\

564-812-5111

TEXAS AGRlCUlTURM EXPERIMENT STATIONS

BULLETIN NO. 151 A AUGUST 1912

Relation of the Total Nitrogen of
the Sail to its Needs as Shown O
in Pot Experiments OT

BY
G. S. FRAPS, ‘Chemist.

 

POSTOFFICE w
COLLEGE STATION, BRAZOS COUNTY, TEXAS

 

AUSTIN PRINTING COMPANY
AUSTIN, TEXAS
1912

TEXAS AGRICULTURAL EXPERIMENT STATIONS.
GOVERNING BOARD.
(Board of Directors A. & M. -College.)

WALTON PETEET, President . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Fort Worth

JoHN I. GUION, Vice-President . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..Ballinger

CHAS. DAVIS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Steele’s Store

L. J. HART . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..San Antonio

J. ALLEN KYLE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..Houston

R. L. BENNETT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Paris

D. W. KEMPNER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ....Galveston

En. R. KoNE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ._ . . . . . .Austin
PRESIDENT OF COLLEGE.
R. T. MILNER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .College Station
STATION STAFF.
B. YOUNGBLOOD, M. S . . . . . . . . . . . . . . . ._ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..Director

M. FRANoIs, D. V. S . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Veterinarian

G. S. FRAPs, P11. D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Chemist

H. NESS, M. S . . . . . . . . . . . . . . . . . . . . . . . . . . .' . . . . . . . . . . . . . . . . . . ; . .Horticulturist

J. C. BURNs, B. S . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Animal Husbandman

W1LMoN NEWELL, M. S . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Entomologist

A. B. CoNNER, B. S . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Agronomist

F. H. BLODGETT‘, P11. D.. .- . . . . . . . . . . . . . . . . . .Plant Pathologist and Physiologist

J. M. JonNsoN, M. S . . . . . . . . . . . . . . . . . . . .y . . . . . . . . ..Farm Management Expert

W. L. BOYETT. . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..State Feed Inspector

HARPER DEAN, B. S . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Assistant Entomologist

J. B. RATHER, M. S . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Assistant Chemist

J. B. KELLY, A. B . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Assistant Chemist

L. C. LUDLUM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..Assistant Chemist

F. B. PADDOCK, B. S . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Assistant Entomologist

H. H. JoRsoN, B. S . . . . . . . . . . . . . . . .' . . . . . . . . . . . . . . . . . . . . .Assistant Agronomist

CHAs. A. FELKER . . . . . .- . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Chief Clerk

A. S. WARE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . j . . . . . . . . . ; . . .Secretary

J. M. SCHAEDEL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..Stenographer

R. L. SPILLER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Mai1ing Clerk

STATE AGrRICIIIIPUR-AI; EXPERIMENT STATIQNS.
GOVERNING BOARD.

HIS EXCELLENOY GovERNoR O. B. CoLQUITT . . . . . . . . . . . . . . . . . . . . . . .  . .Austln
LIEUTENANT-GOVERNOR A. B. DAvmsoN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..Cuero
COMMISSIONER OF AGRICULTURE How. En. R. KoNE . . . . . . . . . . . . . . . . . . . ..Austin
DIRECTOR OF STATIONS.
B. YOUNGBLOOD, M. S . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . College Station
SUPERINTENDENTS OF SUB-STATIONS.
E. E. BINFORD, Beeville Sub-Station . . . . . . . . . . . . . . . . . . . . .Beeville, Bee County

W. S. HOTCHKISS, Troup Sub-Station . . . . . I . . . . . . . . . . . . .Troup, Smith County

E. M. JOHNSTON, Cooperative "Rice Station . . . . . . . .Beaumont, Jefferson County

I. S. YORK, Spur Sub-Station . . . . . . . . . . . . . . . . . . . . . . . . . . .Spur, Dickens County

T. W. BUELL. Denton, Sub-Station . . . . . . . . . . . . . . . . . . . .Denton, Denton County

A. K. SHoRT, Temple Sub-Station . . . . . . . . . . . . . . . . . . . . . ..Temple, Bell County
V. L. CoRY, Lubbock Sub-Station. . . . . . . . . . . . . . . .Lubbock, Lubbock County
P. D. PERKINS, Angleton Sub-Station . . . . . . . . . . . . . .Anglet0n, Brazoria County
H. C. STEWART, Pecos Sub-Station . . . . . . . . . . . . . . . . . . . ..Pecos, Reeves County

4D

. T. McNEss, Nacogdoches Sub-Station. . . .Nacogdoches, Nacogdoches County
H. C. HoLMEs, Feeding and Breeding Station. . .College Station, Brazos County

NoTE.—The main station is located on the grounds of the Agricultural and
Mechanical College, in Brazos County. The postofiice address is College
Station, Texas. Reports and bulletins are sent upon application to the
Director. A postal card will bring these publications.

(El

RELATION OF THE TOTAL NITROGEN OF THE SOIL TO ITS
NEEDS AS SHOWN IN POT EXPERIMENTS.

BY e. s. FRAPS, Chemist.

It is a well known fact that the quantity of nitrogen which can be
taken up from the soil by crops depends, to a considerable extent, upon
other factors than the total nitrogen of soil. The term “active nitro-
gen.” is used to designate the nitrogenous compounds which can be
taken up by plants-ammonia, nitrates, and certain organic compounds.
It has been shown, for example, ina previous bulletin of this station
(Bulletin No. 106, July, 1908) that the production" of active nitrogen
in the soil depends to a certain extent upon the total nitrogen of the
soil, the nature of the soil, the quantity of water contained therein,
and the nature of the organic nitrogenous compounds. It was "also
shown in the bulletin referred to, that the quantity of active nitrogen
produced was related to the growth of the crops in pot experiments,
and to the quantity of nitrogen contained therein.

It can not be expected, therefore, that the total nitrogen content of
the soil would be strictly related to the needs of the soil for nitrogen
in pot experiments. Nevertheless, we consider it of importance to study
this phase of the question, both for its own object, and also as a basis
for further work on the nitrogen of the soil. a

METHOD OF WORK.

The method of pot experiments is as described in Bulletins 127 and
145 of this station. In all cases, pots receiving phosphoric acid, potash
and nitrogen, are compared with those receiving phosphoric acid and
potash only. The total number of crops considered is 832.

The details of the individual experiments are similar to those given
in the bulletins referred to above, and are presented in table 4.

RELATION OF TOTAL NITROGEN TO NUMBER OF DEFIOIENT CROPS.

We term a crop very deficient (DD) when the crop without nitrogen
is 5O per cent. or less of that with nitrogen. If the crop without nitro-
gen is 5O to 9O per cent. of that with nitrogen, it is termed deficient (D).
If the crop without nitrogen is 9O per cent. or more of that with nitro-
gen, it is termed sufficient (S).

Table 1 shows the number of crops very deficient DD, deficient D,
and sufficient S, grown in the soils and arranged according to the soil
content of total nitrogen, and also the percentages of such crops, calcu-
lated from the total number in each group.

__4__

'I.‘.~\BI.I~I 1.-- NUMBER. OF DEFICIENT CROPS IN GROUPS ARRANGED ACCORDING TO
TOTAL NITROGEN OF SOIL. .
Number of crops. ' Percentage of crops .
DD 1 D S_ DD a D S

0-02 _________ __ ___________ 12  1 2 80 7 18
0 021-004 ______________________________________ __ 38 31 6 51 41 8
0 O41-0.06 ______________________________________ __ 31 39 13 37 47 16
0 061—0.08 ________ _- 11 18 1 36 60 4
0.081—-0.10 ____- 12 18 11 29 44 27
0.101-—0.]Z _________ __ 7 14 9 23 47 30
0.121—O.14 _________ __ 7 10 4 33 48 19
0.141—O.1(i __ __ 6 3 3 50 25 25
0.161-0.18 ___________ __ 1 s 8 20 60 t‘ 60
0.18]——0.20 _________ -_ ____ 1 5 2 12 64 29
0.201—0.22 _-_ 1
0.221—0.29 _-_ 1 5 2 12 64 29

DD—-Very deficient. D-Deficient. S-Not deficient.

There is a general relation between the percentages of. crops very
deficient 0r sufficient, and the nitrogen content of the soil. The per-
centage of Very deficient crops decreases somewhat irregularly from
80 per cent. in the soil containing .02 per cent. nitrogen or less, to 12
per cent. in the crops containing 0.22 per cent. nitrogen or more. The
percentage of sufficient crops is much more irregular, but there is a
tendency to increase with the percentage of nitrogen in the soil.

Examination of the individual experiments discloses the fact that
the deficiency is related in a general way to the total growth of the crop.

a pin’ i /Z
m efgé‘ ayep/vl/C/vps /
s ._---/
Q40
s /
8 /
Z0

0 .02 .00 .00” _.08 ./0 ./2 ./4 ./0' J8 .20
F/(i. /. 1150051101655 0F 407/9065” //v5'0/z

Fig. 1.—Ratio of crops without nitrogen to crop with nitrogen.

TABLE 2.—AVERAGE WEIGHT OF ALL CROPS WITH AND WITHOUT NITROGEN
ARRANGED ACCORDING TO NITROGEN CONTENT OF $OIL.

Average weight.

Ratio Number Maxi-

PK I PNK PK of mum

Grm I Grm. PNK crops weight

0—.0~2% ________________________________________ __ 3,4 i 17,1 2o 15 7_0
021—.04% ___ 6.1 14.6 42 79 20.0
041—-06% 8.1 i 18.9 43 76 25.8
061—-08% _ 11.0 I 20.8 53 s0 89.2
081—-10% _ 10.3 7 18.1 57 42 33.0
101-~.12% ___ 11.0 i 18.0 61 32 30.0
121—.14% 11.1 18.3 61 21 81.5
141—-16% 14.1 24.8 57 12 82.0
161—-18% 11.7 16.9 69 8 19.0
181—.20% 14.2 18.8 76 8 37.5

201-.22% 1 ________ __
221- % - 17.8 24.6 72 8 47.8
Total 332
l

___5__

As a general rule, the larger the crop with complete fertilizer, the
greater the probability of the soil being very deficient or deficient.

RELATION OF THE NITROGEN TO WEIGHT OF CROPS.

Table 2 brings out the relation of the total nitrogen to the average
weights of the crops grown with and Without nitrogen. The average
weight of the crop Without nitrogen increases with the nitrogen-con-
tent of the soil. The soils can be combined into a. smaller number of
groups, as follows:

Average weight

Nitii-ogwn in soil. (WVithout Nitrogen).
O—-.O2 per cent Nitrogen . . . . . . . . ._ . . . . . . . . . . . 23.4

0.021—~.O4 per cent Nitrogen . . . . . . . . . . . . . . . . . . . . 6.1

0.41 —.O6 per cent Nitrogen . . . . . . . . . . . . . . . . . . . . 8.1.

0.061—.18 per cent Nitrogen . . . . . . . . . . . . . . . . . . . . .1l.()-/l4.l

181-20 per cent Nitrogen . . . . . . . . . .. . . . . . . . . . .142

.221— per cent Nitrogen . . . . . . . . . . . . . . . . . . . .178

Thiiis the iveigjht of the crop increases with the nitrogen of theisoil up
to .06 per cent. nitrogen, and remains nearLv the same for the groups
.O6-—.18 per cent. This is shown graphically in Fig. 2. .

The total nitrogen of the soil is of greater significance in pot experi-
ments below .06 per cent. than it is above that quantity, so far as total
average Weight of the crops are concerned.

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0 .02 .04 .06 .06 J0 .12 ./4 .16 ./6’ .20 .22
F10. 2. P£RCZW7AG£5 0F/Y/r/PO0Z/Y m/ 50m

Fig. 2.-Relati0n of the average "weight 0f_ the crop to the nitrogen conttent of
the soil on which 1t was grown. ~

The ratio of the crop without nitrogen, to that With nitrogen, ex-
pressed in percentages, isgiven in Table 2, and shown graphically in

_5__

Figure 1. This decreases quite regularly with the nitrogen content of
the soil. That is t0 say, the effect of fertilizer nitrogen in pot experi-
ments decreases with the increase in the nitrogen content of the soil.
For example, the addition of nitrogen to soils containing less than .02
per cent nitrogen, increases the crop to five times as great. With soils
containing .021——.04 per cent, nitrogen, addition of nitrogen causes
the crop to be nearly two and one-half times as great. The addition of
nitrogen to the soils containing about 0.22 per cent. nitrogen, increases
the crop about one-third. This is shown in Figure 1-A. The distance
between the upper and lower lines represents the effect of the added
nitrogen, and it is readily seen that the effect of the nitrogen decreases
as the nitrogen in the soil increases-

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(mop: M17700!’ /V/7,?06t'/V=/00)

0 .02 .04 .06 .08 ./0 ./2 ./4 ./6 J6 .20
PfFCf/VT/Ififj OFN/THOGZ/V 0750/1

Fig". 1-A.—Percentag'e increases in crops caused by addition of nitrogen to the soil.

The effect of nitrogen upon the average Weight of crops in pot ex~
periments decreases With the total quantity of nitrogen in the soil.

TABLE 3.—AVERAGF. PFRCENTAGE OF NITROGEN IN CROPS AND‘ NITROGEN RE-
MOVED FROM SOILS ARRANGED ACCORDING TO TOTAL NITROGEN CONTENT.

- Parts of million. Corn possibility.
Number Percent Grams
Group. of crops. nitrogen. nitrogen. Maxi- 1 Maxi-
Average .  mum . Average. l mum.
0~.0z% nitrogen _______  9 0.02 .0284. 5.7 1 8.8 8 1 11
.321—.%Z> nitrogen ______ __ 17 0.56 .0471 9.4 i 26.4 12 i 35
. 41-. no nitrogen ______ _- 27 0.63 .0681 ~ 13.6 i 31.7 18 42
.(l(51—.08% nitrogen ______ __ 13 - 0.78 .1207 24.1 i 74.0 32 i 98
.081-.10% nitrogen ______ -_; 12 0.81 .0995 19.9 i 18.0 20 ' 04
.101~-—.1'2% nitrogen _»_ ____ __f 5 0.57 .0991 19.8 ; 33.0 26 44
.121--.14 nitrogen _______ _; f) 0.85 .1404 28.1 j 64.0 37 i 85
.141——.1G% nitrogen ______ ___ 7 0.81 .1183 23.7 g 45.3 81 ' 00
.161—.l8‘7 Iiitrogen ______ __i I’ 1.08 .2145 42.9 55.0 56 7"
.181—.20‘7Z nitrogen ______ __j 1 1.39 .4170 83.4 ? ________ __v _______________ "i-
.201—~.2:2‘7 nitrogen ______ __1 0 ____________________________ __ ___§
.'l'_7.l-—~lll) ‘ti nitrogen _____ __| 2 1 17 29.95 59 9 I ________ __
l
Total ................ “i 105 ; 

RELATFION TO NITROGEN IN CROPS“

The relation of the total nitrogen of the soil to the average per-
centage of nitrogen in the crops, and to the quantity removed from
the soil, is shown in Table 3, and graphically in Figure 3.

The HVQPHQG nitrogen content of the crops increases with the average

nitrogen content of the soil. It would have been better, however. had

__7__

a larger number of crops in each group been subjected to analysis.
Work along this line is being continued.

The average nitrogen removed from the soil increases with the
average nitrogen content of the soil, though somewhat unequally.

The nitrogen removed from the soil ha.s also been calculatedto
bushels of corn per acre. It is assumed that a bushel of corn requires
1.5 lbs. nitrogen for grain, leaves and stalk, and that the plant can
draw upon the soil to the depth of about 8 inches, such depth of soil
weighingtwo million pounds per acre. i _

50

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0 .02 .04 .005 .08 ./0 J2 ._/4i ./6 ./8
' fifiii/[Rfi/VMGKS Of/Wffiflif/V/WJO/l.

Fig. 3.-——Relation of the amount of nitrogen removed by the crop to the nitrogen
content of the soil.

The nitrogen withdrawn by the crops in the pot experiments, ex-
pressed as bushels of corn, increases from 8 bushels per acre for soils
containing less than {O2 per cent. nitrogen, to 56 bushels per acre for
soils containing O.16—O.18 per cent. nitrogen. The maximum corn
possibility is more irregular than the average. These calculations do
not take into consideration the nitrogen in the roots of the plants, or

. that contained in the seed planted in the pots.

RELATIVE DEFICIENCY.

We must here emphasize the fact brought out in Bulletin 145, that
deficiency is ‘rtrlative, and that the composition of the soil and the re-
sults oi’ the pot experiments must be considered in connection with the
kncnvii tie] d possibilities of the soil. If the nitrogen is not sufficient for
the maximum crop possible under the soil, condition, then the soil will
appear deficient, but even small quantities of nitrogen may be suflicient
for soils located under relatively unfavorable conditions. This matter
will be discussed in detail in future bulletins, when application is made
c>f the results of the work on the active phosphoric acid, active potash,

  and total nitrogen of the soil.

ACKNOWLEDGMENT.

Assistance in the analytical and other work involved in the prepara-
tion of this bulletin has been rendered by Messrs. Rather, Asbury, Kelly,
Cgier, Carlyle, Herron and possibly other assistant chemists.

.__g.__

TABLE L-Group 1. 0——.02%, TOTAL NITROGEN.

Percent- Grams
Name of Weight of crop, age of nitrogen Year. Defl-
Labora- Name of soil. crop. grams. nitrogen in ciency.
tory N0. in PK crop.
PK PNK crop.
819 Norfolk fine sandy loam Corn 4.8 18.2 0.66 0.0317 1907 DD
Wheat 2.5 1.9 1908 S
Corn 2.9 21.1 0.43 .025 1908 DD
821 Orange fine sand ______ _- Corn 2.6 10.8 1907 DD
Corn 0.4 5.0 1907 DD
Corn 2.9 7.2 0.45 .0130 1908 DD
Mustard 1.0 1.5 1908 D
828 Norfolk fine sand _____ -_ Corn 3.6 19.2 0.98 .0353 1907 DD
859 Norfolk fine sa:-;d _____ -- Corn 6.7 29.8 0.62 .0415 1908 DD
860 Orangeburg fine sand--- Corn 5.8 36.1 0.69 .0400 1907 DD
Corn 0.4 2.5 ~ 1908 DD
2350 Susq. fine sandy loam“ Mustard  2.9 I 1909 S
Corn 7 . O 48.0 0. 55 .0385 1910 DD
3654 Orangeburg fine sand--- June
corn 5.0 22.5 0.62 .0310 1910 DD
3655 Orangeburg fine sand June
S. S. ________________ __ corn 2.2 29.5 0.56 .0123 1910 DD
Average (15) _______ -- 3.39 17.08
Average (9) ________ __ 0.62 l .0284
I
TABLE 4.-—Group 2. 0.02—.04, TOTAL NITROGEN.
Percent- Grams ,
Name of Weight of crop, age of nitrogen Year. Defi-
Labora- Name of soil. crop. grams. nitrogen in eiency.
tory No. - ' in PK crop.
PK PNK crop.
172 Norfolk sand ......... __ Corn 7.2 9.7 _ 1906 D
Cow peas 7.5 10.2 __________________ __ 1906 D
Oats 5.0 6.0 __________________ __ 1906 D
310 Orangeburg ‘fine sandy
loam ________________ __ Corn 5.4 6.1 __________________ __ 1906 D
Cow peas 4.1 4.0 _ 1906 S
Oats 4.1 5.0 _ -__ 1906 D
316 Norfolk fine sandy loam Corn 6.9 12.1 1906 D
Cow peas 5.3 7.7 __________________ __ 1906 D
Oats 4.5 7.0 _ 1906 D
318 Lufkin fine sand _______ _- Corn 3.2 4.9 1906 D
Cow peas 2.0 2.6 1906 D
a Oats 5.9 6.9 1906 D
820 Susq. fine sandy loam“ Corn 5.6 12.5 __________________ -- 1907 DD
822 Lufkin fine sandy loam_ Corn 21.0 20.6 1907 0_g%lkin
u .
911 Norfolk fine sand _____ __ Grass 1.4 2.5 _ 1908 D
913 Susq. fine sandy 1oam__ Corn 6.0 6.4 . ________ __! ________ __ 1907 S
936 Barton sandy loam"--- Corn ' ' 1907
Wheat 0.7 1.6 1908 DD
Corn 4 .8 11.3 __________________ _ _ 1908 DD
Sorghum 8.5 12.7 _________________ _- 1909 D
937 Orangeburg fine sandy
am _________________ __ Corn 6.4 8.4 1907 D
1120 Susq. fine sand S.S.____ Corn 4.0 13.0 .62 .0248 1908 DD
Mustard 4.9 5.1 __________________ _- 1908 S
Sorghum 8 . 5 27 .3 ___________________ - - 1909 DD
1125 Winfield fine sand _____ -_ Corn 13.9 32.0 1908 DD
Mustard 1.2 3.5 __________________ __ 1909 DD
Sorghum 5.9 29.8 - 1909 DD
1126 Winfield fine sand S. S._ C-orn 11.0 26.2 0.50 .055 1908 DD
Sorghum 4.8 ~ 1.7.5 __________________ _- 1909 DD
1130 Lufkin silt loam S.S._-_ Corn 16.6 29.0 0.59 .0979 1908 Di
1134 Norfolk fine sand S.S.__ Corn 9.6 29.4 0.50 0480 1908 DD
Mustard 1.0 6 .6 __________________ _ - 1908 DD
1.136 Norfolk fine sandy loam
S_ , __________________ __ Corn 7.2 23.0 __________________ __ 1908 DD
1200 Nueces fine sand _______ -_ Corn 5.0 16.0 0.53 .026 1908 DD
Mustard 2.1 7.4 __________________ __ 1908 DD
1207 Nueces fine sandy loam Corn 20.0 26.0 0.66 | 1 1320 1908 D
Mustard 1.6 6.4 ________ __| ________ __ 1909 DD
Sorghum 17 .9 16 .6 ________ "i ________ _ _ 1909 S
1577 San Antonio clay loam_ Mustard 9.7 11.9 --------- -. -------- _- 190B D
Sorghum __15.9 15.7 ________ __l ________ _- 1909 S
Kaffir 2.9 4.1. ........ _-' ........ __ 1909 D
1579 Norfolk silt loam ______ -- Mustard 8.8 10.2 ________ __' ________ __ 1908 D

___9__

 

HFABLIG 4.-—Group L-montinued.
i l
- I Percent- F Grams
A ; _ Name of Weight of croix. age of f nitrogen Year. - Deli-
Labora- Name of soil. crop. grams. 7 nitrogen. in I ciency,
1301‘? No.1 ——-—-— ; in PK crop. 3
l PK  PNK  crop.
_ ; Corn 10.4 i 21.3 5 __________________ __ 1909 D1)
1585 "Willis sand S.S ________ __ Mustard 5.1 9.7 f __________________ __ 1903 1)
Sorghum 8. 2 17 . 8 i 1909 DD
1586 San Jaeinto clay ______ __ Mustard 5.9 10.2 i __________________ __ 1903 1)
1588 Lufkin sandy loam ____ -_ Mustard 4.9 8.7 i 1908 D
1589 Lufkin sandy loam ____ __ Mustard 1.2 5.1 1 1908 DD
1590 Deep S.S. to 1588 ...... __ Mustard .05 4.2 ‘ __________________ __ 1903 D1)
1591 Lufkin sand __________ __ Mustard 4.3 7.5 * ‘ 1903 I)
1592 Lufkin sand S. S ______ __ Mustard 2.0 6.9 } 1908 DD
1596 Austin clay S.S ________ __ Mustard 2.9 4.0 l 1903 D
1598 Yazoo sandy loam S.S..- Mustard 3.3 9.0 ________ -1 ________ _- 1908 DD
2347 Susq. gravelly loam S.S. Mustard 2.3 3.0 ________ __F ________ __ 1909 D
Oorn 10.0 25.2 0 49 i .049 1910 DD
2348 Norfolk fine sandy 10am Mustard 1.6 l 2.3 ________ -1 ________ __ 1909 D
Oorn 12.0 i 33.0 0.49 0588 1910 DD
2351 Susq. fine sandy loam Oorn 0r i
oats 8.5 i 15.0 0.63 .0535 1910 D
Mustard 2.2 i 3.9 ___________________ __ 1910 D
2352 Norfolk fine sand ______ __ Mustard 3.5 T 6.8 __________________ __ 1910 D
Oorn 8.0 36.5 0.58 i 0466 1910 DD
Mustard 0.8 0.8 ________ __‘ ________ __ 1910 S
Oorn 11.8 36.6 g ________ __‘ ________ __ 1911 DD
2353 Norfolk fine sand S. S.-- Mustard 1.9 1.6 i ___________________ __ 1909 D
Oorn 3.7 26.6 _______-__. ________ __ 1910 DD
Sorghum 3 .2 29.4 0. 55 .0176 19] 0 DD
3331 Travis gravel _________ -- Sorghum 10.7 50.4 0.43 0460 1910 DD
Mustard 2.0 5.5 ‘ 1910 DD
Oorn 5.4 50.8 ! 0.48 .0259 1911 g DD
3346 Susq. fine sandy 1oam__- Sorghum 6.6 40.5 ' 0.52 .0341 1910 ; DD
3975 Lutkin fine sandy loam §
S. S. to 3974 ________ __ Oats 3.0 11.2 1910 1 DD
3976 Lufkin clay ___________ __ Oats 8.1 13.0 5 ' - 1910 D
1 Oorn 4.2 31.8 0.56 .0235 1911 DD
4644 Poor upland __________ __ Oorn 19.2 47.7 1911 I DD
3656 Orangeburg fine sandy June
10am ________________ __ corn 6.2 20.4 0.67 .0415 1910 DD
3657 Orangeburg fine sandy June
~ loam S.S ___________ -_ corn 3.0. 17.9 0.66 .0198 1910 DD
Average 0.19 13.35 l-
Average (17) 1 0.56 .0471 ______ --
TABLE 4.-—Group S. 0.041—-.06 TOTAL NITROGEN.
i Percent-l Grams ?
_ Name of ;Weight of crop, age of nitrogen Year.  Defi-
Labora- Name of soil. crop. ' grams. nitrogen in , cieney.
tory No. - in PK crop.
PK PNK crop. ,
314 Norfolk fine sand ______ -_ Oorn 11.9 10.7 __________________ __ 1906 S
Oow peas 6.5 9.4 __________________ __ 1906 D
Oats 5.8 4.5 __________________ __ 1906 D
340 Susq. sandy loam ..... -_ Oorn 7.0 12.0 ___________________ __ 1906 D
' Oats 3.0 4.0 ___________________ __ 1906 D
Mustard 1.0 0.1 ___________________ _. 1908 S
Sorghum 1.6 1.1 __________________ -1 1909 S
342 Orangeburg fine sand___- Oorn 1.8 2.0 -__-______ _______-__5 1906 S
Oats 12.0 10.5 ___________________ __;I 1907 S
844 Orangeburg fine sandy . I
loam .................. -- oats 3.0 4.0 ......... .4 ________ __| 1900 s
816 Laredo fine sand ______ __ Oorn 13.0 16.2 1.04 ‘ .1352 ' 1907 D
Oorn 4 .0 3.4 1.63 .0424 1907 S
Grass g 2.8 6. __________________ __ 19,08 D
Mustard 0.5 10.8 .................. >01‘ 190s n
827 Laredo silt loam ...... __ Oorn 9.8 15.5 _; 0.71 .0695 i 1907 D
Oorn 2.2 2.9 g __________________ -_; 1907 D
Grass 2.9 3.5 i __________________ __| 1908 I D
Mustard 7.8 7.5 ' .................. --! 190s ; s
Sorghum 8.1 13.3 .................. J 1909 ~; n
s50 Susq. sandy loam ..... -_ Oorn 2.2 1s.0 0.74 010-2 I 190s i no
914 Lufkin fine sandy loam_ Oorn 4.4 1.0.9 __________________ -_ 1907 l DD
Grass 3.1 3.8 1 __________________ __ 1908 1 D
970 Surface soil ........... -_ Mustard g 2.0 1.0 i .................. -- 190s § DD
1119 Susq. fine sand _______ -_ Oorn = 5.5 35.6 -_-__ ___- ________ -_ 1908 l DD

__1Q__

'l‘A1f§1.1£ 4.—-Ciroup :3—-vonti11ued.

 
 

I

Percent- Grams

' Name of Weight of crop, age of nitrogen Year. Defi~
Labora- Name of soil. é crop. grams. nitrogen in a ciency.
tory N0. —————— in PK 1 crop.

PK PNK crop. 1
Mustard 5.2 6.9 ________ __1 ________ __ 1908 1)
Sorghum 7.6 25.95 ________ __1 ________ __ 1909 DD
1124 Winfield fine sand 1oan1 1
S-S- ----------------- _- Corn 23-7 21.0 0.54  .1279 190810 s
Mustard 5.1 4.6 _________ -1 ________ __ 1908
1129 Lufkin silt 10am ______ __ Corn 25.8 36.5  0.51 1 .1472 1908 1S9
1133 Norfolk fine sand _____ __ Corn 12.0 15.9 0.59 1 .0708 1908 D
__ Mustard 2.0 5.0 I ________ __I ________ __ 1908 D1)
- Sorghum 5.9 26.0 _________ _! ________ __ 1909 DD
1138 Susq. fine sandy loam
S. S. ________________ __ Corn 12.0 20.2 0,62 .0744 190g D
Sorghum 6 . 6 18. 5 __________________ _ _ 1909 D1)
1139 Lufkin fine sandy loam- Corn 23.1 44.0 0.53 .1246 1908 D
Mustard 4.4 4.4 I __________________ __ 1909 S .
Sorghum 10.5 28.3 ________ __ ____.______ 1909 D1)
1140 Iufkin fine sandy loam Corn 21,0 45,5 ___________________ __ 1903 DD
1203 Houston clay S.S _____ __ Corn 22.0 29.7 0.74 1584 1908 D
lVIustard 4.0 6.8 ___________________ __ 1909 D
1205 Houston loam S.S ____ __ Corn 7.0 16.0 0.84 0588 1908 DD
Mustard 6.5 10.2 __________________ __ 1909 D.
1206 Nueces fine sandy loam- Corn 11.5 17.5 I 0.54 .0621 1908 D
1578 San Antonio clay loam
S.S. _________________ __ Mustard 5.5 9.7 __________________ __ 1908 D

1587 San Jacinto clay S.S.__ Mustard 5.0 9.3 __________________ "I 1909 D

1597 Yazoo sandy loam ____ __ Mustard 4.9 10,4 __________________ __ 1908 D1)

1926 Yazoo sandy loam ____ -_ Oorn 13.4 ' 10.8 I __________________ __1 1909 S

1334 3.8. cob1931-.fi ......... -- Corn 15.8 22.6. 1 ________  ........ n-t] 1909 D

4 range urg ne sandy 1 1
1 loam ................ __ooru 4.1 38.5 1' 0.61 1' .0244 a 1910 DD
3332 Travis gravel- ________ __ Sorghum 14.5 50.5 1 0.51 .0740 1910 DD
Mustard 4.6 2.7 1' __________________ -_ 1910 S
7 l fi Corn 21.9 46.8  ........ W’ ________ _- 1911 DD
333 Miler ne sandy 10am June
corn 11.0 24.7  0.51 1 .0627 1910 DD
3339 Crawford 10am _______ __ Sorghum 17.2 60.5- ‘ 0.43 ’ .0740 1910 DD
Mustard 1.4 4.4 t __________________ __ 1910 DD
foorn 11.3 42.0 1 0.43 0486 1911 DD
3340 Crawford loam _______ -_ Sorghum 16.5 62.6 1 0.40 0660 1910 DD
Mustard 0.5 2.4 1 ________ u] ________ __ 1910 DD
» Corn 7.4 50.3 ' 0.56 .0414 1911 DD
3345 Susq. fine sandy loamnlSorghum 17.9 55.5 1 0.48 1 .0859 1910 DD
1Mustard 0.7 1.5 1 ________ __1 ________ __ 1910 D
‘Corn 8.2 48.2 1 0.56 1 0459 1911 DD
3631 Lufkin fine sandy 1oam_ Sorghum 1.5.2 50.9 l‘ 0.42 0638 1910 DD
Mustard 2.7 4.8 , ________ u’ ________ __ 1910 D
Corn 7.5 37.2 0.55 i 0413 1911 DD
3633 Houston black c1ay_____ Sorghum 3.5 18.1 0.14 1 025-9 1910 DD
3634 Houston black clay S.S. , 1
to 3633 ______________ __ Sorghum 3.0 10.2 0.97 1 .0281 1910 DD
Mustard 3.3 4.1 ________ "1 ________ __ 1910 D
5974 Lufkin fine sandy loann Oats 6.3 12.5 ________ __1 ________ __ 1910 D
ooru 6.6 40.5 1 0.66 .0136 1911 DD
3977 Norfolk sandy loam-__.-'Oats 7.9 14.6 __________________ -_ 1910 D
Corn 4.6 27.7 0.54 0248 1911 DD -
4603 Good upland _________ __Oorn 24.2 61.6 __________________ __ _1911 DD
1 Average ........... -- 8.11 18.861 0.63 .0681 ______ --
TABLE 4.—Group 4. .061—-.08% TOTAL NITROGEN.
Percent- Grams
Name of Weight of crop, age of nitrogen Year. Defi-
Labora- Name of soil. crop. grams. nitrogen in ciency.
tory No. in PK crop.
PK PNK crop.
817 Lufkin fine sandy loam Corn 14.8 30.1 0.77 .1030 1907 DD
Corn 2.9 3.4 1.51 .0435 1907 D
Grass 1 .2 2 .9 1908 DD
818 Sanders loam _________ __ Corn 39.2 47.1 0.93 3697 1908 D
Corn 2.7 5.1 .................. __ 1908_ D
832 Orangeburg fine sandy .
' 1o am C orn 20. 26.2 1 .42 .2868 1907 D

____---__----_¢—__

TABLE 4.——Group 4—-eontinued.

 

A Percent- Grams
Name of Weight of crop, age of nitrogen Year. Defi-
Labora- Name of soil. crop. grams. nitrogen in ciency-
tory N0. - in PK crop.
PK PNK crop.
. Corn 0.7 1.4 __________________ _- 1908 D
932 Miller silt loam ........ _- Corn 4.0 6.2 __________________ __ 1907 D
Grass ' 3.3 6.7 __________________ ..- 1908 D
982 Cameron clay S. S.___- Corn 30.4 50.9 0.57 1710 1908 D
Mustard 5.1 8.1 __________________ __ 1908 D
Sorghum 22 .7 26 .5 1909 D
1123 Winfield fine sandy loam Corn 17.0 25.8 0.87 1.044 1908-09 DD
Mustard 6.8 9.6 ___ _ 1908 D
Sorghum 28 .7 33 .7 1909 D
1594 Houston black clay S. S. Mustard 4.9 11.3 __________________ __ 1908 DD
Sorghum 8.1 22.7 __________________ __ 1909 DD
1600 Houston black clay S.S. Mustard 4 6.9 11.1 __________________ __ 1908 1)
Sorghum 14 .4 27 .9 _ 1909 D
2341 Franklin clay S.S ..... -- Mustard 2.8 4.0 __________________ __ 1909 D
Corn 18.0 37.0 0.52 0936 1910 D
Sorghum 2.1 . 28.9 __________________ __ 1910 DD
2346 Susq. gravelly 1oam___-_'Gorn 25.0 45.6 0.50 .1250 1910 D
2829 Denison clay __________ _-t(T1orn 14.0 16.5 0.66 .0924 1910 D
une
corn 3.5 11.7 0.94 0329 1910 DD"
2957 S.S. t0 2956 ____________ __ Mustard 5.1 5.3 ___ ' 1909 S
Corn 7.0 28.0 0.46 .0322 1910 DD
3632 Lufkin sandy loam---" Sorghum 17.9 45.3 0.43 .0770 1910 DD‘
Mustard 0.7 2.2 __________________ -_ 1910 DD
Corn 6.1 43 .3 0. 59 0370 1.911 I DD
Average _ ' 11.04 20.81 __________________________ "1
Average (13) _________________________________ __ 0.78 1207 _______ _-!
TABLE 4.—-Group 5. 0.081.—.10% TOTAL NITROGEN.
Percent- Grams
' Name of Weight of crop, age of nitrogen Year. Defi-
Labora- Name of s_oi1. crop. grams. nitrogen in ciencyz.
tory N0. ~ . , in PK crop.
PK PNK crop. y
133 Sanders loam ________ __ Corn 9.7 11.9 __________________ __ 1906 I)
Oats 10.2 10.2 _ 1906 S
336 Susq. fine sandy loam; Oorn 7.5 20.1 1906 DD
831 Laredo silty clay ...... __ Corn 1 26.3 60.0 0.55 .1447 1907 DD
Wheat I 1.8 1,9 __________________ __ 190s s
Corn i 14.0 46.9 _ 1908 DD .
833 Laredo fine sandy 10am- Corn  21.4 29.0 1.12 23.97 1907 D
Gorn . 5.6 2.2 __________________ __ 1908 S
Grass 1 2 .8 5 .9 1908 DD"
834 Orangebrlrg fine sandy
loam ________________ _- Corn 4.1 24.6 0.93 .0372. 1908 DD
893 Lufkin clay ___________ __ Mustard 4.5 1.3 __________________ __ 1908 S‘
938 Austin fine sandy loam__ Corn 4.5 8.8 2.66 1197 1907 D
’ Wheat 3.2 3.0 __________________ __ 1908 S
Corn 15.1 40.4 0.47 .0709 1908 DD‘
Mustard 5.7 6.5 _ _ 1908 D
Sorghum 10.6 10.7 _ __________________ __ 1909 S‘
940 Wilson loam ___________ __ Corn 9.8 6.7» 1907 D
Grass 3.8 5.0 __________________ __ 1908 D
Mustard 6.1 10.1 __________________ __ 1.908 D
Sorghum 11.3 10.0 __________________ __ 1909 S‘
1202 Houston clay, probably
Victoria loam ______ __ Corn 33.0 36.3 0.51. 1683 1.908 D
1202 Houston clay, probably
Victoria loam ______ __ Corn 16.0 14.4 0.51. .0816 1908 S
Mustard 5.6 7.7 .................. __ 1.909 D
1581 Houston black clay loam
S.S. _________________ -- Mustard 5.3 9.9 __________________ ___ 1908 D
1582 Houston gravelly clay-“ Mustard 5.7 9.9 __________________ __§ 1908 D
Sorghum 14 .8 27 .0 __________________ _ -1 1909 D‘
Kaflir 3.2 16.1 .................. __; 1909 _ DD‘
1.583 Houston gravelling clay 1
S.S. ______ __.. ________ __ Mustard 3.9 7.2 ________ _-; ________ "i 1903 D
1593 Houston black c1ay_____ Mustard 6.3 12.0 ________ __; ________ __= 1908 D
1595 kustin clay ___________ -- Mustard 5.8 9.9 ________ -_. ________ __ 1908 1 D
1928 S.S. to 1927 ___________ __ Corn 18.8 7.6 ________ -1 ________ __ 1.909 S
Sorghum 7.6 23.7 ________ __= ________ u‘ 1909 l DD-
Mustard 3.8 5.7 ‘ ___________________ -. 1909 ' D’

 2___

TABLE 4.——Group

5——continued.

 

Percent-l Grams 

 

 

 

 

Name of Weight of crop, age of nitrogen Year. Defl-
Fabolréaw Name of soil. crop. 1 grams. nitrogen in ciency
orY 0. ?-— in PK crop. {
1  PK ’ PNK crop. I I
1931 Oalcasieu fine sandy ; I i l]
10am ................ _- oorn ' 30.0 20.5 -_-..--_---t___-_-____ 1909 s
S Orghum 22 . 5 32 . 9 1909 D
1934 Sharkey clay S. S.____ Corn 19.1 29.1 _________ __‘ ________ __ .1909 D
2342 Lufkin fine sandy loam_ Corn 15.0 50.0 0.53 .0795 1910 DD
L fk fi Sorghum 7.0 40.9 0.58 .0406 1910 DD
2343 u in ne sandy loam
. S. _______________ __ Corn 19.5 40.5 0.65 .1268 1910 S
2826 Sherman fine sandy loam Oorn 6.5 48.5 0.56 .0464 1910 DD
Corn 6.2 29.4 0.63 .0391 1910 DD
Average _____________________ __ 10.33 18.08
Average (12) .......  ________________ u] ______ __ 0.31 .0995 ...... _-
TABLE 4.——Group 6. 0.101-—.12% TOTAL NITROGEN.
3 r I Percent- I Grams j I
_ 1 Name 0f Weight 0f HOD»! age of nitrogen I’ Year. J Defi-
gxzbolrla- ' Name oi soil. crop. grams. I nitriajgiten in I I ciency.
OIY 0- ——-— in crop. 1
PK I PNK l? crop.  
910 Houston black c1ay-_-__ Mustard 6.2 I 8.2 l] ________ __! ________ n" 1908  1)
Sorghum 18.1 22.1 ________ __! ________ __ 1908 | D
912 Bastrop sandy loam____ Corn 5.2 4.2  ________ n! ________ __! 1907 l‘ S
, Oorn 23.5 47.7 j ________ -_; ________ -_! 1903 1 D
933 Bastrop clay . ........ __Oorn 6.3 3.1 , ________ "I ________ __f 1907 j s
Grass 4.9 5.5 s j 1908 D
Mustard 5.3 15.9 ________ __] _________  1903 n1)
Sorghum 15.4 22.5 __________________ __; 1909 D
934 Wabash clay __________ __ Corn 10.7 5.6 | f 1907 S
Grass 2.7 5.1 ________ __‘ ________ __% 1903 s
Mustard 3.1 11.7 ! 1903 no
935 Lufkin clay ........... -_ Corn 12.5 4.5 ________ u} ________ __ 1907 s
Grass 4.9 2.9 ........ __1 ________ _-f 190s‘ s
Mustard 11.7 0.1 f ________ __f ________ __1 1908 S
Sorghum 26.3 . 15.0 t ________ __{ ________ __§ 1909 S
941 Houston loam _______ -- Corn 10.7 13.2 g _________ -2 ________ __g 1907 I n
Grass 3.7 7.0 I ________ -_f ________ __I' 1908 D
- Mustard 3.7 9.7 __________________ __.1 1908 DD
‘1121 Hagensport loaru ____ __ Corn 30.0 48.7 0.55 1650  1908 D
Mustard 1.9 2.6 __________________ __; 1908 | D
Sorghum ______ __ 32.2 __________________ __! 1909 1
1122 Hagensport loam ____ __ Corn 18.0 24.3 _________- ________ __§ 1908 D
31127 Houston clay _________ __ Corn 27.8 39.3 ___________________ __! 1908 D
1580 Houston black clay loam Mustard 6.2 11.0 __________________ u! 1908 D
1599 Houston black clay"--- Mustard 4.8 13.0 __________________ __F 1908 DD
2330 Denison clay loam .... __Gorn 20.0 45.5 0.52 1140 I 1910 nn
3335 Houston black clay"--- Oats 5.5 _ _, 1910
Oorn 11.0 35.3 0.49 .0539 1911 DD
3663 Orangeburg clay ______ _- June
corn 15.4 20.2 0.69 .1063 1910 D
Mustard 1 . 0 3. 3 __________________ -- 1910 DD
Corn 9.7 47 .9) 0. 5' . 0563 1911 DD
22956 Orangeburg clay ____ __ Mustard 4.5 5.0 __________________ __ 1909 S
Corn 15.0 43.0 ___ 1910 DD
Average -- 10.96 17.98
Average (5) ________ __ ___ 0.57 .0991 ...... _-

__13__

 

TABLE 4.——Group 7. 0.121-—.14% TOTAL NITROGEN.
Percent- Grams
Name of Weight of crop, age of nitrogen Year. Defi-
Labora- Name oi soil. crop. grams. nitrogen in ciency.
$01‘? NO- in PK crop.
PK l PNK crop.
s24 Houston black clay"--- Oorn 10.2 i 16.1 i l 190s n
Oats 10.0 2.6 i 1907 s
338 Wabash clay ________ _____ Oorn 7.0 12.0 I 1906 D
Oats 6.0 5.9 1907 S
829 Houston loam ________ __ Oorn 23.8 31.4 .80 .1906 1907 D
Oorn 4.0 5.0 1.34 .0536 1907 D
. Grass 2 . 9 7 .2 1908 DD
830 Laredo gravelly 10am-" Oorn 17.2 5.0 1.86 .3199 1908 S
939 Houston black clay _--- Oorn 5.2 6.5 __ 1907 D
Grass 3.3 3,3 1908 S
Mustard 7 .2 13 . 2 . 1908 D
Sorghum 19.1 28.4 i 1909 D
2410 Subsoil t0 2409 _________ __ Mustard 1.1 4.2 1 1909 DD
Oorn 31 . 5 36 .0 .83 2615 1910 D
2831 Denison clay loam ..... -_ Mustard 2.2 2.8 __________________ _- 1909 D
Oorn 15.0 42.0 .48 .072 1910 DD
2944 Houston black clay loam Oorn 13.0 43.0 .51 .0663 1910 DD
Sorghum 8.0 44.7 .57 .0456 1910 DD
3662 Orangeburg clay ______ -_ June
corn 31.3 24.5 .74 .1576 1910 D
Mustard 1.7 5.1 ________ __ 1910 DD
Oorn 12 .8 49 . 3 . 52 . 0966 1911 DD
Average 11.08 18.29 -_ ...... --
Average (9) \ .85 1404 i ______ _-
TABLE 4.—Group 8. 0.141—.16»% TOTAL NITROGEN.
Percent- Grams
Name of Weight of crop, age of nitrogen Year. Defi-
Labora- Name of soil. crop. grams. nitrogen in ciency.
tory No. _ in PK crop. i
PK PNK crop. i
1925 Yazoo sandy 10am ..... -_ Oorn 32.6 43.8 ________ __l _________ _. 1909 D
2340 Franklin clay _________ -_ Mustard 3.0 1.5 1909 S
Oorn 23 . 5 41 . 5 . 57 . 1340 1910 D
Sorghum 10.7 44.7 .61 .0653 1910 DD
2828 Denison clay ........... _- ‘(Tlorn 28.7 25.5 .79 .2267 1910 S
une
corn 7 . 3 16 . 2 . 72 . 0526 1910 DD"
- Mustard 1 . 7 4 .8 1910 DD
2948 Houston clay _________ -_ Oorn 13.5 10.0 1.63 .2200 1910 S
3341 Yazoo clay ____________ __ Oats 8.4 13.2 1910‘ D
O orn 15 . 0 38 .0 . 54 . 0810 1911 DD
3343 Crawford clay ________ __ Oats 9.0 19.8 1910 DD
Corn 6.1 38.7 .80 0488 1911 DD
Average 14.12 24.8 '
Average (7) .81 .1183 _______ _.
TABLE 4.—Group 9. 0.161—-.18% TOTAL NITROGEN.
Percent- Grams |
Name of Weight of crop, age of nitrogen‘ Year. Defi-
Labora- Name oi soil. crop. grams. nitrogen in ciency.
tory No. in PK crop. 1
PK PNK crop. 
334 Houston loam ........ _- Oorn 16.0 30.1 = i 1906 D
Oats ' 7.5 8.5 3;- 1907 D
843 Wabash clay _________ -- Oorn 19.0 16.1 1.44 ; _2746 1907 1)
Wheat 3.1 3 7 ........ -1 ________ __ 1908 S
Oorn 20.0 46.1 .43 I .0860 190s DD
Mustard 2 .7 2 .6  1908 S
851 Wilson clay 10am _____ -- Oorn 20.8 23.4 1.36 I 2829 1907 D
Grass 4.2 4.5 1908 S
Average 11.66 16.87 _-_
Average (3) ________________ __ 1.08 .2145 ______ __

___]_&__..

TABLE 4. Group 1o. 0.1s1-.20% TOTAL NITROGEN.

I
I Percent- Grams
Name of Weight of crop, age of nitrogen Year. ' Defl-
Labora- i Name of soil. crop. grams. nitrogen in ciency.
tOFY No. in PK crop.
_ PK PN K ' crop.

330 ‘Crawford stony c1ay___- Corn 10.1 19.8 _ 1906 D
Oats 6.5 6.9 1907 D

845 Sanders silt ___________ __ Corn 30.0 29_2 1,39 ,4170 1903 s
Corn 8.2 8.0 1908 S

Grass 4.6 9.9 _ 1908 D

1929 Yazoo clay ............ __ Oorn 15.3 32.9 1909 DD
2822 Sherman 10am ________ __ Mustard 1.5 2.4 1909 D
Corn 37.5 41.0 1910 D
Average - __ 14.2 18.75
Average (1) 1.39 .4170 . ______ __

TABLE 11.-Group 11. 0.201——.22% ‘TOTAL NITROGEN.

Per_cent- Grams -
Name of Weight of crop, age of nitrogen Year. Defl-
Labora- Name of soil. crop. grams. nitrogen in  ciency.
tory N0. -—————————~— inPK crop.
PK | PNK crop. I
1927 “Corn I 36.25 l 30.25 I 1909 s

TABLE 4.—Group 12. O.221——UP % TOTAL NITROGEN.

- Percent- Grams
Name of Weight of crop, age oi nitrogen Year. Defi-
Labora- Name of soil. crop. grams. nitrogen in ciency.
tory No. _ in PK crop.
' PK PNK crop.

1930 Yazoo clay subsoil _____ _- Corn 5.0 8.1 1909 D

Sorghum 10. 7 29 .4 1909 DD
1133 Sharkey clay __________ __ Corn 18.7 14.8 1909 S
1935 Houston black clay ____ __ Corn 20.3 27.6 1909 D
1936 Houston black clay .... __ Corn 26.4 32.1 1909 D
2946 Houston black clay ____ __ Gorn 23.1 24.1 1.65 .3813 1910 S
1131 Wabash clay _________ __ Corn 32.0 47.8 .68 .2176 1908 D

Mustard 6.5 13.2 1908 D

" Average _ 17.84 24.64
Average (2) ___ _ 1.17 .2995 ...... __

SUMMARY AND CONCLUSIONS.

1.. This bulletin‘ contains the results of 332 pot experiments, to test
the needs of soils for nitrogen. ‘

2. t There is a relation between the number of crops deficient in ni-_

trogen in pot experiments, and the total nitrogen of the soil.

3. The Weight of the crops increases with the nitrogen content of
the soil up to .06 per cent., and remains nearly the 'same for the groups
of soils containing .06-0.18 per cent. nitrogen.

4. The effect of fertilizer nitrogen in the pot experiments decreases
as the percentage of nitrogen in the soil increases.

f’ I

o. The average nitrogen content of the crops increases as the
nitrogen content of the soil increases, but a larger number of crops
should be studied With respect to this point. '

6. The average nitrogen Withdrawn by the crops in the pot experi-

ments, expressed as bushels of corn per acre, increases from 8 bushels

__15__

for soils containing lessthan .02 per cent. nitrogen, to 56 bushels for.

soils containing O.16——O.18 per cent. nitrogen.
7. It is difiicult to establish percentages below which a soil is “de-

ficient,” and above Which it is not, but the possibility of production r

can be related to the quantity of plant food in the soil, and other factors
of production.