in the soil from adjacent untreated plats, it was con-
cluded that calcium applied in either form at the surface of such soil
moves downward very slowly, most of it remaining for years in the
surface soil.

The analyses for calcium carbonate in the surface soils and subsoils of
Broadbalk and Hoos fields at Rothamsted, which have been made at dif-
ferent times since 1865 as reported by Hall and Miller (1905), show that
the subsoils have decreased in calcium, as well as the surface soils, which
latter had received large applications of calcium previous to 1865 and
which since that time have received yearly, for more than fifty years,
the same fertilizer treatments. The results indicate that there has been
no accumulation of calcium in the subsoils, altho there seems to be a
tendency for an increase in the subsoils where ammonium sulfate has been
applied from year to year to the surface soils.

Veitch (1904) studied the downward movement of calcium in soils by
determining the soil acidity at varied depths. The results of his investi-
gation showed that when calcium oxid was applied to soils its neutral-
izing effect was exerted only to the depth to which it was incorporated
with the soils during the various processes of preparation and _ culti-
vation.

Ames and Schollenberger (1916) present data to show the depth of soil
affected by applications of calcium salts. Soils that had been so treated
were sampled at different depths and their lime requirements determined
by the Hopkins and vacuum methods. The indications were that light
applications of lime have considerable effect on the subsoil, at least to a
depth of twenty-four inches.

White (1914) reports, from studies made on soils in the field, fh
calcium does not move horizontally to any considerable degree by diffusion,
as soil rich in calcium carbonate was found within eighteen inches of soil
distinctly acid.

+ ee OA OTT es ST

~~
<

Tue TRANSLOCATION oF CALCIUM IN A SoIL 301

- King (1904) studied the capillary movement of calcium thru soils by
filling galvanized cylinders, provided with reservoirs at their bases, with
different types of soil. A calcium solution applied at the bottom of the
soil columns was permitted to rise by capillarity thru the soils. The
results of the experiment tended to show that there was a slight upward
movement of calcium.

A comparison of the calcium content of surface and subsurface soils
as reported by Smith (1884), Snyder (1899), Ames and Gaither (1913),
Shorey, Fry, and Hazen (1917), and others, does not permit of any general
conclusion as to whether surface soils or subsurface soils contain the
greater amount of calcium. Consequently such a consideration is of no
value in a study of the translocation of calcium in soil.

A review of the literature reveals the fact that the studies thus far
made on the movement of calcium in soil have been confined almost
entirely to field experimentation and have been carried on as side experi-
ments. Results obtained under such conditions are not absolute. The
ealcium content of soils is not always constant, and in comparing one
soil with another this fact alone may lead to erroneous conclusions.

Some investigators have used a method for the determination of lime
requirement as a measure of calcium in soils. Such a practice is open
to criticism, as a lime requirement is an estimation of the absorptive
power of a soil for basic material, not a measure of its calcium content.
If calcium should liberate any of the soil bases, such a reaction might
account for any decrease found in the lime requirement of the subsoil
rather than the actual downward movement of calcium.

As previously stated, very little experimental evidence is available
concerning the movement of calcium in soil under carefully controlled
conditions. In view of this fact the experiments detailed herein were
undertaken.

EXPERIMENTAL WORK
Plan of the investigation

The investigation consisted of three experiments. These are briefly
outlined as follows:

Experiment 1.—In the first experiment the translocation of calcium
in soil was studied by leaching soil contained in pots with distilled water.
The soil was placed in the pots in three layers. In some of the pots

302 BENJAMIN DuNBAR WILSON

calcium as oxid, and in others calcium as carbonate, was incorporated
with the surface layer to test the possible downward movement of this
element; in other pots the calcium was mixed with the bottom layer of
soil to determine its tendency to move upward. The downward move-
ments of calcium oxid and calcium carbeonate, when applied to a soil in
medium, large, and excessive amounts and in equivalent quantities of
calcium, were collated. The oxid was added as burned limestone, and
the carbonate as ground limestone and precipitated calcium carbonate.”
The state of division of the ground limestone used in the experiment
was such that it passed thru a 100-mesh sieve and was held on a 200-mesh
sieve. One set of the pots was leached for six months and another set
for one year, and at the end of each period the layers of soil in each pot
were analyzed for total calcium in contemplation of determining its
movement. The experiment was set up in quadruplicate.

Experiment 2.— In the second experiment the downward movement of
calcium was determined when lots of ground limestone, differing in
fineness of division, were applied to the soil in equivalent quantities.

Pots filled with soil in three layers were treated with the ground limestone ~

in the top layer, and were leached with distilled water for one year.
Limestone of four grades of fineness was used in treating the different
pots, the treatment with each grade being repeated four times.
Experiment 3.—In the third experiment a comparative study was
made of the diffusibility of calctum in a cropped and an uncropped soil.
Pots were filled with soil arranged in layers, treated in the surface layer
with burned limestone, and leached with distilled water for five months.

Soil used

The soil used in the investigation was a Dunkirk clayey silt loam, a
glacial till soil low in organic matter. It comprises the greater part of
the soil on the farm of the Cornell University Agricultural Experiment
Station, and for this reason it was selected for study. A chemical and a
mechanical analysis of this soil, taken from the files of the Department
of Soil Technology, Cornell University, follow:

2Twice as much ground limestone as burned limestone was applied to the pots. Consequently the
quantity of calcium added to the pots treated with ground limestone was slightly in excess of that added
to the pots that received a treatment of burned limestone. As it is customary when applying calcium to
field soils to follow such a procedure, this ratio was used in experiments 1 and 2.

Onna Ay 5 aR

r

“
os

-ee aad

Tue TRANSLOCATION OF CALCIUM IN A SOIL 303

Cuemicat ANatysis (Bulk)

(An average of the analyses of nine samples)
Surface per cent

MEMCHERRINN 1 AF) 58r oP 95a Je tin Paid ds Lolo tileag . ek. 1.670
MemnOnmudioxid.........+.0.. Salemi TELE. utah) faye. Trace
SAS USGS See Te. Or ee ee ne es be | 1.740
mane es tie tar ty Der Th ly sete. euieeptal. athaliiaa 0.430
PNIRNONB ICE Sir 332). na). occisth ian val wu) MR es 1 eae 0.450
RIT Pina fesse ei bres, Sashes sees kale. GMB ealdunele’ « 1.090
TE Re tect ted ci. dha Si vid iskewend stkcd ys tah) # «aw LEO DRS d's 0.186
SI SANTI 2 be oe oe ek nea eam eeedeus tes 0.123

MecHANICAL ANALYSIS

(An average of the analyses of three samples)
Surface per cent

eer ice dak Vad eR las 0.5

EI gc ty she ta wg NN) aay area doanel a Bee Oe 0.8
IM 408 OR Se ae od eee 0.6
so ee bl wb Dee emer as Paes
RISO etre fie a ke oe y'shocie «Yi Soh ine er 9.5
eg og Nid wea ocd. Paaeth wee eee eae 67.3
Stn sg OS doe 3d AE ia ls og ea ee te 18.6

Pe re ie als. inte gaa oan Eee en te Se 100.0

A large quantity of soil was necessary to carry out the experiments,
and this was collected at three different times. For convenience, the
three soils thus obtained are designated as X, Y, and Z. Soil X was
used for experiment 1, soil Y for experiment 2, and soil Z for experiment
3. All three soils were surface soils taken from a roadside adjoining
Caldwell Field, a part of the experiment station farm. Each lot was
taken to the greenhouse, where it was screened and thoroly mixed, the
screenings being discarded. The three soils were in good physical
condition.

A representative sample was taken from each of the soils and prepared
for analysis. The lime requirement and the calcium content of each are

304 BENJAMIN DuNBAR WILSON

shown in table 1. The lime requirements were determined by the Veitch
(1904) method, and are expressed as parts per million of calcium oxid
necessary to correct the acidity in the oven-dried soils. Calcium was
determined as recommended by the Ohio Agricultural Experiment Sta-
tion (Ames and Gaither, 1913). This method was used for all the deter-
minations of calcium that were made thruout the investigation, and
consists essentially in fusing the soil with a mixture of sodium and potas-
sium carbonates, precipitating the calcium as calcium oxalate after the
removal of silicon, iron, aluminum, and manganese, and titrating the
filtered precipitate with a standard solution of potassium permanganate.

TABLE 1. Lime REQUIREMENTS AND PERCENTAGES OF CaLcruM IN Sorts X, Y, anp Z

Lime require-

Soil ment of dry soil Foe
(parts per :
million CaO) calcium
"Gh MEAN NE MOR ate ew SRT eT MIO HE La | 900 0.328
i, PRS Te tne Me ant, a ELAM LEO fi has Vici bn 800 0.300
liege, SNe SRN oA RE PMN) LR VS 1,300 0.220

Method of placing soil in pots

Glazed earthen pots 10 inches in height and 93 inches in inside diameter
were used for the experiments. In each pot was placed thirteen kilograms
of soil to form three layers. Of the eighty pots used, seventy-two were
filled in the following manner: Into the bottom of each pot was packed
five kilograms of soil, which formed the bottom, or third, layer. Over
the surface of this layer a piece of wire netting was placed, and on top
of it another five-kilogram portion of soil was packed, which constituted
the middle, or second, layer. The remaining three kilograms of soil made
up the top, or first, layer, which was separated from the middle, or second,
layer by a second piece of wire netting. The calcium oxid or calcium
carbonate with which the pots were treated was incorporated with the
soil making up the first layer before this was placed in the pots.

The remaining eight pots were filled with soil so placed that the upward
movement of calcium could be studied. In order to observe this move-

THe TRANSLOCATION OF CALCIUM IN A SOIL 305

ment, the three-kilogram portions of soil containing the calcium treat-
ments were placed in the bottom of the pots, the top and middle layers
consisting of five kilograms each. The layers were separated with wire
netting, as described above.

The soil was placed in the pots in layers in order that the calcium-
treated soil might be separated from the untreated soil, as well as for a
division of the latter, when the pots were opened. The object in dividing
the untreated soil into layers was to make possible a comparison of the
amounts of calcium in them with reference to their distance from the
calcium-treated soil.

Treatment of pots

The treatment of the pots in the three experiments may be outlined
as follows:

EXPERIMENT 1. TRANSLOCATION OF CaLciIUM Oxip AND CaALcruM CARBONATE IN SOIL

Treatment Treated
Nos. of pots (pounds per acre) layer

Re 3,000 CaO........ Top
ES fg ee Pe Soa ord go hd ase 0 ed EU ates 3,000 CaO vege Top
I iiy be eh OE Trt dg oh). ary sb. ore Zegee 91000 CaOsey 2-4 Top
Te ee oe, oe eae a win as wd we delat ws 9:000' CaO. 2. his Top
eR oe ee Pee 15,000 CaO....... Top
So ye ee icv vig og nee shoe Menlo ws 15,000 CaO....... Top
SRN ig oir. Un ees oa Sale dan eee ale ee 15,000 CaO....... Bottom
I eee a ni ee 6,000 CaCOs...... Top
ENTE Se cn ge 6,000 CaCOs...... Top
Ee AR ta 18,000 CaCOs..... Top
PELE BOM PUR. 2. 2.85 of Syhaydit eee. dh bso ets Wade Se 18,000 CaCOs..... Top
Ee Pel Sey se eaee teen ceewen 30,000 CaCOs..... Top
I oe i 2s 5 5 Ryd 5 )e 0s BIRR Sos op walt ENE ele Sle 30,000 CaCOs..... Top

A Et ae a en a ee eon 30,000 CaCOs..... Bottom

306 BENJAMIN DuNBAR WILSON

\

EXPERIMENT 2. DowNnwarp MoveEeMENT OF GROUND LIMESTONE OF DIFFERENT DEGREES
oF FINENESS THRU SOIL

Nos. of pots pore athe: Fineness of limestone
GER Ss) 5-8 Users ychar ic Meee rrice Sioa Ube 9,000 CaCOs...... Thru 10-mesh sieve, held on
52-mesh sieve
GIRO 2063 204: ery ere rene = 0:1, ee ene 9,000 CaCOs...... Thru 50-mesh sieve, held on
100-mesh sieve
GOAGOAGTA GSMs cer se eso: eee 9,000 CaCOs...... Thru 200-mesh sieve
COON Aleman oe th te cna 4 be eee 9,000 precipitated

Caters a: «:

\

EXPERIMENT 3. DowNnwarpd MovreMENT oF BURNED LIMESTONE THRU Sort CROPPED
AND UNCROPPED

Treatment
Nos, of pots (pounds per acre)
TOP ACOKOn te eve com oie era a aoa ie S000 CaOhe ee Planted (oats)
UAE SES OU cree age Micye etd en Tener Re SHOOOM CEOS am ola Unplanted

Experiments 1 and 2

The pots included in experiments 1 and 2 were leached with distilled
water equivalent to a yearly rainfall of thirty-six inches. Of these seventy-
two pots the following were leached for six months: 5, 6, 7, 8; 18, 14, 15,
16; 21, 22, 23, 24; 33, 34, 35, 36; 41, 42, 43, 44; 49, 50, 51, 52. All the
others were leached for one year. The pots leached for six months and
those leached for one year received a treatment of twenty-one and forty-
two liters of distilled water, respectively. The first treatment of water
was applied to the pots on December 22, 1915. The dates and the amounts
of the subsequent treatments are shown in table 2.

No water was applied after June 10 to the pots that were leached for
six months. These pots were allowed to drain until June 28, which was
just six months after the first drainage water had leached from them.
The soil was then prepared for the analysis of total calcium as is described
later. The pots leached for one year were sampled during the first week
in January of 1917.

THE TRANSLOCATION OF CALCIUM IN A SOIL 307

TABLE 2. Date oF TREATMENT AND AmouUNT OF DisTILLED WATER APPLIED To Pots
OF EXPERIMENTS 1 AND 2

Amount of water applied
(in cubic centimeters)

No. of treatment Date ip eA eer ea «
Pots leached | Pots leached

for six for twelve

months months

1915
WEEN WO Sots oy sacs sae vv Soe es December 22 600 600
2. Lo bce Spite se eee ene December 28 1,100 1,100
1916

“og helo 0a Galette ie January 5 1,100 1,100
tho Sug CE. CME RE OCC eR aE January 8 1,100 1,100
IRB rea). Lo. es ee eee ee January 18 800 800
Oo pees Sop Bertie 2 Bet See eee February 14 2,400 2,400
se. Mie OE ee February 21 800 800
oe Peele NaC citi ee es eee March 6 1,600 2 600
Oo ned OES ee March 20 1,600 1,600
Lb sacued eh ieet eee April 10 2,400 2,400
Lwin April 24 1,600 1,600
en RE ES Ci Is A May 6 1,600 1,600
US tee pat bil re May 8 800 800
ol aay ee tiee 6 oa May 22 1,600 1,600
ot ee cle ee May 29 800
oy a kes SOI OE eae June 10 1,100 1,100
oe daca Sele Se DE ae June: 20s Wi seats. oe 1,600
LoL ieee Sa I SS ee tiky dO Na eee Meee oes 1,600
st oo CoO UU Zia Fs i wtare estate Oe 1,600
Cl th SA en oe AUETISE Lideg dol te eee te a 2,400
ny TE Oy AO EMIGb ol) a a dwte 5 alee 1,600
ea een SRR SSE Oe Octuber o mieleencs cs -csc 2,400
Con. a he ae Ses October 10 “Fee 800
EE et de! is ered ba vied October 24 os leas aeees ae 2,400
Meer ree Ln. a aloe November: G Cee gan. os 1,600
ee A A a November: 20) |p 2.203 !.t oe 1,600
eel a) ee i a November 22} ........2. 800
I ods cine ws December Reset: ekes 1,000
a a December 10%] .c.: 355 23 1,600
Speer mre en ey A ede EN a Ba 21,000 42,000

The drainage from the pots was collected in granite-ware pans, the pots
being supported on wooden blocks (fig. 72). The water passed from the
bottom of the pots thru round openings about one-half inch in diameter.
To prevent the soil from washing thru these apertures, a small paraffined
flowerpot was inverted over them before the soil was placed in the pots.

308 BENJAMIN DunBAR WILSON

This arrangement afforded excellent drainage. In all the experiments a —
quartz-sand mulch one-half inch thick, placed on the surface of the soil,
prevented evaporation from the pots.

Bicarbonate (HCOs;) content of the drainage water

The amount of bicarbonate (HCO;) contained in the drainage water
from the pots leached for one year was determined frequently during the
investigation. Samples for analysis were collected in small Erlenmeyer a

Fia. 72, ARRANGEMENT OF POTS FOR LEACHING

flasks placed in such a manner as to catch the leachings as they came
from the pots. It was evident that the bicarbonate content of the solutions
would depend somewhat on the amount of percolation that had occurred ‘
immediately before the samples were collected for analysis, but this fact
was not objectionable as the determinations were made only that some
idea of the abundance of the bicarbonate in the leachings might be known.

It is seen from table 3 that the quantities of bicarbonate found in the
drainage water from the pots, expressed in parts per million of solution,
were sufficient to exert considerable influence on the solubility of the
calcium oxid or calcium carbonate with which the pots were treated, and

THE TRANSLOCATION OF CALCIUM IN A SOIL 309

would lead one to believe that the water applied to the surface of the soil
in the pots passed downward thru the soil, not between the soil and the
sides of the pots.

TABLE 3. Bricarsonate (HCO;) Content or DraInaGE WATER FROM Pots LEACHED
WITH DISTILLED WATER FOR ONE YEAR

(Average for similarly treated pots in parts per million of solution)

Date of collection of drainage water

‘Nos. Treatment fos)
f pot d |
hae petals per Bare) Jan. | Feb. | Mar. Apr. | June | July tae Oct. | Nov.
18 21 20 10 10 11 17 3 6

frertme lo OO CaO... .. 139 | 112 | 110 74 | 162 | 155 56 42 99
warorte 2, 9,000'CaO.. 0.0 2. oa. Poe dS 92 |- 82.| 163 | 200 74 60 125
tetor20 =| 15,000 CaO... .. 02.2... 132 | 135 | 139 | 148 | 266 | 279 | 1389 | 122 188
20 to o2..| 6,000 CaCO;.......... 144 V2), 82 OOs | Leis Pl 41 39 77
3/ to 40. .| 18,000 CaCOs......... 165°)125 88 (eg et Oh Sere 51 37 73
45 to 48. .| 30,000 CaCOs......... 141 | 130 | 113 82 | 91 82 | 55 34 60

57 to 60. .| 9,000 CaCOs, thru 10-

mesh, held on 32-mesh.| 109 92 87 61 81 69 35 28 ao
61 to 64. .| 9,000 CaCO:, thru 50-

mesh, held on _ 100-

iti ae ak Ok SSelwel. Dd) Soe oar ln voks ee oON meee 32
65 to 68. .| 9,000 CaCOs, thru 200-

TGS S ie ie ee 104 | 100 82 64 94 81 63 32 63
69 to 72. .| 9,000 precipitated

SCORES S0 Ree Pees 128} 115 91 68 92 81 44 30 39

Experiment 3

As previously stated, the object of experiment 3 was to determine the
effect of a crop on the downward movement of calcium in soil. Eight
pots were used for this purpose. The soil was placed in them in three
layers, as has been described, and each pot received a treatment of burned
limestone equivalent to an application of 3000 pounds to the acre. The
experiment was begun on February 18, 1916, when four of the pots were
planted to oats. Thirty seeds, which had been previously sterilized
with a solution of calcium hypochlorite as suggested by Wilson (1915)
were planted in each of the four pots, and the plants were thinned to
twelve in a pot on February 26. The crop was harvested on July 18,
just five months after it was planted and about the time when the grain

310 BENJAMIN DuNBAR WILSON

was ripe. There was a good stand of oats on all the planted pots at the
time when the crop was harvested.

The four unplanted pots were leached with distilled water at the same
rate as were those in the foregoing experiments, which amounted to
174 liters for five months. It was necessary to add more water to the pots
on which the plants were grown, to make up for that lost by transpiration.
During the period of growth 253 liters of distilled water was applied to
these pots. In table 4 are shown the amount of water applied to the
planted and the unplanted pots from time to time during the experiment,
and the dates of its application:

TABLE 4. Dares or TREATMENT AND AmMouNTS OF DisTILLED WaTER APPLIED To Pots
or EXPERIMENT 3

Amount of water applied
(in cubie centimeters)

No. of treatment Date
Planted Unplanted ©
pots ' pots
1916

{he ee Seen Bs Beamrecrer be fo We vate February 19 1,000 1,000
Dies. iets Cah ans SsAme org SY et a aan eae a Sie) February 26 800 800
2 Ata nor sme CPG OT, ME ioe AOI nA, RO Oe March 5 800 800
ASIAE 2 Bley reas. AI We ele Ce hig, oe eae ae March 11 1,000 1,000
GS oe tek Pn PRR Ne ea Oya on. Ae a March 24 1,000 1,000
Gee ee OM 1 ASTM Sh CAR iets ee Sinead April 10 1,600 1,600
FPN PRE IEE ARAM ce tg eo Se Fam Ome ss April 24 1,600 1,600.
baa a an nar Ale lA oon aus dads Rear ad May 4 800 | cee
ageaiteel ie 2 - REN PD SRR ee) Mery te DURE May 6 2,400 800
LOE FOS ise meres. tere era eres ae 0 May 13 800.) ..42 eee
| UAE Br) es Ser et we eM ene AERATOR ERE Wg al May 20 2,400 1,600
1D. Bh: SM RS Tee Be Ehid sow A) wie set OEE LN Rae Ee May 26 800.082. ee
1 eae a SOF d Ee ene Ss CRS am ee June 3 2,400 1,600
1 tes GOR a Li a a orc aE eet dn unten dy ne VE June 14 8000) on 3h. ae
LS hey 2h Eee GRR: SEE rath: Le ad ie BAA Ae ate June 17 2,400 1,600
1G. chs Ae Ee PEE ee oo Pe st See Be June 27 2,400 1,600
1A Neste a aac a a Tt St RE eS Tie ee July 8 2,500 2,500
SO GAUL res re is iece eh echt ca ER eee | See ee 25,500 17,500

Method of sampling pots for analysis of calcium

When the last application of water had drained from the pots, the
quartz-sand mulch was removed from the surface of the soil and the pots

hee

—

THE TRANSLOCATION OF CALCIUM IN A SOIL onl

were allowed to stand for several days in this condition until the soil was
dry enough to be in a good workable condition. A large spatula was
used to loosen the soil from the sides of the pots, and by this means it
was possible, when inverting the pots, to slide the soil from them as a
solid cylindrical mass (fig. 73). In order to guard against the possibility
that calcium salts might have been carried down mechanically, during
the course of the experiments, between the soil and the sides of the pots,
the outside soil ofthe entire soil mass was removed with a knife, leaving
what might be called an inner core of soil. This inner soil core was

Fic. 73. CORES OF SOIL AS THEY CAME FROM THE POTS, BEFORE AND AFTER DIVISION

divided into three layers by inserting a spatula where the pieces of wire
netting had been placed in the soil at the time when the pots were filled
(fig. 74). The three layers thus obtained were placed in different
receptacles, and a representative sample taken from each of them was
air-dried. A portion of this air-dried sample was passed thru a 32-mesh
sieve, oven-dried over night, and finally placed in an air-tight eight-ounce
bottle, which was set aside until the soil could be analyzed for totai
calcium according to the method already described (page 304).

None of the soil layers into which some form of calcium had been
placed were analyzed for this constituent at the end of the experiments,

374 BENJAMIN DuNBAR WILSON

Fig. 74. LEFT: THE BOTTOM OF A CORE OF SOIL.
RIGHT: A CORE OF SOIL DIVIDED INTO ITS THREE LAYERS, SHOWING WIRE
NETTING USED

but the amount of calcium present in them at the beginning of the experi-
ments is given in tables 5 to 9. The percentages of calcium found in
the analyzed layers at the end of the experiments are taken as an indi-
cation of the translocation of this element thru the soil, and are also given
in the tables.

TABLE 5. Exprriment 1 — PERCENTAGES oF CALCIUM IN SECOND AND THIRD LAYERS

oF Sow FRoM Pots LEACHED wiTH DISTILLED WATER FoR Stx MontTus

(Calcium treatments placed in first layer of soil)

Per cent of calcium in soil layers
|
ALG Ree Begin- Treat-
reatmen O. ning of End of . ; ment
(pounds of experi- experiment Arithmetic micar desig-
per acre) pot ment nation
First Second | Third Second Third
layer Inver | layer layer layer
t
5 | 37 41
6 40 38
3,000 CaO... 7 0.69 33 39 .370+ .0098 .3890+ .0049 A
8 | 38 38
| 33 34 28
: 34 = 84 28
6,000 CaCOs. 35 0.73 “97 "99 315+ .0122 . 295+ .0085 A
| 36 ol 29

G

Tue TRANSLOCATION OF CALCIUM IN A SOIL

TABLE 5 (concluded)

Per cent of calcium in soil layers

Begin-
Treatment | No. ae of End of
(pounds of experi- experiment Arithmetic mean
per acre) pot ment
First Second | Third Second Third
layer layer | layer layer layer
13 30 By
14 ol 232
9,000 CaO... 15 1.41 "39 33 .355+ .0122 . 330+ .0049
16 35 235
( 41 33 33
42 .29 “SLA
18,000 CaCOs 43 1.54 "39 "33 .315+ .0061 .3825+ .0036
44 32 .33
: 21 37 37
22 38 37
15,000 CaO.. 23 2:12 39 37 .3885+ .0049 .365+ .0036
24 40 35
49 .30 31
50 135 35
30,000 CaCOs 5] 2.33 39 "39 .310+ .0073 340+ .0122
52 32 38

313

Treat-
ment

desig-

nation

Bi

C

314

TABLE 6. ExprrimMent 1 — PERCENTAGES OF CALCIUM IN SECOND AND THIRD LAYERS

BENJAMIN DuNBAR WILSON

or Som From Pots LEacHED WITH DisTILLED WATER FOR ONE YEAR

(Calcium treatments placed in first layer of soil)

Per cent of calcium in soil layers

Treatment | N rae
reatmen oO. ; f End of . :
(pounds of seals ee ariceut Arithmetic mean
per acre) pot ment
First Second | Third Second Third
layer layer | layer layer layer
i) a3) -O2
2 34 36
3,000 CaO... 3 0.69 37 38 .340+ .0098 345+ .0122
4 .30 32
29 32 25 |
30 32 .30
6,000 CaCOs. 3] 0.73 36 “99 303+ .0103 . 293+ .0109
32 ol 33
9 .30 29
10 33 31
9,000 CaO...) 4 34 / 1.41 30 93 .305+ .0061 .303+ .0085
2 .29 28
37 33 39
38 33 30
18,000 CaCO; 39 1.54 "39 "39 3820+ .0049 .310+ .0122
40 .30 27
17 34 39
18 : .32 30
15,000 CaO. .|) 46 De, 30 34 .825+ .0073 340+ .0122
20 34 oo
45 .3l stl
46 .29 27
30,000 CaCOs) ¢ 47 2.33 30 ‘O7 . 293+ .0061 .273+ .0019
48 21 .28

Treat-
ment

desig-

nation

Di

Ky

Fy

Tue TRANSLOCATION OF CALCIUM IN A SOIL 315

TABLE 7. Exprertment 1 — Percentaces or Catcium In First AND SECOND LAYERS
OF Sort FRoM Pots LEACHED witH DisTILLED WATER FOR ONE YEAR

(Calcium treatments placed in third layer of soil)

Per cent of calcium in soil layers

, Begin- , Treat-
Treatment | No. ning of End of Arithmeti ment
(pounds of experi- experiment a desig-
per acre) pot ment atin
} Third First | Second First Second
: layer layer | layer layer layer
25 ooo, 30
26 By? 538°
15,000 CaO.. 97 i We 34 35 .318+ .0066 .315+ .0122 G
28 .29 28
53 .29 130
54 .29 BP,
30,000 CaCO: 55 2.33 31 28 .300+ .0049 .313+ .0109 Gi
56 Jo 30
4
TABLE 8. Experiment 2 — PERCENTAGES OF CALCIUM IN SECOND AND THIRD LAYERS
_ oF Sort From Pots LeEacHEeD witH DisTILLED WATER FOR ONE YEAR
Calcium treatments placed in first layer of soil)
; p
" a —
Per cent of calcium in soil layers
aM seater gg Nox uf aad rane Mee
oun fo) r ning o Ind o F . :
, ae acre) limestone pot | experi- experiment Arithmetic mean prea
} ment
First Second | Third Second Third
layer layer layer layer layer
Thru 10-mesh, 44 Se ‘Be |
9,000 CaCOsz held on 32- 59 0.91 39 35 f .328+.0085 ) .328 +.0061 H
mesh 60 "33 31 J
Thru 50-mesh, He A }
9,000 CaCO» | held on 100-'}| 62 }| 0.91 ae 33 285 +.0049 | .265 +.0049] I
mesh 64 27| 26
65 29 28) |
9,000 CaCOs | Thru 200-mesh | 0.91 32] 37} | .208-+.0085} 295 +.0061] J
68 31 .29
69 ees .29 }
9,000 CaCOs | Precipitated || 4°}| 0.91 28) -28\) 310.0146] .298 +.0081] K
CaCOs 72 98 | 29

So ee ee eee ee ee ee

316 BENJAMIN DuNBAR WILSON

TABLE 9. ExprerRIMent 3 — PERCENTAGES OF CALCIUM IN SECOND AND THIRD LAYERS
oF Croppep AND UNcroprrep Sort From Pots LEACHED wiITH DisTILLED WATER FOR
Five Monrus

(Calcium treatments placed in first layer of soil)

Per cent of calcium in soil layers

; Treat-
Treatment Planted N Begin- eee
(pounds or © ning of End of ; : pe
per acre) unplanted pot | experi- experiment Arithmetic mean rey
ment
First Second | Third Second Third
layer layer layer layer layer
73 21 .18
3,000 CaO | Planted (oats) |} 75} | 0.58 70] 6-33) | 210.0073] .218 +.0090] L
76 .24 222,
( vie .18 wae,
3,000 CaO | Unplanted 73 il 0.88 32 | -33)) 195+.0073 | .205 +.0098] In
80 18 .18

INTERPRETATION OF ANALYTICAL DATA

The amounts of calcium present in the analyzed layers of soil at the
end of the experiments, from the pots that had received the same calcium
treatment, varied to some extent, as is seen from tables 5 to 9. The
variation in the calcium content of the soil from pots similarly treated
appears to be about as great as that shown by a comparison of differently
treated pots. In view of this fact, it became necessary to determine
the experimental error of the investigation, before any definite conclusions
could be drawn regarding the movement of calcium thru the soil, in
relation to the following points: (1) Did the analyzed soil layers contain
more calcium at the end of the experiments than was contained in the
original soils at the beginning of the investigation? (2) Did the layer
of soil adjoining the one treated with calcium contain more of this element
than the layer farther removed? (3) If calcium had moved thru the soil,
did the degree of movement vary with smaller or larger applications of
this constituent? In order to draw conclusions accurately from the data
presented, the arithmetical mean value with its probable error, for the
amount of calcium present in the soil layers resulting from different
calcium treatments, was determined. These values are given in the
tables and are used in interpreting the results of the investigation. For

Se ee

ee a

THE TRANSLOCATION OF CALCIUM IN A SOIL ol?

convenience the letters in the extreme right-hand column of each table
are used to designate the different pot treatments.

Peter’s formula as given by Mellor (1909) was used in determining
the probable errors. According to this formula, the probable error, R,
of the arithmetical mean of a series of observations is

R= + 0.8453 oben v)

n Nn-1

in which ¥ (+ v) denotes the sum of the deviations of every observation
from the mean, their sign being disregarded, and n denotes the number
of observations actually made. The increase of calcium in one layer of
soil over that in another layer, in pots similarly or dissimilarly treated,
or the amount of calcium present in the soil from a calcium-treated pot
over that in the original soil at the beginning of the experiment, can be
determined by subtracting the arithmetical mean value of calcium for any
one particular soil from that for any other soil, the probable error of the
difference being derived from the formula

B=VE, TE,
in which E; is the probable error of one mean, and E; the probable error
of the other. This procedure is followed in explaining the results of the
experiments shown in tables 5 to 9.

A comparison of the amounts of calcium found by analysis in the

analyzed soil layers from pots that were similarly treated is given in

table 10, which was compiled from the data given in tables 5 to 9 inclusive.
This table shows that in eleven cases out of twenty there was a greater
amount of calcium in the layer of soil adjoining the one that had been
treated with calcium, that in eight of the cases the soil layer farther
removed from the treated layer contained the greater percentage of
calcium, and that in one case there was an equal amount of calcium in
each of the untreated soil layers. The differences in the amounts of
calcium in the two soil layers are not great enough to be of any conse-
quence, however. Wood and Stratton (1910) have shown that in order
to be significant, differences resulting from different treatments should
be at least 3.8 times their probable error, corresponding to odds of 30 to

-1 that such differences are real and not due to normal variation. As none

of the differences appearing in table 10 are significant, it is safe to con-

318 BENJAMIN DuNBAR WILSON

clude that the soil layers which were analyzed did not differ in their
calcium content for any one particular treatment. This being true, the
remainder of the discussion of the results may be confined to a con-
sideration of the soil layer adjacent to the layer receiving the calcium
treatment. In every case, regardless of the position of the calcium-treated
layers in the pots, this is the second layer of soil.

TABLE 10. Comparison oF THE AMOUNTS OF CALCIUM IN THE ANALYZED LAYERS OF .
Sort FRoM Pots SIMILARLY TREATED

(For the differences to be significant, the mean must be 3.8 times the probable error)

Layer
Difference having Duration of | No. of
Treatment in amounts the greater eben at experi-
of calcium amount of ment
calcium
In second and
third layers
J Ne at Sieg 7a i MR hg 3 oe SR .020 + .0109 | Third
VeANeAp pi te car at 0 TYG ge ah .020 + .0147 | Second Sia aionbhe
Bs are eng etn 38% 025 + .0131 | Second seca
Bares Red We ee i .010 + .0071 | Third
(CAM ee Adit RS. SMe eR .020 + .0061 | Second
Oi Ore wee See ae he Lb ea tonge .030 + .0142 | Third
1D Me Vis © 1s Wits 5 ea .005 +.0156 | Third
et i he as eee aee gy 010 +.0149 | Second 1
VEE WA oa is Cee eR ae ES .002 +.0104 | Second
ME ead eld Piha REA EN En Rae MRE .010 +.0131 | Second
He ON Eee eect he Ll Bees we he .015 +.0142 | Third
eS On icc HT eS ae .020 + .0064 | Second Twelve months
In first and
second layers
ee ier fay Dats BO Sale aa a .003 + .0138 | First
GM araiel ir os be imgee SARA AY Gi kat gS Meta .013 +.0119 | Second
In second and
third layers
ER ei. ees) Ree Ske SRE .000 + .0104
ee eee teeta. fe, 020 £.0069 | Second Twelve imontid
J POA reat, DREN Ae <0 E .003 +.0104 | Second
her ead bg UN IE NP ite Ct a @ 4: .012 +.0167 | Second
re RE Re oe en ey .008 +.0116 | Third -
| On ae) ek i 010 + .0122 | Third Bive montis

;

THE TRANSLOCATION OF CALCIUM IN A SOIL 319

Results of experiment 1

The differences in the percentage of calcium in the second layer of
soil, resulting from different calcium treatments, are shown in table 11. It
is evident from this table that in the one case when the mean is greater
than 3.8 times the probable error, the soil from the pots receiving treat-

TABLE 11. Comparison or tHe AMouNTS oF CALCIUM IN THE SECOND LAYER oF SoIL
FROM Pots DIFFERENTLY TREATED IN EXPERIMENT 1

(For the differences to be significant, the mean must be 3.8 times the probable error)

Difference in Treat- Layer of
amounts of ee Duration of soil in Calci
Treatments calcium in showing experi- which Pee ae
compared ay greater i :
second layer | . ount of ment calcium compared
of soil eaten was placed
PAtamG Ager. cs. ss .055 + .0156 A
eand, Bi... 5... .040 + .0137 B Six months fate aR Wisk!
Meand Ore.... 2.5: .075 + .0088 C Bae op
EE eee First ne
WDeand Wy... . .037 + .0142 1D)
| ae mats 0078'S R,<) |, PPP. CaCO:
iad Py... 6... 032 + .0095 F sere F
A and B .015 +.0156 A
A Su a 015 +.0109 C Six months
2 Cn .030 + .0131 Cc Different
ee ee 3 First ee of
nit 0) f .0115 ‘a
| ae 015 +.0122 | D pie ake
oe ne .020 + .0095 F eR
(Cael Cae .002 + .0163 G Equivalent
Twelve : quantities of
months Third CaO and
CaCOs

ment C contained more calcium in the second layer than did the soil

from the pots receiving treatment C;. C being greater than C,, and the
difference between A and A, being almost without the experimental
error, it appears that the second layer of soil from the pots that were
leached for six months contained more calcium when the first layer had
been treated with burned limestone than when the first layer had received
a, treatment of ground limestone. When the soil with similar treatments

329 BENJAMIN DuNnBAR WILSON

was leached for twelve months, this relationship between the burned and
the ground limestone treatments is not shown, as can be seen from the
table. It seems reasonable to believe that the results from the soil that
was leached for the longer period are nearer the truth, as this soil had a
longer time in which to become adjusted to the conditions of the experi-
ment. If this assumption is true, it can be concluded from the results
given in table 11 that the burned limestone did not move downward in
the soil more rapidly than did the ground limestone. The table also
reveals the fact that there was no more calcium present in the second
layer of soil resulting from larger applications of burned limestone than
there was from smaller applications of this substance, and that there
was no appreciable difference between the amounts of calcium present
in the second layer of soil from the pots that had been treated with either
burned limestone or ground limestone in the third layer.

The question now arising is whether or not the amounts of calcium
present in the second layer of soil from the pots in experiment 1 which
were treated with burned limestone (since the tendency was for the pots
treated with burned limestone to contain more calcium in the second
soil layer than those treated with ground limestone) are large enough,
when compared with the amount of calcium in the soil at the beginning

TABLE 12. Comparison oF THE AMOUNTS OF CALCIUM FOUND IN THE SECOND LAYER OF
Sort aT THE END oF EXPERIMENT 1, WITH THE AMOUNT PRESENT IN THE SOIL AT THE
BEGINNING OF THE EXPERIMENT

(For the differences to be significant, the mean must be 3.8 times the probable error)

Calcium Calcium
present in present in
Treatment second layer soil at Difference Duration of
of soil beginning of in calcium experiment
at end of experiment
experiment
1 rea BETA AE Po .3870 +.0098 ° .042 + .0184
Bhs LER e RS eet .305 + .0122 .328 + .0156 .027 +.0198 | Six months
Gk Site, cee ee .3885 + .0049 | .057 + .0164
1D a ea srt a eta TR Li .340 + .0098 .012 + .0184
Bias Soke eee ee .305 + .0061 : .023 + .0168
Foo) os sss sc se ese, } B25 0073 (| 828-0156 1) “onc oazo | 2 =i a
Ge ee A IMSS 2 n000G3) _ .010 + .0169

Tue TRANSLOCATION OF CALCIUM IN A SorL 321

of the experiment, to show that there was an upward or a downward
movement of this constituent during the course of the experiment. Such
a comparison is made in table 12. Treatment C shows a downward,
movement of calcium into the second soil layer that is almost within
certainty; but since treatments A, B, D, E, and F do not indicate such a
movement, it can be concluded that there has been no downward move-
ment of calcium within the soil. No upward movement of calcium
resulted from treatment G, as can be seen from the table.

Results of experiments 2 and 3

The. results of experiments 2 and 3 are interpreted in the same way
as are those of experiment 1, and are summarized in tables 13 and 14:

TABLE 13. Comparison oF THE AMOUNTS OF CALCIUM FouND IN THE SECOND LAYER
oF Sor, AT THE END OF EXPERIMENT 2, WITH THE AMOUNT PRESENT IN THE SOIL AT THE
BEGINNING OF THE EXPERIMENT

(Limestone added in equal amounts. For the differences to be significant, the mean must
be 3.8 times the probable error)

Calcium Calcium ae
resent in , = cs of soi
Treat- aid layer sig Difference es a in which Fineness of lime-
ment of = beginning of in calcium .- experi- calcium stone applied
at end of experiment ment ayes
experiment placed
H .328 +.0085 .028 +.0176 H—Thru 10-mesh
sieve, ae on 32-
: mes
I .285 +.0049 .015 +.0162 I—Thru 50-mesh
300 + .0154 eyene Hirst sieve, held A 100-
os Sars months mes
J .298 +.0085 .002 +.0176 J—Thru 200-mesh
sieve
i .310 +.0146 .010 +.0212 K—Precipitated
CaCOs

There was no movement of calcium from the first to the second layer
of soil in the pots that were treated with ground limestone at the rate
of 9000 pounds to the acre, regardless of the fineness to which the lime-
stone had been ground, nor with an equivalent quantity of precipitated
calcium carbonate. This fact is well brought out by the figures in table 13.
The differences shown in the table between the amount of calcium in
the soil at the beginning of the experiment and that found in the second
soil layer at the end of the experiment are not great enough to indicate
any movement of this element.

ee BENJAMIN DuNBAR WILSON

In table 14 it is shown clearly that growing oats on the potted soil
treated with burned limestone at the rate of 3000 pounds to the acre had
no influence on the downward movement of calcium thru the soil. There
was no movement of calcium in the soil either with or without the growth

TABLE 14. Comparison oF THE AMOUNTS OF CALCIUM IN THE SECOND LAYER OF SoIL
FROM PLANTED AND UNPLANTED Pots IN EXPERIMENT 3

(Calcium added in equal amounts as burned limestone. For the differences to be significant,
the mean must be 3.8 times the probable error)

Difference Treatment Layer of
in amounts showing Duration soil in
Treatments compared of calcium in greater of which
second layer amount of | experiment calcium
of soil calcium was placed
iin Miia eee eee oes .015 + .0103 L Five months First
1p era Ait g BR tie CR a te Mi a AB .010 + .0088 Z

* Z (original soil) = .220 + .0049

of plants, as is shown by a comparison of the calcium present in the second
soil layer at the end of the experiment with that present in 7 soil at
the time when the experiment was begun.

SUMMARY

Calcium applied to a clayey silt loam soil in the form of burned lime-
stone, ground limestone, or precipitated calcium carbonate, did not
move downward in the soil to any appreciable extent when the soil was
leached in pots for one year with distilled water.

The soil from some of the pots that were leached for six months showed
a slight movement of calcium when the soil had been treated with burned
limestone, while the soil from the pots leached for twelve months with
similar treatments did not show such a movement. This inconsistency
cannot be explained unless there was a mechanical movement of calcium
in the soil from certain of the pots that were leached for six months.
As hereinbefore stated, the results obtained from the soil leached for
the longer period are given preference over the others, and this permits

THE TRANSLOCATION OF CALCIUM IN A SoIL 323

the conclusion that neither small nor large applications of burned or
ground limestone resulted in a downward movement of calcium.

Calcium incorporated with the soil as burned or ground limestone
and placed in the bottom of the pots did not move by diffusion into the
upper soil layers.

No. movement of ground limestone thru the soil was evident when
applied at the rate of 9000 pounds to the acre, irrespective of the fineness
to which the rock had been ground. There was no difference in the
movement of limestone ground to pass a 200-mesh sieve and that veld
on a 32-mesh sieve.

Precipitated calcium carbonate when applied to the soil in large amounts
did not move downward to the untreated adjacent soil.

Oats grown in pots on the soil that had been treated with burned lime-
stone had no effect in bringing about a descent of calcium.

It seems logical to believe that a soil deficient in calcium will absorb
this constituent from the drainage water as it percolates thru the soil.
No doubt this occurs, but the amount held by the soil is evidently so
small that it cannot be detected by a chemical analysis. Conclusions
drawn from small differences of calcium found in soil upon analysis are
hardly trustworthy, as it is often difficult to obtain concordant results
from the same sample of soil. When small differences are calculated
to pounds of calcium in an acre foot of soil, as is often done, the real
value of such results is questionable.

CONCLUSION

The results of this investigation are summarized briefly in the following
statement: 4

The translocation of calcium thru a clayey silt loam soil with a rather
large lime requirement is extremely slow, since in these experiments no
upward nor downward movement of this element was perceptible twelve
months after small, large, or excessive amounts of calcium salts were
applied to the soil.

ACKNOWLEDGMENT

The writer desires to acknowledge his indebtedness to Professor T.
Lyttleton Lyon, under whose direction this work was done.

324 BENJAMIN DUNBAR WILSON

LITERATURE CITED

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BroucutTon, L. B.. How lime is distributed through and lost from soils.
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Kine, F. H. Investigations in soil management, p. 1-168. (Reference
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Metior, J. W. Higher mathematics for students of chemistry and
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Wuits, J. W. The results of long continued use of ammonium sulphate

upon a residual limestone soil of the Hagerstown series. Pennsylvania
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Witson, James K. Calcium hypochlorite as a seed sterilizer. Amer.
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Memoir 15, Insects Injurious to the Hop in New York, the second preceding number in this series of
publications, was mailed on November 19, 1918

be if!
H aie

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