TEXAS AGRICULTURAL EXPERIMENT STATION

a DECEMBER, 191s

BULLETIN NO. 183

DIVISION OF CHEMISTRY

Moisture Relations of Some
Texas Soils

   
   

    

  
 
  
   

  
      
  

  
  

   

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POSTOFFICE
COLLEGE STATION, BRAZOS COUNTY, TEXAS

E
AUSTIN. TEXAS
Von BOECKMANN-IJQgIgES Co., PRINTERS

[Blank Page in Original Bulletin]

A]7l-12l5-10m

TEXAS AGRICULTURAL EXPERIMENT STATION

BULLETIN NO. 183 DECEMBER, 1915

DIVISION OF CHEMISTRY

Moisture Relations of Some
Texas Soils

BY

G.’ S. FRAPS, Ph. D.
Chemist in Charge; State Chemist

 

POSTOFFICE
COLLEGE snmow, BRAZOS COUNTY, TEXAS

AUSTIN, TEXAS
VON BOECKMANN-JONES co., PRINTERS
1915

AGRICULTURAL AND MECHANICAL COLLEGE OF TEXAS

W. B. BIzzELL, A. M., D. C. L., President

TEXAS AGRICULTURAL EXPERIMENT STATION
BOARD OF DIRECTORS

L:
O
I

N I". GUION, President, Ballinger
. HART, Vice President, San Antonio

i111“
ESQ

F.

z~se~

E.
. C. BREIHAN, Bartlett
A

>

B DAVIDSON, Cuero .................................. .,

 
 
  
  
 

. AsTiN, Bryan......................................‘.'..I.'.:::SCSI.
. S WILLIAMS, Paris .................................................. ..
BATTLE, Marlin ................................................. ..
KUBENA, Fayettevilleiiiiiiiiiiiilii:i““i:jiiiii:i:i:H:imiliiiiiiiijiiij.
. MILLER, JR., Amarillo .................................................... ..

................................................... .. Term expires 1919

........................... ..Term expires 1919
.......................... .. Term expires 1919
Term expires 1917
.............................................. ..Term expires 1917

.............................. ..Term expires 1917
.............................. ..Term expires 1921
.............................. ..Term expires 1921

  

.................................................. ..Term expires 1921

MAIN STATION COMMITTEE

L. J. HART, Chairman

J. S. WxLLIAMs

\V. A. MiLLER, JR.

GOVERNING BOARD, STATE SUBSTATIONS

P. L. DOWNS, President, Temple ........ ..
CRARLEs ROGAN, Vice President, Aust
W. P. HOBBY, Beaumont ...... ..
J. E. BOOG-SCOTT, Coleman

  
  

..................................................... ..Term expires 1919

.............................................. ..Term expires 1917

.................................................... ..Term expires 1917

Term expires 1921

*STATION STAFF

ADMINISTRATION
B. YOUNGBLOOD, M. S., Director
A. B. CONNER, B. S Vice Director
CHAS. A. FELKER, Chief Clerk
A. S. WARE, Secretary

DIVISION OF VETERINARY SCIENCE
M. FRANCIS, D. V. S., Veterinarian in
H. SIIJIITSIIDT, D. V. M., Veterinarian

DIVISION OF CHEMISTRY
G. S. FRAPs, Ph. D., Chemist in Charge;
State Chemist _ _
R. H. RinaELL, B. S., Assistant Chemist
FRANK HODGES, B. S., Assistant Chemist
W. T. P. SPROTT, B. S., Assistant Chemist

DIVISION OF HORTICULTURE _
H. NEss, M. S., Horticulturist in Charge
W. S. HOTCHKXSS, Horticulturist

DIVISION OF ANIMAL HUSBANDRY

J. C. BURNs, B. S.._ Animal Husbandman
Feeding Investigations '

J. M. JONEs, A. M., Animal Husbandman
Breeding Investigations

DIVISION OF ENTOMOLOGY
F. B. PADoOcR. B. S., Entomologist in
Charge; State Entomologist.
O. K. COURTNEY, B. S., Ass stant Entomol-
ogist
DIVISION OF AGRONOMY
A. B. CONNER, B. S., Agronomist ii-i Charge
A. H. LEIDIGH, B. S., Agronomist
Louis WVERMELSKIRCHEN, B. S.,Agron0mist
DIVISION OF PLANT PATHOLOGY AND
PHYSIOLOGY
F. H. BLODGETT, Ph. D., Plant Pathologist
and Physiologist in Charge
N. D. ZUBER, B. S., Fellow
**DIVISION OF FARM MANAGEMENT

REX E. WILLARD, M. S., Farm Management
Expert in Charge.

DIVISION OF POULTRY HUSBANDRY
B. N. HARVEY, B. S., Poultrgman in Charge

SUBSTATION NO. 8:

DIVISION OF FORESTRY

J. H. FOSTER, M. F., Forester in Charge;
State Forester

DIVISION OF FEED CONTROL SERVICE
JAMES SULLn AN, Executive Secretary
CiiAs. A. FELKER, Chief Clerk
J. H. ROGERS, Inspector

WOOD, Inspector

. H. WoLTERs, Inspector

. D. PEARcE, Inspector

. M. WICKES, Inspector

T. B. REESE, Inspector

SUBSTATION NO. 1: Beeville, Bee County
E. E. BINFORD, B. S., Superintendent

SUBSTATION NO. 2: Troup, Smith County
W. S. HOTCHKISS, Superintendent

SUBSTATION NO. 3:
C0

€"’*'3_€

Angleton, Brazoria

unty

N. E. WINTERS, B. S., Superintendent

SUBSTATION NO. 4:
Coun

H. H. LAUDE, B. S., Superintendent
SUBSTATION NO. 5: Temple, Bell County

A. K. SHORT, B. S., Superintendent
SUBSTATION NO. 6:

County

V. L. CORY, B. S., Superintendent
SUBSTATION NO. 7: Spur, Dickens County

R. E. DICKSON, B. S., Superintendent
Lubbock, Lubbock

Beaumont, Jefferson

Danton, Denton

County _
R. E. KARPER, B. S., Superintendent
SUBSTATION NO. 9: Pecos, Reeves County
J. W. JAcKsON, B. S., Superintendent
SUBSTATION NO. 10: (Feeding and Breed-
ing Substation) College Station, Brazos
County _
T. M. REnnELL, Superintendent
SUBSTATION NO. 11: Nacogdoehes, Nacog-
doches County
G. T. McNEss, Su erintendent _
D. T. KrLLOucR, . S., Scientific Assistant
"SUBSTATION NO. 12, Chillicothe, Harde-
man County _
R. W. EowARos, B. S., Superintendent

CLERICAL ASSISTANTS

J. M. SCHAEDEL, Stenographer
DAISY LEE, Registration Clerk

. F. CHRISTIAN, Stenographer
ELIZABETH WALKER, Stenographer
M. P. HOLLEMAN, JR., Stenographer.

*As of December 1, 1915.

J. L. COTTINGHAM, Stenographer
E. E. KILBURN, Stenographer
C. L. DURST, Mailing Clerk
WILLIE Joiiusou, Tag Clerk

**In Cooperation with the United States Department of Agriculture.

 

CONTENTS.
_ PAGE.
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Plan of Experiment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Description of Soils . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Curves Showing Relations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 11

Maximum Water Content of Soils . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

The Effect of Cultivation on Water Held . . . . . . . . . . . . . . . . . . . . . . . 19

Water at the Ends of the Dry Periods. . _, . . . . . . . . . . . . . . . . . . . . . . . 21

Effect of 'I,‘reatment" Upon Water Content . . . . . . .  . . . . . . . . . . . .. 25

Losses of Moisture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 31

Water Content of the Soil Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 35

Acknowledgnqgnts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 35

Summary and Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 35

[Blank Page in Original Bulletin]

MOISTURE RELATIONS OF SOME TEXAS SOILS

BY G; S. lhmrs, Ph. D., CHEMIST IN CLIARGE; STATE OHEMIsT.

Soil moisture is an exceedingly important controlling condition for
Texas crops. There are times when the rainfall is excessive and the
crops suffer from too much moisture, and in limited sections of the
State this condition occurs often. In most sections, the crops suifer
more often from too little moisture, and the yield is cut short on account
of deficiency of Water. This is particularly the case With corn; a. dry
period at the time of tasseling, in one sect-ion of the State or another,
cuts short the production of grain almost yearly. Corn is a shallow
rooting crop and suffers more frequently from lack of moisture. than
cotton. Cotton sends down a deep tap root, and can Withstand dry
Weather, as it takes moisture from the depths of the soil.

Soil moisture is, to a certain extent, susceptible to control. Fall plow-
ing, in some soils, opens them up and allows the Water and air to pene-
trate and be absorbed by the soil. Shallow cultivation decre-ases the
loss of moisture by evaporation. Cultivation at the right time has often
increased the corn crop, or saved a crop that would have been lost by
drouth. Vegetable matter makes the soil more porous, more easily
penetrated by Water, and more retentive of moisture and allows the roots
to touch more easily the moisture-laden soil particles. Lime is needed
on some heavy clay soils, to alloW Water to penetrate more easily and
to allow air to enter and the roots to penetrate. Drainage opens chan-
nels for air and roots, drains off the surplus moisture, a.nd by allowing

the roots to go deep-er into the soil, permits the utilization of much .

larger stores of soil moisture.

All these methods, properly applied according to the needs of the
particular soil under cultivation, assist in holding soil moisture, or
bringing the roots into possession of that already there. Deep pene--
tration of plant roots is an important requisite for goo-d crops in sec~
tions liable to suffer from dry Weather.

In Bulletin No. 1'71 of this station We reported studies of soil moisture
conditions in 'l"exas soils, as ascertained bv percolation experiments, in
which the quantities of Water Which percolated through pots of the
soils Were measured. This method of experiment does not show the
quantities of Water contained in the soil at various intervals. The per-
colation is affected, to a considerable extent; by the relative moistnes-s
of the soil. The experiments reported in the present bulletin Were
designed to supplement the other Work. by showing the condition of
moisture of the soils at various intervals.

PLA N OF EXPERIMEN T.

The soil, dry and pulverized, was placed in cans six inches in diam-

p eter, on top of a layer of gravel which filled the funnel in the bottom

TEXAS AGRICULTURAL EXPERHIEZ\"T STATIOY.

4 P
..F_[ H,

F19. Fi

MorsrURE RELATIONS OF SoME TEXAS SorLs. 7

of the can. The cans Were Weighed, saturated with distille-d water,
again Weighed, and placed out in an outer casing, which had been pre-
viously imbedded in the soil, so as t0 project about one inch above it.
Figure A gives the dimensions of the can, the outer casing, and the
bucket for collecting the percolating Water. As some of the soils
expanded on wetting, the soil later o-n Was removed to a depth of two
inches from the top of the can, dried, Weighed, and the Weight deducted
from the original soil. Additions and cultivations were then ma.de to
the pots according to the plan given in Table 1.

‘TEXAS’ AGRICULTURAL EXPERIMENT STATION.

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JCOEQMOMQ; .02  .02 w0n~ ¢cos5mofir .02  .02 Dflmw

dfiom H0 FZHEH<HMBIIJ HHQFH

Morsruam RELATIONS 0F SOME TEXAsSOILs. 9

The period of observation began May 1, 1911, and ended January 1,
1913, covering nearly two years. A large number of Weighings and
observations were made during this period, but it is unnecessary for the
purpose of this discussion, to record the entire mass of data. Curves
are presented elsewhere in the bulletin, for certain of the soils, which
record the data in detail. -

The weighings were, at times, afiected by the wind, as they were
made out of doors. Due ‘allowance has been made for this wherever
necessary and so far as possible. _

The rainfall], by days, for the period of observation is given in Table 2.

TABLE 2.—RAINFALL IN INCHES, 1911.

Days ofMonth. June July Aug. Sept. Oct_ Nov. Dec,

   

10 TEXAS AGRICULTURAL EXPERIMENT STATION.

TABLE 2 RAINFALL IN INCHES, l9l2—v-Continued.

Days of Month. Jan. Feb. Mar. Apr. May June July Aug. Sept. Oct. Nov. Dec.
1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 10..... .37 . . . . . . . . .. 15 . . . . . . . . .. Tr

2 . . . . . . . . . . . . . . . . . . . . . . . .. .02  .47 .27 19 . . . . . . . . . . . . . . . . . . .. 02

3 . . . . . . . . . . . . . . . . . . . . . . . .. .02..... Tr. .03..... 02 09 . . . . . . . . .. 129

4 . . . . . . . . . . . . . . . . . . . . . . . .. .01  .89 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 30

5 . . . . . . . . . . . . . . . . . . . . . . . .. 1.60..... .01 34 . . . . . . . . . . . . . . . . . . . . . . . .. 10

6 . . . . . . . . . . . . . .. 04 . . . . . . . . .. Tr .42 08..... 01 . . . . . . . . . . . . . ..

7 . . . . . . . . . . . . . .. 01 .02 1.49 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..

8 . . . . . . . . . . . . . .. 02..... .05 .10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 04

9 . . . . . . . . . . . . . . . . . . . . . . . .. Tr. .15 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 09

1O . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. .03 .06 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 24

11 . . . . . . . . . . . . . .. .61  .23 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 101

12 . . . . . . . . . . . . . .. .05 . . . . . . . . .. 10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 35

13 . . . . . . . . . . . . . . . . . . .. 1.07 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. O1

14 . . . . . . . . . . . . . . . . . . . . . . . .. .43 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..

15 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. .27 . . . . . . . . . . . . . . . . . . .. 13..... Tr

16 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. Tr . . . . . . . . . . . . . . . . . . .. .26 76..... O1

17 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. .06 84..... .05 55..... Tr

18 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. .82  .48 08 . . . . . . . . ..

19 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. .10 1 85 . . . . . . . . . . . . . . . . . . . . . . . ..

20 . . . . . . . . . . . . . . . . . . .. 01 .04..... O4 . . . . . . . . . . . . . . . . . . . . . . . .. 19

21 . . . . . . . . . . . . . . . . . . . . . . . ..I 09 Tr. . . . . . . . . . . . . . . . . . . .. 11  .01 72

22 . . . . . . . . . . . . . .. .06..... 228 . . . . . . . . . . . . . .. .08 01..... 07 .73 26

23 . . . . . . . . . . . . . .. .06 .11 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. Tr. 44

24 . . . . . . . . . . . . . . . . . . .. 1.33 . . . . . . . . . . . . . . . . . . . . . . . .. 16..... 04 . . . . . . . . ..

25 . . . . . . . . . . . . . . . . . . .. 01  Tr. . . . . . . . . . . . . . .. 01 . . . . . . . . .. 12.....

26 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. Tr. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. Tr 

27 . . . . . . . . . . . . . .. 02..... Tr. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 05.....

g3 . . . . . . . . . . . . . .. 05 .92 10 5.66 10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..

30 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. Tr. . . . . . . . . ..

31 . . . . . . . . . . . . . . . . . . . . . . . .. .06 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. .01 01

Total . . . . . . .. 92 2 53 6 58 2 11 4 12 2.21 2 98 21 1 14 1 64 92 5 33

DESCRIPTION OF SOILS.

The soils used. are described below. Table 3 shows their chemical
composition :

3341. Yazoo clay; from McLennan county; six miles east of Waco.
Very go-od soil; bottom land, but not subject to overflow. Produces one-
half bale of cotton, 45 bushels corn, and 40 to 5O bushels oats.

3335. Houston black clay; depth 0-12 inches. Very good land.
From Waco, McLennan county. Produces one-half bale of cotton and
35 bushels of corn. Packs, dries into clods, and does not wash; dirt
does not Wash onto it; sticky.

3333. Houston loam; depth 0-10 inches. Four and one-half miles
from Waco, McLennan County. Good soil, upland, rolling prairie.
Sufliers from drouth. Produces 25 to 30 bushels of corn and one-fourth
to three-fourths bales of cotton.

19-56. Sand from E. J. Kyle’s farm, between College and Bryan,
Brazos county.

1580. Houston black clay loam; depth 0-6 inches. From five miles
south on Goliad road, San Antonio, Bexar county. Good uniform land,
and produces 50 bushels of corn.

157?’. San Antonio clay loam; depth 0-6 inches. From seven miles
south of San Antonio, Bexar county. Virgin, poor, rolling, and is
slightly gravelly. Produces one-half bale of cotton.

Afotsrtinn RELATIONS or Sour: TEXAS Sorts. 11

TABLE 3.—-COMPOSITION OF SOILS.

O
421"" MIDI.‘ ‘Q “ M
"as s“; $3?!’- Ewe s: we

@213 55% es 32s 25E as
._ ___

g5 ,,,< emf}, EU g '42; g; Sir-l 8
e 2= ‘v4.56 3:132 = =-¢; U...“
=>='"¢“ °wug ‘"0 M115 8>=o 00B
<3g§w 3w: wgg 3H0 mew o?“

u-t "‘ "‘

gUho $2? 5...‘ gee: 20B gée
m I m E I W

I

Surface. Surface. Surface. Surface. SurfacejSurface,
5 8 1956 3333

1 77 15 O 3335 g 3341
Percent: _
Phosphoric Acid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .04 .02 .11 .25

Nitrogen . . . . . . . . . . . . . . . . . . . . . . .. .03 .11 .03 .03 .12 .15

Potash . . . . . . . . . . . . . . . . . . . . . . . . . . .25 . 52 .07 .21 . 79 .70

Lime . . . . . . . . . . . . . . . . . . . . . . . . . . .. 31.92 2.30 .33 .17 3 30 3.09

Magnesia . . . . . . . . . . . . . . . . . . . . . . . . .55 .58 .06 .17 1 12 .41

Alumina and Oxide 0f Iron . . . . . . .. 3.33 8.24 1.01 2.73 11.67 7.59

Insoluble and Soluble Silica . . . . . . . . 32. 95 79.22 98.07 94.84 69. 78 75. 08

Loss on Ignition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.49 8.25 . . . . . . . .

Moisture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .54 4. 60 3. 24
Parts Per Million: 
Active Phosphoric Acid . . . . . . . . . . . 1 41 84 75 21 38 1117

Active Potash . . . . . . . . . . . . . . . . , . . . . 207 657 106 155 45 998

Acidity . . . . . . . . . . . . . . . . . . . . . . . . . ‘ 0 11 . . . . . . . . 0 0 O

Acid consumed . . . . . . . . . . . . . . . . . . . l 100 68.7 3.9 3.4 52. 9 41.1

Water capacity . . . . . . . . . . . . . . . . . . . 34. 6 40. 7 26. 5 28.2 43.8 45 . 0

CURVES SHOWING RELATIONS:

Curves are here prescribed shoxving‘ the moisture content of certain
of the soil samples. Figures 1, 2 and 3 show the water content of all
the soil types for 1911, though not all the treatments given. Figure 1.
also shows the rainfall during the period of observation. Figures 4
and 5 show the ivater content of the fine sandy soil and the Houston
black clay for 1912. and Figure 5 also shows the rainfall. As the curves
were remarkably similar in appearance, it Was not thought necessary
to draw them for all the cans or for all the types in 1912. The circles
drawn on the curves show the dates of water percolating through the soils.

TEXAS .Xe11IcI:I.TL‘RAL EXPERIMENT STATIOX,

20 ' ‘l2 F/NE SANDY Se/L

,8 K N  p1 1 1
l6‘ 1 w  w 111M161
,2   ~ w \ 1

5 V\/ V \/ w

 Fmsum-Zl '

16

,2  O0 91 swfiji
,8 ‘kg  7K m fi§%yyf
16  y |

IVA Y

JUNE

JULY

w
1i

AUGUST SEPTEMBER ocrvafin - /v0|/£MBER DECEMBER
19/1 *

Fig. 1—\\'ater Content of Soils, 1911

Molsm

1;»?

WNW
l\J\/q

xvifi/
\\/\/

v
k .
Y \\ [PM . w
A w V V a fi
Q =2... A06 W W
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/”Jmv 7117mm N: w
A\ m \ X a
w d m w u
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a u M u u m. n. h“ u v .

rl-g/fz-"Prznaea Ocrossa Arm/snack oecanaé
,_ _ . - A

14

MNM

1k MOW/R ‘J/

wi/w/

Ek NOVEMBER DECE/“Ififk. J

\/\J
Fveurez. 5

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Y
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 v “EV V VQ.
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Q-“THIIIIIPI A OAR

‘\\ MAY

PER CENT‘

Fneuns 5

\

1\>[01sTLrRE RELATIONS OF S0111: TEXAS Sons.

 

Fig. 4—Water Content of Fine Sandy Soil, 1912

Ho u: ra/v

    

/9/Z

Fig. 5—Water Content of Houston Black Clay, 1912

16 TEXAS AGRICULTURAL EXPERIMENT Srarrox.

The curves show clearly the effects of cultivation upon the water
content of the soil. The cultivated soil contains a larger percentage of
water in practically all cases.

The curves also show the decided drop in water content during the
dry periods, and the gain during the wet periods. Figure 1 shows a
much more rapid fall in water in the fine sandy soil, during June, 1911,
than in the Houston black clay loam. The lime also renders the sandy
soil more retentive of moisture. The decided differences in the moisture
held by the various soils is also shown.

Percolation through the soil before it is saturated is shown especially
by the fine sandy soil and the San Antonio clay loam. The Houston
black clay loam and black clay seldom become sufficiently saturated to
allow percolation during the crop season.

Further discussion of the results embodied in the curves and in the
tables are given in the subsequent sections.

LIAXIMUIVI WATER CONTENTS OF SOILS.

The finely pulverized soils were placed in the evaporation cans, sat-
urated with distilled water, and placed out of doors on May 1, 1911.
On May 5-3- and 3, there was a rain amounting to 1.05 inches. The
water content of the soil at this time reached a maximum with some of
the pots that was never again attained, and this is especially noticeable

in the case of the sandy soil, No. 1956. The curves bring out this fact -

clearly. The soils at this time were not under field conditions, so that
this water content may be regarded as abnormal.

“Table 4 shows the water contents of the soil at the end or near the
end of the wet periods. The water co-ntent was taken on the same
dates, and is not always the maximum for all the soils.

‘MDISTWJRE RELATIONS of SOME ‘Ilsxxs 8011s.

   

   
  

 

. . . _ . . . . . . . . . . .

88.82 8882 88.82 82 .82 82 82.82 88.82 82.2 88.82 88.82 88.82 88 ..HRxHHMHHHHMHHHH=8 8888882826
88.2 88.82 82.82 88.82 8.8.2 88.2 88.82 88.82 28.82 88.2 88.82 88 . . . . . . . . . . . . . . . . . . ... =8 88888828226
88.82 28 82 88 82 82 82 88 82 88 82 82 82 88 82 88 2 88 2 88 82 88 8888282288 882 8888
88.88 8888 8888 88.88 28.88 2888 8888 2 .88 8888 2 H88 8888 88 3.x . . . . . . . . . . @888 F8 88883826

8.88 88.88 88.88 88.88 82 28 88.28 88.28 88.88 88.88 28.88 88.88 88 . -8818 888828226
88.88 82 .88 88.88 88 .88 88 88 88.88 88.88 88.28 88.88 88.88 88.88 88 .888. .=8 888828226
88.88 88.88 28.82 88.88 8888 88.28 28.88 82.88 88.88 88.28 88.88 88 . ...=8 88882826
88.88 82.88 88.88 88.88 88.88 82.88 88.88 88.88 82.88 28.28 28.28 88  .=8 888838226
82.88 8.88 88.88 88.88 88.28 82.88 88.88 88.28 28.88 88.88 28.88 88   .88 88882826
88.88 88.88 88.82 88.88 88.88 88.88 88.88 88.88 22.88 28.88 88.28 28  PM =2 88882826
.888 88 88 88 82 88 88 88 88 88 88 28 88 88 88 88 88 88 82 88 28 88 . ..8888>28_=8 882 2888
88.88 8888 8888 8888 88.88 88.88 8888 8888 8888 8888 8288 82 xxmfi..wpfl...8.s .=8 88882826
88.88 88.88 88.88 88 .88 88.88 88.88 82 .88 88.28 88.88 88.88 88.28 2 . . . . . . . . . . . . .=8 88882826

82.88 82 88 88 28 88 88 82.88 88 88 88 88 88 88 28 88 88 88 88 88 82 . . . . . . . . . . . . . . . . . ..8888>282=8 882 8888

82.88 82 88 88.82 88.88 88.88 88 88 88.88 8888 8888 2888 8888 82 . . . . . . . . . . . . .. ..§8..=8 88888888886

88.88 88.88 88.82 88.88 88.88 88 88 88.88 88.88 88.88 88 88 88 88 2 . . . . . . . . . . . . . .. 88.8 :8 8888882826

88.88 88.88 88.82 88.88 88.88 82 .88 88.88 88.88 88.88 8882 8888 82 . . . . . . . . . . . . . . . . . . . s8 88882828286

88.88 88 88 88.88 88.88 88.88 88.88 2.88 88.88 82 88 88.88 88 88 82 . . . . . . . . . . . . . . . . . . . 1.8 88882826

88.88 88.88 28.82 88.88 88.88 88 88 .8888 88 88 8888 88.82 88.88 82 . . . . . . . . . . . . . . . . . . . . 5.8 8888882826

88.88 88.88 88.82 88.88 2.88 88.88 88.88 88.88 88 88 88 82 88.88 22 . . . . . . . . . . . . . . . . . . . . 8888282288 882 882

28.88 82 .88 8882 2828 88.88 8888 28.28 88.88 8828 8882 88.88 82 . . . . . . . . . . . . . . . . . . . . 1:8 88.88.2826

88.82 88.88 _88 82 88 88 88.28 88 28 88.28 88.28 88 82 88 82 88.88 8 . . . . . . . . . . . . . . . . . . . . 8888382288 882 882

88.82 88.82 82..82 8882 8882 88.82 8882 882 8882 8282 8888 8 . . . . . . . . . . . . 8s: .888 v.8 88882826

88.82 2882 88.82 28.8.2 88.82 88.82 88.82 88.82 82 .82 88.82 28 88 8 . . . . . . . . . . . . . . . . 88818 8888882826

88.82 88 82 2.8.82 88.2 88.2 82 82 88 2 88 82 88.88 88.82 88.82 8 . . . . . .. . . . . . . . . 8E: =8 8888282826
82.82 88.82 88 82 28.82 88.82 88.82 88.82 88.82 88.82 88.82 88.2 8

88.82 88.82 88.82 88.82 88.82 82.82 88.82 28.2 88.2 28.2 8882 8

88.82 88.82 88..82 88.82 88.82 8882 88.82 822 88.2 88.2 88.82 8 .

88.82 88.82 88 82 88.82 88.2 88 82 88.82 88 82 28.82 88.82 88 82 8 . . . . . . . .. . . . . . . . . . . . ..=2 888888282286
88.82 88.82 88.22 88 82 88 82 88 82 28.82 88.82 88 82 88 82 82.88 2 . . . . . . . . . . . . . . . . . . . . .8888z.:=8 882 8882
22282 - .

.8 888,2 8282 8282 8282 .8282 . 8282 8282 2282 . 2282 . 2282 2282 .82 .__82882:..8Q 82
8.288888 .82 .8882 .82 .880 .88 .8888. 8 8822 88 .8822 .22 .8822 88.8882 88 82282. 82 .223. .8 >822 882 .882
882.882.8838

8820282222 EH25 k0 WQZH E< 822cm 22 HHF<>P k0 HUFHZHUGHQILQ 22.28252.

18 TEXAS AGRICULTURAL Exrnanrnxr Srarrox‘.

It will be noted that the water content of several of the soils on
May 3, 1911, is greater than at any subsequent. period. This is par-
ticularly marked with the fine sandysoil, No. 1956. With certain of
the other soils, the maximum water content approaches this quantity,
a.nd in a few cases e-ven exceeds it, which is the case with Yazoo clay,
No. 3341. We conclude from these observations that the stirring and
pulverization which preceded the introduction of the soil into the pot,

in most cases, increased its capacity to retain “rater, which water-hold- '

ing capacity of the saturated soil became reduced upon the subsequent
drying and compacting to which the soil was naturally subjected in
the pot.

With the sandy soil, No. 1956, there is noted a tendency toward a.
decreased xvater-holding capacity of the soil. However, this may be
p-artly due to the fact that the soil (lried out very much in the latter
part of 1912, and required some time to again become fully saturated
and had not reached the condition of saturation when the observations
were discontinued. As will be shown later on, xvater percolates through
these soils before they are fully saturated.

TABLE F.-—WATER IN SOILS AT ENDS OF WET PERIODS AND .WATER CAPACITY

Average Per cent Maximum Per cent

 

Lab. Description of Soil. Water Per cent of Water Per cent of Water
N0. Capacity. Water. Capacity. Water. Capacity.
1956 Sandy so1l._ . . . . . . . . . . . . . . 26.5 13 88 52. 14 65 55
1577 San Antonio loam . . . . . . . . 34. 6 19 86 57. 21 98 64
1580 Houston black clay loam. . 40. 7 24 68 61. 28 15 69
5335 Houston black clay . . . . . . .‘ 43.8 26 12 60. 28 88 66
3341 Yazoo clay . . . . . . . . . . . . . . 45.0 25 55 57. 28 66 64
3333 Houston loam . . . . . . . . . . . . 28.2 , l6 66 59. 17 79 63
Average..... . . . . . . .. 36.5 ‘ 21 12 5s. 2s 35 s4

Table 5 shows the average water content of the soils at the ends of
wet periods and the water capacity of the soil, together with the per cent.
of the water capacity held by the soil. We dete-rmine the water capacity
by placing 50 grams soil in one and one-half-inch carbon funnel, sat-
urating with water, and weighing after the excess of water has dripped
through. The average. water held by the six soils is 58 per cent. of the
water capacity. The maximum percentage of water found in the soil
(exclusive of that on May 3, for the reasons already given) is also pre-
sented in Table  The quantity is not widely diiterent from the
average found at the ends of the wet periods. We must note that the
soil never appro-aches the condition of saturation reached in the lab-
oratory, even after continued rains, the maximum found being 69 per
cent.

According to Briggs et al., Bulletin No. 230, Bureau of Plant In-
dustry, the amount of water in the soil at the time of the wilting of
certain crops, is equal to the water-holding capacity of the soil minus
21 divided by 2.90. This calculation is probably only approximately
correct.

MOISTURE RELATIONS or SoME TEXAS Sorts. 19

TABLE 6.—AVAILABLE WATER OF SATURATED SOILS. (PER CENT.)

 

Q

+43 .

i g5 10-4 E

L b r ' a? ‘t 2 ‘"  ‘i 5'4 3g

a . D ' t'o Soil. no“ v o n o ... o 3-

No. ‘ “ °   gr. a s33 gs  a

En. 20-43 g3  o3 g3 52
1956 Sandy soil . . . . . . . . . . . . . . . .. 1.9 13.9 t 12.0 12.6 14.7 12.8
1577 San Antonio clay loam. . . .. 4.7 19.9 15.2 15.9 22.0 17.3
1580 Houston black clay loam. .. 6.8 24.7 17.9 18.8 28.2 21.4
3335 Houston black clay . . . . . . . . 7. 9 26.1 18.2 19. 1 28.9 21.0
3341 Yazoo clay . . . . . . . . . . . . . .. 8.3 25.6 17.3 18.1 28.7 20.4
3333 | Houston loam . . . . . . . . . . .. 2.5 16.7 14.2 14.9 17.8 15.3

Table 6 shows the wilting points and the available water, calculated'

by this method, based upon the maximum saturation and upon the
average water content at the ends of the Wet periods. It will be noted
that there is considerable variation in the available water held by the
different soils. This fact is brought out still more clearly when we
express the percentages in terms of bushels of corn which this quantity
of WHIGI‘ would. be able to produce. In making this calculation, we
assume that one b-ushel of corn requires 38,000 pounds of wa.ter for the
production of leaves, stalk, co-b, a.nd grain and that all of the water
goes towards the pro-duction of the corn, none being lost by evaporation.

With a soil depth. of 14 inc-hes, which would usually weigh four mil-
lion pounds per acre, 1. per cent. of water would be equivalent to 1.05
bushels of corn, or 13 pounds of lint cotton, or 0.7 bushels of wheat,
or 1.5 bushels of oats, or 130 pounds of hay. According to these cal-
culations, the so-ils in the average wet condition after heavy rains,
Table 6, retained enough water, to a depth of 1-1 inches, for from 12.6
to 19.1 bushels of corn, or from 156 to 23/; pounds of cotton lint, the
quantity held varying with the nature of the soil. The plant draws
moisture from a greater depth of soil than 14 inches, but, on the other
hand, there is a considerable loss of water by evaporation. For a crop
of 60 bushels of corn, the roots of the plant must draw water from a
depth of 56 to 70 inches, if we exclude both rainfall and evaporation
during the crop season.

THF. EFFECT OF CULTIVATION AND BIANURE UPON WATER HELD BY THE
SATURATED SOIL.

Table 3 shows the water content at the ends of the wet periods of
the ten pots receiving difierent treatments. The average results are
summarized in Table 7. The effect of cultivation is uniformly to in-
crease the quantity of water retained by the soil. The soils cultivated
to the depth of four inches in two cases retain less and in one case
retains more than the soil cultivated to the depth of two inches. Cul-
tivation to the depth of one inch makes the soil less retentive than
the cultivation to the depth of two inches in two cases. The addition
of lime increases the retention of water in one case and decreases it in

20

TEXAS AGRICULTURAL EXPPJRILIENT STATION.

....@ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..- ¢@.¢%\ - . . . . . .. ... - . . . . ..  . . . . . . ..  .... . . . . . . . . . ....ENO@ nmowmgmvm 

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Morsrum; REI1;\TIOXS or Sour: TEXAS Sons. 21

the other. The addition of excrement increases the retention of the
water in three of the four instances. The increase in quantity of excre-
ment added in one case caused an increase in the retention of water.

The differences are not large, but are sufficient to indicate that the
stirring and the addition of manure makes the soil slightly more re-
tentive of water at the ends of wet. periods, e-ven when it is in what may
be termed a field saturated condition. Undoubtedly, under field condi-
tions, the stirred soil has the further advantage of holding the water
from flowing off, until a portion of it. has had time to penetrate. On
a hard, untille-d soil, water may flow off long before the soil has absorbed
much water. This is particularly the case when the rains are heavy,
as under the climatic conditions of the South.

“UXTER AT END 01-‘ DRY" PERIODS.

Table 8 shows the percentages of water at or near the ends of various
dry periods. Some of these dry periods were sliort, while others Were
of long duration. The minimum water conte-nt in 1911 was reached on
September 21, and the minimum water content in 1912 was reached on
October 1+1.

TEXAS AGIITCULTURAL EXPERIMENT STATION.

9..

  

 

   
 

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00.22 0v002 00.0 00.0 00.0 00.22 00.m2 02.02 0v.m2 m0.02 02.02 00.m2 00.22 00.02 20.02 0  ......T..RM:0 2.3020220
00.m2 20.v02 0v.02 00.0 00.0 20.m2 00.m2 20.v2 00.02 0m.v2 00.02 00.m2 00.m2 00.02 00.v2 v . . . . . .. tv 260m>002:0
00.m2 02 .202 00.02 0m.0 m2 .0 00.22 00.m2 02 .v2 00.m2 0m.v2 00.02 00.02 00.m2 00.02 00.v2 0 . IL . ...:m 2.3020200
00.22 v0.202 00.0 v0.0 00.0 0v.22 00.m2 v0.02 00.02 mm.v2 00.m2 00.m2 00.22 20.m2 02.02 m  ..... 11:2 2.303030
00.02 m0.2v2 00.0 v0.0 00.0 00.0 20.m2 00.02 0m.22 00.02 00.m2 00.m2 m0.22 00.22 00.02 2 . . . . . . . .2.o0w>002:o 82 0002
. m202
6mm m202 .v2 m202 m202 m202 m202 m202 m202 2202 2202 2202 2202 2202
Lo>< 2392. .02 .020 .02 .02 .02 .00 .m2 .0 .0 .0.0oC 2m .02 .0m .oZ dofiniomvfl .072
.>o72 ~09» .0000 02:2. v5.2. >022 .09.» .502. 60C S?» 000.0 .0:< e252. 0on2 .000
0on2 0on2

0005203 >029 KO MQZH F4 ‘=00 722 22.2.0200? HO NU<HZH0~2Hh|L0 H0000?

 

l\I0IsrURE RELATIONS or SOME TEXAS SoILs. 

Table N0. 9 shows the Water content of the various soils at the ends
0f dry periods, the average content and the minimum in 1911 and the
minimum in 19172 being given. The average of the periods ranges from
410 to 50 per cent. of the water capacity, or, on an average, 44¢ per cent-
of the Water capacity for all soils. The minimum of 1911 ranges from
33 to 46 per cent. of the Water capacity, or an average of 40, which is
only 4- per cent. below the minimum average for all. The season of
1912, however, was decidedly dry and the minimum ranges from 21 to
~11 per cent. of the water capacity, the average being 31. It will be
noticed that soils Nos. 1956 and 1577 dried out to a much greater extent
than the OthQTS, which appear to have been much more retentive of
Water. All of this table refers to the uncultivated soils.

.AxGRICULTURAL EXPERIMENT STATION .

TEXAS

24L

Z 2 m: d Z _ m: 2.: we I E .......................... 
5a m6 p: v.2 ad“ mfg 0.: mim . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..Emc_:c~m=ow~ mmmm

ch vb >43 v8 5m.- w.o~ 52 mix . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .....>m_uoo.~.m> Gwmm

fi-a        ~ » . . - - . - . » - . - | - - . - - . - - . . - - - - - ~ .    

"Iw        ~ - - n . ~ I - - ~ . - » - ~ > . ~ u ¢ - - . ~ ~ - -     

m6 9m miw miw m.: md 0.: n6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..Emo_>w_uoEo¢=<:mm hhmw

o6 w.m uh m6 9: 0d mdfi m; . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ........:ow>w:mw wmmfi
N22 ¢E2E>< ifioh. ¢zw=w>< _ 450B .@E2€>< _ .12.?
:36 .3 , 4.26m i.» .3 coiaiuwofl .oZ
Biflmmcm 422 :30 :2 Jfiw vwm$>< v55?» 4E4
CMOU 5m Ezcnxmg 525182

diOfimflh NMG hO mnzm H< MHHZS? MAQ<A~<><IHQ~ EAMFH

U!

Morstrnnn EELATIoNs OF SOME TEXAS Sons. 2

Table N0. 10 shows the available Water at the ends of the dry periods
in the uncultivated soils. The average available water ranges from 9 to
13.4 per cent. The minimum available water in 1911 ranges from 6.5
to 11.3 per cent. Soils No. 3333, Houston black clay, and No. 3335,
Houston loam, were the most retentive of moisture. The minimum in
1912 ranged from, 3.6 to 9.3 per cent. of available water. This is a
very 10W minimum and shows that the soils have dried out very thor-
oughly. Soils N0. 3335 and N o. 3333 were still the most retentive of
moisture.

EFFECT OF TREATBIENT UPON THE NVATER CONTENT OF ‘THE SOIL IN DRY
PERIODS.

Table No. 11 shows the average Water content of the soils at the ends
of the dry periods, including all of the pots Wltillillt? various treatments,
the treatment being indicated by the symbols at the head of the column.

26 TEXAS AGRICULTURAL EXPERIMENT STATION.

mmmm van “SH E036 mwmhw><
. . . . . . . . . . . . . . ‘ . . . . . . . . . . . . . ..  .~......<._--.... ....-.....  .......-¢.  

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. NTQ   omfifi  wad; .................€wo~:o~m=oE

  . . . . . . . . ..  . . . . . . . . ..       \mN—OOONfl>

. . . . . . . . . . . . . . . . . . . . . . . ...       .. .. >~wTvxOmwimflQfiwgQm

. . . . . . . . . . . . . . . . . . . .   . . . . . . . . . .    . . . . . . . . . .  . . . . . .ENO_ ~WQ_O MQONT~ QOHMUOE

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...      

. .. . . . . . . . . . . . . . . ..         . . . . . . . . . . . . . . .. zOw Z@GN@

.88 . .
tmé fl .2N QXO JQQ 6K0 .2N 6X0 .\\N  ,IN :w IV IN zfi AvQHNkwM-Zimw  *0 GOSQEOmQQ
wwflwfifisU wMXE/SEU wfimk/SEU Quit/SEQ wofint/fii-U waif/EEO wwfit/SEU ufimfiisu wfimfifisU ~02

dQOEm-m wmnho MQZHEQ FZHHZOO QHQQQP HU<MH><|J~ mqm<e

Morsrunn RELATIONS or Soun TEXAS Sons. 2'7

Cultivation to the depth of one inch increased the xvater content of
both of the soils subjected to this treatment;

Cultivation to the depth of two inc-hes increased the water content of

the soil at the ends of the dry periods on five of the six soils in this
experiment. The average increase is 2.3 per cent. This is equal to
about .62 inches of rainfall saved over the untreated soil, or a. quantity
of wrater sufficient for 2.4 bushels of corn. This, however, does not reap-
resent the entire saving by cultivation.

The cultivation to the depth of four inches also- increased the quantity
of ivater held, over both the uncultivated pots and the pots cultivated to
the depth of two inches, on the three soils subjected to this treatment,
The difference. however, is slight. The stirred portion of the soil prob-
ably dried out, and as four inches of dry soil would be a considerable
proportion of the soil in the can, we should judge that the water con-
tent of the unstirred soil is considerably larger than that in the soil
stirred to the depth of two inches, the difference being greater than the
amount expressed in our figures, on account of the drying out of the
four inches of stirred soil.

The soil stirred to the depth of six inches contained less water than
that stirred to the depth of two inches, but the stirring saved some
water. As the six-inch la.yer was undoubtedly drier than the remainder
of the so-il, the content of the unstirred soil must be decidedly higher
than the figures presented.

The addition of lime increase-d the water content over the soil stirred
to the depth of two inches, in one case quite decidedly, a.nd in the other
case not at all.

The addition of excrement increased the water content of the soil over
the soil stirred two inches in three of the four soils to which it was ap-
plied. In one case there was a decrease. Lime and excrement was little
more beneficial than excrement alone- in one case and more so in another
case. 'I“he additio-n of excrement and stirring to the depth of four
inches increase-d the water content over the soil stirred to the depth of
four inches very decidedly in the case of soil No. 3331. The larger
addition of excrement increased the water content slightly’ over the
regular quantity applied.

Table No. 12 shows the minimum water content of the soils at the ends
of the dry periods of 1911 and 1912.

;I:I1[E.\'~1‘ STATION.

28

TEXAS AGRICULTURAL EXP!

 . . . . . . . . . . . . . . . . . . . . ..
Nd  wéfi .. . . . . .. m.w
. . . . . .  wd
....mwnmw.wnw..@.@ 
  Nd n6
A
.012 W ~13 .. mu;
   val
gwwninxumu:92:zfifi:
. . . . . . . . . . . . . . .. N.: N.:
.36 f dxfl 3mm dxm
1% \\.V t§

 i. Wm . . . . . . . . . . .  . . . . émfio><

NAM .   a..w . Nd ...N . . . . . . . . . . . . . ‘ . . . . . . . .......Em0~.flQ~m=om mmmr.

..  7x _ 9w m8 Nfim. v6 mi . . . . . . . . . . . . . . . . . . . . ..........%a_oooNwV fivmn

- . . . . . - . . . . . .._.......  . . . . ._. %.%  . . . . . . . . . . . . . . . 4 . . .....>m:U VQUN@Q iofimmwnuz 

 . mic O6 wé . . m6. wd . . . . . . . . . . . . . . . . 15mg ha? 3on3 cofinom Qwmfi

. ... ..... ....  ...... mw.%w Rxw . . . . . . . . . . . . . . . . . . ..ENO~%N~U O@GOHQ<CN@ 

Nd wé m8 m5 n6. ha... m." . . . . . . . . . . . .  . . . . . .  . . . . . . fiomhwcmm 0mm"
NEH 3 .30 E Escaig
m1: m.w . . . . . . . . . .  . . . . . .  . . . . . Iowm$><

Aim  m5 .. . . vdfi miN . . . . . . . . . . . . . . . . . ...........Emo~co~w:o~|~ mmmm

 #3: 0.: T: mtm NZ“. m.w  . . . . . . . . . . . . . . . . . . . . Iihwfivoonm? Zwmm

1100010. --¢-.. <~a-u--  . . - - . - ».  mu“ . - » . . - ¢ . - . - . .00 . . . - ~ ¢ -.%N?o   

-.-..-¢    . - . - - . .. §-% %-£ .. - . . . . . . . - . - ...-E“Q?    

--¢-.. - - . . - - .. ---¢-¢  . ¢ Akvn$ §~-€ . . - . ¢ . . . . . - . - - . .-»¢-Eflo%    

fi-v? §-a   §-i mom m»? - . - - -.- - . - . . - . - .-u.on¢-.nu-.-i.@om  
6E5 J50.» .32 .§ flaw .3 EsEmi§ dZ
1m to 2v :m i :0 3:56 had

dflOwiflm WMQ HO MQZH HQ. mamas; mum<u~<>< EDuAE/izlkww HHMFH

lUOISTURE RELATIONS or SOME TEXAS SorLs. 29

With the exception of soi.l No. 3333, Houston loam, stirring to the
depth of two inches saved. quite a decided quantity of water during both
of the dry periods. Stirring t0 the depth of four inches is in one case
in 1911 more beneficial than two inches, and in two instances in 1912,
three soils being cultivated in this wvay. The soil on which it had a
beneficial action in 1911 did not show the beneficial action in 1912.
Stirring to the depth of six inches is less effective than stirring t0 the
depth of four inches. The addition of lime was beneficial in one of
the two cases in 1911, but not in 1912. The addition of excrement was

beneficial in three of the four cases in 1911, and in 1912, soil No. 3335,,

Houston black clay, in each year showing little benefit. Lime and
excrement are no more beneficial than excrement alone in the two cases.
Four inches stirring with the excrement added is more beneficial than
the four inches alone in both years.

Table 13 shows the gain of available water as expressed in bushels
of corn or pounds of cotton per acre.

3O TEXAS AGRICULTURAL EXPERIMENT STATION.

   

Q o A o o o o  .................. .._.__w..:=é=.m mam
@N   i. .3 Q-m cum i i . - - } i ~ 1 - > i > i i i . - 4 . 1 - @ i § - Q - - i  .  - . .  1 . . . -  - 1 . ~ - - - 1 . - . - . . . - o   
fix   _ % . N § ¢ m o -% . . . - - - . - . - ¢ - . . . . . . . . . . . - ¢ - - _ - - -    
Qw   § -o a - 7 w a fi - - . 1 . . . . . . . . . - T . @ . . .  . . . . .  . . . . . . . . .  . - . .~. . - 0     
mm wv om mA 5m 0d    . . . . . . . . . . . . . . . . . . ..Ewo_>m_no@=o~c cmm 5.2
mm  b m-N Ya? mac . - - - . . . - . . - - - . - . . . - . . - - . . . - ~ . . . . . ~ - . . - Q - » - - - . - - - - » | ~ - a -   
m2: :2 oww$>< Q2 22 “$2034 v

ESEMGUZ 8581i; S58E52 Esimfiz .o Z
Awwcsomv cofioU Ammvnwsmv E00 don Ho nomwniomufl dud

20,500 QZ< ZMCO Zm DHQMHMHKH .mwmoz_ O3? ZOHH<>HHADU MM EH84? HHM<H~<>< hO Z~<U|é~ @555.

Uorsruan RELATIONS or‘ SOME TEXAS SoILs. 31

The gain in 1911 varies from 0 to 3.7 bushels of corn, and in 1912,
from O to 2.5 bushels. The gain of cotton lint varies from 0 to 48
pounds in 1.911, and 0 to 33 pounds lint in 1913.

These gains are the differences in water content due to cultivation of
the soils. As, however, the gains are co-ntinuous from day to day, and
the differences are from time to time equalized, at least to a ce-rtain
extent, by rainfall, the actual gain would be really much larger than is
expressed by the above figures.

According to the results secured in Bulletin No. 1'71, with the perco-
lation apparatus, cultivation was much more effective in retaining water
and decreasing percolation in the sandy soils than in the clay soils.

According to the work here- reported, cultivation decreased evapora-

tion in all the so-ils. We have not yet decided on the explanation of ~

the discrepancy. Most of the percolation takes place during wet periods.
The percolation should depend to a certain extent, upon the extent of
drying out during the previous dry period. It also depends, however,
upon the rapidity of penetration through the soil, as a saturated soil
loses water much m.ore rapidly than a soil that is not saturated. The
clay soils have a tendency to crack during dry periods, fissures being
produced which allow the water to penetrate rapidly. This fact may
affect the percolation decidedly; the rate of penetration of the water
may affect the total percolation.

LOSSES OF IIOISTURE.

Table N o. 14 shows the losses of moisture from the pots during the
various dry periods with the exception of September 21 to October 9,
and October 9\to~ December 5, when there were gains due to the water
falling during these periods. These losses represent the loss by evap-
oration and not the loss by percolation, as they are based entirely upon
the weight of the pots. Table 15 shows the gains during the various
wet periods with the exception of the period ending July 25 to March 30,
when there were losses. These were not included in the average, but
are placed at the bottom of the table.

32 TEXAS AGRICULTURAL EXPERIMENT STATION.

  

         . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  . . . . . . . .....®wNH®»/<

NN 9“ 8 N? “N? S fi 3% 3.8 RNNNS. NQE mwwm E . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 480k

5AM. Kim mmmm, ommm mad $4» firm owd mmé  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .>oZ S $.80

a@..m     @@-   @@. , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...........¢M .QUO  JkmOw

$5.9  G  w        7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .©w JQQW Ow  ~61:-

-@.m     Bmw. IT    _ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ... ............m.~ ~W—DA.OHMM Qflim-

         7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  OED%Ow  \mN2

ma: +         - . ' . . . - - . . . - - . - . . . . - - - . . . - - . . - - - . | n - - . - - - - - - v u  

S. Q N R.» Q N m?“ ER Maw 3m $4‘ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  . . . . . . . . ..N_ fin 8 Nz: N e2.

Ex». fix. E; S, 8N SN 3N N“: NN; . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N2: a 5N 8R 8Q

         - | v ¢ - - - ~ - - - ~ . - ~ - . - - . > . - u - - - u I - 1 ¢ - u - - ~ - u ¢ » ¢ ~ - ¢ -.?N    

         . . . . . . . . . . . . . . . . . . . . . . . . ... . . . . . . . . . . . . . . . .   OH 

Nfi G          .©m  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .®N QCUM. Ow m \mfl2
_
dam cam dxm
2N \\N \\o \\§ IN \\@ \\¢ \\$ \\O
2 M: S m: 2 _ S 2 N_ 2
mmmm mom 2W2 Ea .
._z==u=..oldom awe mo mmlezmomwm w: M53202 mo mmmmoqli mEEQ
x \ \\\_ 4 .
          . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...@WN.MQ><

hmimw. wNévm QN.NN EOJNN KNQN wwiww wmfiwn NwAVN MwJMN fiwQm. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  . . . . IEQOP

whgm 55w wwé Kmé ism aim nmd RNA Nwim bwfi . . . . R . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..m~.>oZ B ww JQO

3A ww. ow. QR. Kw. 3% E. ma. 84+ Ema. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.3.30 S wfififim

          ~ ~ . . - . . ~ . . - . - . - - - . - . - . ~ - ~ . - . - . ~ - . - - - 11w?   

@$.¢   _@@. "mwmw. @@. ¢§. @%. §@. _x@-@ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..@@  ow  @c§.@..

          . . . . . . . . . . . . . ‘ . . . . . . . . . . ... . . . 4 . .  0C5»»OwOm\mN2

Om-          - - . - - ¢ ~ - . - ~ - < - ~ - . - ~ ~ - ¢ - ~ | ~ ¢ ¢ . - - ~    

Q N t“ N 9. N R4 EN NNl MN; $4 N: NwN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . NH A? 2N =2.

R4 $4 .3. 2%. m? S; N“. RN. Nw. w». . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ....N:..H N45.

          - ¢ ~ . ~ - - ~ - . ' - . . ¢ ~ ~ - ~ | ~ Q - - ¢ - - ¢ . ~ - - - »  

   .%        - _ - ‘ . - - . - . - . . . » - R . - - . - . ... - . - - ~ - - . . - . >-o§   

          . . . . . . . . . . . . .  . . . . . . . . . . . . . . 
Sm  3m M =N . R
.:N :0 2w . tN W 25A to =v =N 1w IO
2 . N w N E w m. N m N H
R5 mow . £2 =5

ziOm awe hO HU<FZHOMHM ZH mmaefiofi HQ mmmmoqli mama.

33“

Blolstmvnr: RELATIONS OF 30MB TEXAS S011».

 

 

 

   

Eu. 3n 86a 85m flfim mama R4 2: MEN 3a . . . .  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . $mws><

E mm Ram $4; 3.2 2x2 5.8.8 Ewfi m2: 8 2 3.3.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...._8¢H

homo modfi mad wTm “m5 39m mo.m mmfw mmxm “m6. ITJ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . I»; doQ 3 25oz

E w 2Q 2+ .86 Si. 85m 3a Se“ m» m 8a . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . :32 8o 8 E .30

w»; mm...“ wwa 5m mwa Jwwa wma AWN mwa Mme . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.0m .23. 8 Bwnfi.

.. . . 28. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  w.
a... mm...“ w? s; Fm w? a... NZ N3 3N _ ................................... .:.§a2.=NH...m
2:. 8.8 MK; 9:. 8.4 8.4 B; S; woa Nflm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31$ 8Q 8 m 3Q
8.9m fie mw. S. $18. 2.8 N». . aw B. g m i . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . :2 .23 8 am 8.3

3m 3m =N .
\\§ \\$ \\§ \\§  \\@ \\Q \\§ \\% \\©
2 a w . n w . m. w m N ~
R2 E5 .5: =8
50w mme mo HUFEAHOMHN z- mmaefioi mo mz~<ul.m_ @522.
\\i\ Iii‘ \1||\l1\: .§\\v \\1h l: \ \ 8 l I \ . _ 4‘ \ _ <  v. . \ l i1? l l. .rx<ly\lz\lv\ll\ |1 yx .§\ >1, . \ l1
Qfim m»; 3d wme E Q i?» 2.8. Th8. m2. mmé . ma;  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..%.:...><

8.85m £8 2X: mm a» “w 3 =88” 8.3 1w Q E t. “N 3 m8? q . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ......._8QH

Z5 S. m wmiw £5 $4. wwi. s... a .8388. .2... .25 .35 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2 5oz 8 M: .80

         I   . . . . . . . . . . . . . . , . . . . . . . . . . . . . .  

... a... 1. .. .. .. . i. . fr... ... .1. u. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . : 8 2:.

 : wm. 38+ 5M8“. .21.. W2.» Km.» 28...“. 12;. Y5 . . . . . . . . . . . . . . . . . . . . . . . . . . . 12m QMLRW: om mww/wfl

R. R 8 3.8 N? wwn 1%; .2. am; is .2 _ 2 _ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . I3. 22 8w 82

3.; El 2m wme mfifr  F85 if. “Q? Si. Wcmé HJHMHMYHMT... .:.w. . . . . ...§.%m 889.5.
2.8 d8 a... wmw. 2.8 if. em we m 3.. E: “mm: . . . ..  a2: @882. 8 8.80
i. é. B. + 3 8. 8h i; $5 59w b.  w?» Rm; . . . . . . . . . . . . . . . . . . . . . 1:5 .38 8 2 a5»
54 2m 9km E m mma fir“. Kim. :38 $8.1m Ema am...“ XIKTTIT_.IK@III.Z€.m:<o~om>_=w
is we m Q N. 2. 3 9. 2 fiw I ‘s. m: fim 8 Tm .2 To 8 2w 2 N . . . . . :2 mm 33 8 n22
n _ 8 . it!!!

6U 68H dam . .0NM~ . ._   ..

=N =N .5 i. =N =N & =8 _ i. m i1. i W .5 .

am mm ww R wm mm .5 mm _ mm S _. 8 W

mmmm Ea 3mm Ea 

._:.==:==o|.=om Mia hO HUFHZWOMHQ Zm HMDHQFVE KO mummoqli H.582.

TEXAS AGRICULTURAL EXPERIMENT STATION.

 

o NN. N:.: o o N  N N N N N ........HmHHm“xxxxflmuummN:..h:Noom:mfiwfiww
mmm MMN WWN :N o NN Q NN N NN N NN::. w w w .. . . . . . . . . .  .. ....fl::.N.:.=.:. N: NNNENNF:
SN wwé SN 2N NNN 2N 3N NNN NNN NNN NNN ffimmxxnnmxmmnuwun . . . . . . :@.zww<
mmdm NNNN NNNN :.N.NN ::..NN :NNN NNNN NNNN NNNN NNNN :33 .. . :2 N
mmé NNHN NNHN NNN: NNN 8N NN.:: NZ: NN.:: NNN: :N.N: H.wHmmmuxmmnuxxmmmhN:8w: Qwiéwz
NNN NN N NN N NQN wv...“ EYN. NNN EN NNN NNN NNN . . . . . . . . . . . . . . . . . . . . . . . . .. N:. M: o N: N: NNNo

wad N:.N NQN N3: wad NN.:: NN.:: NN.:: NN: NN.:: 5::  fl . . . . . . . . . . . . . . . . . . . . 1N: wwN NZN N:=:.

2N NNN NNN EN NNNI NQN Dim. N:N NNN NNN 3N .... . . . . . . . . . . . . . .  . . . . . . . .. wN :¢N 1:2“. :.

No. I NNH I NN. ::. NN. I 2.. 2:1 N? NN: NN: NN. zflu . . . . . . . . . . . . . . . . . . . . . 1N WWW: JNNN. w:

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NNN NN N NN N NN N QNN NNN EN NNN :NN NNN NN.N m . . . . . . . . . . . . . . . . . . . . . . . . . . .. NNN =9. : N Tm:

NN. N? l NN. NNN NNN N:N NNN N:.N NNN NNN NNN . . . . . . . . . . . . . . . . . . . . . . . . . . . ..NNN:._:¢:::2?N
NN: NN. wwé :NN NNe NNN NNN NNN NNN N:N NNN .. . N: ::. ZN N

JWU dxfl dxm 6mm

2N \\§ \\o \\¢ QN \\x \\@ IAN IN \\% \\O

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NNNN NNN QNN =8.
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N .

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mm. O O O O mm. Ow. O 4 O  . . . . . . . . . . . .. N» O%lmiwwnNvm@w:fi

aw @.m. c a @ @ Aw aw . © . . . . . . . . . . . . . . . . . . . . . . . . . .  . . . . . . .  Na Ha

NNN NNN 8:. 2N NNN :NN NNN NNN. 3N ......::......:HHHHHmmxx . . . . . . . ...........N.NM2~:<

NNNN NNNN ¢N.NN ¢N.N:. mmbw omdw ::.:.N NNNN NN.:N . . . . . . . . . . . . . . . . . .. : : N

3N NNN ::.:: 8:: NN.:: 5:: NNN: N:w:: NN.:: . . . . . . . . . . . . . . . . . .  . . . . . . ...:...w...w.w...wflnnN:NNQSENQZ

NNN N:N wwé NNN NNN NNN NNN SN 3N ..................I.K~HIII . . . . . . . . . . . . . . ..N:NNw_oM~mT:::ww

3N owb 3:. NNN NNN NNN NNN :NN .NN.N  p . . . . . . . . . . . . . . . . . . . . . . . . .. ww Fw. N Q52

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wad NNN Nmé NNN Nae SN NNN 8+ N:.N . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..:.:..: NM»: SNNNNQ

w?“ WWW an“ ME  Wmn» ::N:NA:N: WWW MW“ fixxxwwwpwuwpm . . . . . . . . . . . . . . . . . . . . . . . . . . ..NwNN:=Noo:¢: 2E.

         . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   QM  QCQQ.

dkmm QNMM 6km 7

ZN \\§ 2O \\§ \\§ \\@ \\¢ \NX<\ _ IO

N: N: N: N: N: N: N: N: . ::

NNNN =2 QNN: =8

.:...:E=E.o|.::om Him. mo mmiezmommm .2: HNPENRVS No mziulN: “in;

Morsrunn inrxrrioxs or SOME TEXAS Sorts. 35

The effect of the- cultivation is, on an axierager, to decrease the loss of
moisture by evaporation during the periods. This is shown by consid-
ering the average results given in the table. Two-inch cultivation is
eifective in this respect in every case with the exception of soil N0. 3341..
Withthis soil, on. an average, a. two-inch cultivation shows a. higher loss
than the pot Without cultivation.

If We study the table in more detail we find that the cultivation does
not always save the water of the soil. For example, inlthe period from
August 10 to September 21, there is a greater loss from the cultivated
soils than from the uncultivated in ever_v case. The same thing occurs
with soil 1.\To~. 1956 in a period from Mfay 30 to June 1.3 with the excep-
tion of the soil cultivated to the depth of  inc-hes, and also with soil
No. 1577, but with the» other soils the loss is less from the uncultivated
soils, with some exceptions.

The gains from the soils are in an opposite direction from the losses-
That is to say, the cultivated soils having lost less moisture during the-
dry season, also gained less moisture (luring the subsequent wet season.
This rule does not follow in all cases. For example, in the period end-
ing July ‘BO, there is a. greater gain with the cultivated soils, Nos. 1580,
3335, and 3341, than with the uncultivated.

This relation of the losses to the gains is to be expected, as the soil
when saturated holds almost the same quantity of water whether culti-
vated or uncultivated, although, as we have seen, there are some dif-
ferences.

“WATER CONTEXT OF TUE SOIL TYPES.

There is a decided variation in the water condition of the various
soil types. The calculated available water of the saturated soils varies
from 12.0 to 18.2 per cent. (f’I"alile~ 6), or about 5O per cent. The aver-
age calculated. available water of the soils at the ends of the drv periods
varies from. 9.0 to i13.4 per cent. (Tahle 10), or about 50 per cent. The
variation  still more for the mininiiiiii dry points o-t 1911 and 1912.
The clay soils throughout are more retentive of moisture and for this
reason have a. higher crop possibility when other conditions are good.

On the other hand, they are more liable to sufter from excess of moisture

during »r0longed wet weriods.
. l) r: 7

ACT{'_\'O\VT.EDG)[EXT.

Vileighing" and other vvo-rk connected with the bulletin were made by

Mr. W. (7. Hainncr, J. B. Kellv, I. B. Rather, L. (l. Tiudlum, A. J1-

Weaver, and perhaps other members of the stafi.

SUMMARY AND (‘OXCTJYSIONS .

1.. This bulletin reports a study of the moisture content of six"

Texas soils, under different conditions and treatment, for two years.
.2. Curves are given showing the moisture content of the soil at
different periods and the relation of the moisture to the rainfall.

36 ' TEXAS Aonrounrnnar. EXPERIMENT STATION.

3. The average quantity of water after continued rains is 58 per
cent. of the water capacity measured in the laboratory, and the maximum
quantity is 69 per cent.

4. The soils retained when saturated to a depth of 14 inches enough
water for 12.6 t0 19.1 bushelso-f corn, or from 156 to 234 pounds of
lint cotton. The crop draws upon a greater depth of soil for moisture,
but there are also great losses due to evaporation.

5. Cfultivation and manure both increase the quantity of water held
at the ends of the Wet periods. v

6. The soils retained at the ends of the dry periods, on an average
of the two years, 44 per cent. of the water capacity measured in the
"laboratory; The lowest quantities reached in 1911 were 33 to 46 per
cent. of the water capacity; ‘in 1912-, from 21 to 41 per cent.

'2’. Cultivation increased the water content of the soils at the ends
of the dry periods.

8. Excrement also increased the water content of the soils at the
ends of the dry periods.

9. Cultivation and manure decrease the loss by evaporation.

10. There are decided variations in the capacity of the various soils

' to hold water during wet periods and to retain water during dry. periods.

There is a variation of about 50 per cent. in the soils studied.