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Yields, Growth, and Management
Requirements of Selected Crops
as Influenced by Soil Properties

The Texas Agricultural Experiment Station - J. E. Miller, Director -College Station, Texas - The Texas A&M University System

CONTENTS

SUMMARY 2
INTRODUCTION 3
EXPERIMENTAL PROCEDURES 3

Cotton 3

Grain Sorghum 4
Tomatoes 5
Sugarcane 5

Sweet Sorghum 5

SUMMARY

The role and importance of soil properties on adaptability,
management requirements, and performance of different crops
have been frequently cited in the literature. However, research
data on adaptability and management requirements as influ-
enced by soil properties have rarely been presented. This pub-
lication is a summary of about 2O years of field research study-
ing the requirements of different crops on soils with markedly
different physical and chemical properties.

Under normal rainfall on fertile medium-textured soils
many crops in South Texas can be grown with no irrigation, or
with one irrigation applied during the critical demand period.
Extensive root growth allows the plants to exploit a deep reser-
voir of available water. Frequently rainfall supplies available
water before the effective root zone is in need of replenish-
ment. Studies using drainage lysimeters have shown that dur-
ing dry years about l O percent of the water used by crops came
from water tables, which are often 4 to 7 feet deep on these
soils. The development of a deep root system and use of water
from water tables by annual crops can reduce irrigation needs
on medium-textured soils.

On soils such as the Harlingen and Mercedes clays, crops
require greater management and need more frequent irrigations
to maintain adequate levels of available moisture in the effec-
tive root zone. Restricted root growth because of mechanical
and/or chemical impedance means the growing plants exploit
a shallow reservoir of available water which must be re-
plenished frequently during periods of inadequate rainfall.

The Mercedes and Harlingen clay soils, under proper
management, are excellent cotton soils. Recent studies with
early maturing cotton types have shown that three irrigations
can produce yields of 11/2 to 2 bales of cotton in 130 to 140
days under adverse conditions. Cotton root-rot incidence is
rarely in evidence; therefore, losses due to this crop disease on
these soils are negligible. In contrast, timely rainfall and a deep
reservoir of available water on fertile, medium-textured soils
often supply the moisture requirements of cotton. In fact, irriga-
tion and excessive rainfall on these soils tend to produce rank

2

RESULTS AND DISCUSSION 6

Cotton 6

Grain Sorghum 12 q
Tomatoes 13
Sugarcane 14

Sweet Sorghum ‘I8
ACKNOWLEDGMENT 
LITERATURE CITED 

    
 
  
  
 
  
 
 
  
  
 
  
  
  
  
  
  
  
 
  
 
   
   
 
 
  

cotton, which often means significant yield reduct:
ing early maturing cotton such as Tamcot SP-37 a i
crop induces stress which reduces vegetative growt 
duces better fruiting and yields. Cotton root-rot can‘
nificant yield reductions on these soils. 

Tomatoes on vertisol type soils, unlike r:
very poor yields. In the spring, pear type tomatv
soils have high incidence of blossom-end rot. H‘
matoes on medium-textured soils under proper 
produce high yields with low incidence of blosso‘

Crops such as grain sorghum, sweet sorghum;
cane can be produced on medium- and fine-te a
However, the water management requirements art
influenced by soil properties. As pointed out ear »
clay soils require frequent light irrigations. Because__
permeability, the salinity hazards on soils such I
and Mercedes clay soils are considerably greater}
ally, additional water must be added to keep salt a 
as low as possible in the effective root zone. This
important for crops like sugarcane which have a1
and irrigation management requirement. On l
drained, medium-textured soils and sometimes ef’
soils rainfall is sufficient to leach salts below the 
zones. Grain sorghum and sweet sorghum 0 '
textured soils often produce as much without irri 
irrigation. Timely rainfall and a deep available w 
on these soils often supply the needs of these cro
during dry years, a timely irrigation at the preboot it
usually supplies the water need of these crops. g

Soil physical properties such as compaction i Q
surface soil can significantly alter the manage l’
ments of crops grown on these fields. Removal of
often exposes a less fertile clay or clay loam su i;
production. Soils with these type surfaces or com ‘
require more frequent light irrigations and 1-,
management. I '5

 

‘elds, Growth, and Management
equirements of Selected Crops

 Influenced by Soil Properties

C. /. Gerard, B. W. Hipp and S. A. Reeves*

The effect of soil properties on performance 0f many crops
has been frequently cited. Despite these citations little has
been written describing the actual performance of crops on
different soils. Maletic and Hutchings (17) stated that irrigation
induces changes in physical, chemical, and biological soil
characteristics which are interrelated and complex. They
pointed out that land selected for irrigation should be perma-
nently productive under the anticipated changes in physical
regime under irrigation. Danielson (6) emphasized high use
efficiency of irrigation water by minimizing water penetration
below the root zone. He further emphasized that knowledge of
rooting depth is important in designing irrigation systems, and
Kramer, Biddulph, and Nakayama (16) stated that the most
important feature of annual crop root systems is their rapid
extension into previously unoccupied soil. It is this continuous
invasion of new soil masses that enables plants to grow for
days or weeks without rain or irrigation. Numerous researchers
have emphasized the importance of soil texture and structure,
available water, and salinity on water absorption and root
growth. There are many generalizations and theoretical dis-
cussions in the literature of the effect of soil properties on plant
growth. However, many of these discussions overgeneralize
and present little or no field data demonstrating the signifi-
cance of soil properties on performance and management of
different crops. lt is the purpose of this publication to present
and discuss data describing the role and significance of soil
properties in the production of several crops.

EXPERIMENTAL PROCEDURES

Cotton

The influences of moisture regimes on yields of cotton
grown on medium-textured, moderately permeable Willacy
and Hidalgo soils were studied in 1949-50, 1955-57, 1959,
and 1961-63 (9). Treatments on Willacy loam soil are de-
scribed in Table 1. Cotton irrigation studies described in Table
2 were also conducted on Harlingen clay, a fine-textured soil,
in 1960, 1961, and 1964 (7, 8). Physical properties of the two

*Respectively, professor, The Texas Agricultural Experiment Station,
Vernon; and associate professors, The Texas Agricultural Experiment
Station, Weslaco.

 
 

TABLE 1. DESCRIPTION OF MOISTURE LEVEL TREATMENTS
FOR COTTON GROWN ON WILLACY LOAM SOIL

Moisture
level Description of treatments
A Irrigated when the water content of top 2 feet

of soil approached 65 percent of available water
before bloom stage; no irrigation thereafter.

B Irrigated when water content of top 2 feet of
soil approached 35 percent of the available
water before bloom stage; during bloom irri-
gated when the water content of top 2 feet ap-
proached 65 percent of available water until
most of the bottom bolls were mature.

C Irrigated when the water content of top 2 feet
of soil approached 35 percent of the available
water until the bottom bolls were mature. After
this, until % of the bolls were mature, irrigated
when the water content of the top 2 feet of
soil approached 65 percent of available water.

D Irrigated throughout the season when the water
content of top 2 feet of soil approached 20 per-
cent of available water.

soils are indicated in Table 3. Studies concerning the responses
of early and late maturing cotton varieties to moisture levels
were conducted from 1972 to 1974 on Harlingen clay at Pro-
greso (7, 11) and on Willacy loam soils at Weslaco in 1975.

The medium-textured soils are moderately to well-drained
deep sandy loam, sandy clay loam, or clay loam soils which
hold a good reserve of soil moisture. The sand content of these
soils decreases with depth from 7O percent in the surface foot
to about 4O percent in the fifth foot; the clay content increases
from 15 percent in the surface foot to about 3O percent in the
fifth foot.

The fine-textured soils exhibit high swelling and shrink-
age, severe cracking when dry, and very poor surface and
internal drainage. The sand, silt, and clay contents are rela-
tively constant to a depth of 5 feet.

Moisture regimes were based on available water in the top
2 feet of soil. Soil moisture at different depths was determined
using the neutron scattering technique. The experimental de-
signs were randomized block or Latin square designs.

Grain Sorghum

Irrigation-plant population experiments on grain sorghum
were conducted on Harlingen clay soils near Progreso, Texas,
in 1968 and 1969. The soil was uniformly treated with 100
pounds of P205 per acre in 1968 and 1969. DeKalb F-64 grain
sorghum was planted at rates of 125,000 and 250,000 plants
per acre on single and double rows on top of 38-inch beds,
respectively. In 1968 and 1969, planting dates for these exper-
iments were April 4 and April 24, respectively. Moisture level
treatments were in a Latin square design. Water was metered
onto plots, and moisture use was estimated by the neutron
scattering technique. The influence of planting date on yields
was investigated in 1969.

ln 1970 near Progreso, the influence of plant population
on Harlingen clay soil was investigated. Grain sorghum variety
DeKalb F-64 was planted April 23, 1970. Single- and double-
row plantings at 100,000 and 200,000 plants per acre were
compared. In addition, the influences of 90,000 to 450,000

4

 
    
 
 
  
  
 
   
   
  
  
   
  
   
 
 
   
  
   
   
 
  
 
 
   
 
  
  
  

TABLE 2. DESCRIPTION OF MOISTURE LEVEL TREA!

FOR COTTON ON HARLINGEN CLAY SOIL‘ g,“
Treatment Description
A No water was applied after first blo _
B Irrigation brought the surface 5 feet.

field capacity when the average moi *
tent of top 2 feet apptoached 75-50 =
of the available moisture. “g

C Irrigation brought the surface 5 feet’
field capacity when the average moi
tent of the surface 2 feet approached 
cent of the available moisture.

D Irrigation brought the surface 5 fee
field capacity when the average 
tent of surface 2 feet approached 25-03
of available moisture. l

1Cotton on all treatments received a preplanting irrigation. f.

2Field capacity is approximately 4.75 inches per foot; ‘l’
phere tension is approximately 3.25 inches per foot. 
centages were used in 1960. Second percentages were u l
and 1964.

'1

TABLE 3. PHYSICAL PROPERTIES OF MEDlUM- 
TEXTURED so|1.s .

Willacy fine sandy loam H 

Bulk density, g/cc 1 4 to 1 6
Sand, percent 60
Silt, percent 20
Clay, percent 20
Available water, in/ft 1 5 to 2.0
Infiltration rate, in/hr >2.0

plants per acre on yields were evaluated on doubl ,
ings. These experiments were in randomized bloc .

On March 22, 1973, and April 1, 1974, att 
ricultural Experiment Station at Weslaco, Oro-T i.
planted on Willacy loam soil at rates of about”
100,000 plants per acre in single 40-inch rows. 
lysimeters, large metal boxes (60 inches by 80 in
inches deep) holding undisturbed soil, were buri v
below the soil surface to permit cultivation, plant“
mal field operations. Suction cups at the bottom if‘-
were used to extract and maintain normal soil mo;
tions at a soil depth of 5 feet. Lysimeter installatii
fully described in previous publications (5, 10). ,1
was furrow-irrigated using a water meter and alu v
pipe. l 

ln 1974, sorghum was drip-irrigated to Suppl‘
and 150 percent of sunken pan evaporation. T?
evaporation was evaluated daily at an officii‘
Weather Service Station about 500 yards from t 
tal site. Sunken pan evaporation is about 60 y
Standard Class A pan evaporation. Drip irrigatio
applied under pressure using Submatic emitters "l
ghum were determined in each lysimeter and"
treated areas of sorghum adjacent to the lysimet

B

l matoes

Irrigation spacing experiments with different types of to-
 toes were conducted on Willacy fine sandy loam soils from
‘59-64 (12). Irrigation spacing studies with Chico tomatoes
I e conducted on this soil in 1962, 1963, and 1964. This

rt will be restricted to these particular years. Additional
i Its were previously discussed (12, 13). Experiments were in
_domized block designs. Yields and blossom-end rot of pear
l atoes were evaluated.

The influences of moisture levels and other factors on

uction of pear tomatoes were conducted on Harlingen

y soils from 1965 to 1969. Experimental designs for these
estigations were in randomized block or Latin square de-
ns. Yields and extent of yield loss as a result of blossom-end
of pear tomatoes were determined.

l garcane

During 1972, 1973, and 1974, a furrow and drip irrigation
riment was conducted on Mercedes clay loam to clay soil

I ated about 3 miles northeast of Weslaco on the May farm.
_ e soil at this site is variable, holding an average of 3.7 inches

available moisture in the top 2 feet of soil. The Mercedes
, y loam is less permeable than the lighter-textured Willacy

g d Hidlago soils but more permeable than Harlingen clay

I il. The more permeable part of the experimental site is a

ium-textured soil, especially at lower soil depths. The less

j_ rmeable part of the site is a fine-textured soil to depth of 5

t. Properties as influenced by location are shown in Table 4.
All plots of cane were irrigated after planting in November

971 and after cutting of plant cane and ratoon cane crops in

ABLE 4. SOIL PROPERTY EVALUATIONS AT SITE OF THE
GARCANE IRRIGATION STUDIES, LOWER RIO GRANDE

ALLEY OF TEXAS

. 1973 1974
iSoil depth, Density, Ks‘ Ksl Salinity
‘ in gm/cc cm/hr cm/hr mmhos/cm
l High permeability
0-6 1.39 0.29 0.17 1.4
  6-12 1.51 0.04 4.27 1.2
 12-24 1.34 10.45 6.27 1.2
§ 24-36 1 .46 3.63 3.22 1 .1
g, 36-48 1.45 2.73 3.27 1.0
i 48-60 1 .76
Moderate permeability
0-6 1 .34 2.54 1 .2
6-12 1.33 1.23 1.4
. 2-24 1 .45 3.34 1.3
‘*-  4-36 1.47 0.30 1.7
36-48 1.50 0.67 1.2
y 48-60 3.43
 Low permeability
 0e 1.31 0.04 1.10 1.4
 12-24 1.33 0.10 6.65 1.4
 24-36 1 .43 0.51 5.98 1 .9
 36-48 1 .46 0.66 0.24 3.8
48-60 1 .51 0.04 0.03 6.1
0.02

b‘

lSaturated hydraulic conductivity.

November 1972 and January 1974, respectively. The plots
were treated for weed control and fertilized with 80, 100, and
120 pounds of nitrogen per acre in 1972, 1973, and 1974,
respectively. Descriptions of treatments are given in Table 5.
Sugarcane under drip irrigation treatments was watered to re-
place water lost by evaporation as measured from a sunken
pan. Unless rainfall supplied potential pan evaporation (con-
sidered potential evapotranspiration) (14, 15), cane plots were
drip-irrigated with Submatic emitters on Monday, Wednesday,
and Friday. On Monday, metered water was applied to desired
plots to replace percentages of pan evaporation recorded on
the previous Friday, Saturday, and Sunday. Water was applied
on Wednesday to replace percentages of recorded pan evap-
oration the previous Monday and Tuesday, and water was
applied on Friday to replace percentages of recorded pan
evaporation on the previous Wednesday and Thursday. Cane
grown under the furrow irrigation treatment described in Table
5 was irrigated when about 2O to 3O percent of the available
water remained in the top 2 feet. The water was metered onto
each plot. Because of high rainfall in 1972 and 1973, furrow-
irrigated sugarcane was only watered three and two times,
respectively; however, it was irrigated six times in 1974, a dry
year. Rainfall and irrigation water on different treatments for

1972, 1973, and 1974 are reported in Table 6. Height of cane _.

from soil level to last visible dewlap at the top was determined
at various time intervals. Yields as influenced by treatments
and soil properties were evaluated.

TABLE 5. DESCRIPTION OF FURROW AND DRIP IRRIGATION
TREATMENTS ON SUGARCANE IN 1972, 1973, AND 1974,
LOWER RIO GRANDE VALLEY OF TEXAS

Pan evaporation

1972, 1973-74,
Type of irrigation treatment percent percent
Non-irrigatedl 0 0
Drip 252 so?
Drip 50 75
Drip 75 100
Drip 100 125
Furrow3

‘This treatment was irrigated at planting on November 16, 1971,
and in December 1972 and January 1974, after plant cane was cut.

2Refers to percent of pan evaporation.

3Cane was furrow irrigated when available water in top 2 feet was
depleted to 30 percent. Sufficient water was applied to replenish
available water in top 5 feet of soil.

Soil moisture under different treatments was determined
with vacuum gauge tensiometers and neutron scattering
equipment. Salinity and root growth as related to treatments
and soil type and depth were evaluated in 1972, 1973, and
I974.

Sweet Sorghum

The influence of relative degrees of soil removal during
leveling and of moisture levels on yields of sweet sorghum on
Willacy fine sandy loam soil were evaluated in 1967. The

5

TABLE 6. AMOUNT OF WATER USED UNDER DIFFERENT
DRIP AND FURROW IRRIGATION TREATMENTS IN 1972,
1973, AND 1974, LOWER RIO GRANDE VALLEY OF TEXAS

Pan Water Soil Total

evaporation, applied, Rainfall, water water

Treatments percent in in use, in use, in
1972*
Non-irrigated 0 0.00 30.76 30.76
Drip 25 5.47 30.76 36.23
Drip 50 10.93 30.76 41.69
Drip 75 16.40 30.76 47.16
Drip 100 21.86 30.76 52.62
Furrow 13.71 30.76 44.47
1973
Non-irrigated 0 0.00 41.52 3.26 44.78
Drip 50 7.72 41.52 2.47 51.71
Drip 75 11.58 41 .52 1.85 54.95
Drip 100 15.44 41 .52 2.79 59.75
Drip 125 19.30 41 .52 2.71 63.53
Furrow 7.13 41 .52 2.36 51.01
1974

Non-irrigated 0 0.00 24.17 0.30 24.47
Drip 50 12.91 24.17 +0.50 36.58
Drip 75 19.36 24.17 +0.19 43.34
Drip 100 25.82 24.17 +0.75 49.24
Drip 125 32.27 24.17 +0.12 56.32
Furrow 31.48 24.17 0.13 55.78

‘Soil water use was estimated as approximately equal to runoff in
1972. This runoff occurred during a 17-day period in June. Total
rainfall in this period was 10.75 inches. Runoff during this period
was estimated at 50 percent, which was the average amount of soil
water used from about planting or after cutting in case of ratoon
crop and harvesting.

sweet sorghum variety Rio was planted in April 1967. Indi-
vidual sorghum plants were thinned to 3 inches between
plants. Plots were irrigated with aluminum gated pipe and the
water measured with a Sparling flow meter. Soil moisture at 6-,
18-, 30-, 42-, and 54-inch depths was determined at weekly
intervals by the neutron scattering technique before and after
each irrigation. The importance of the relative degree of cut
areas on yields of sweet sorghum was compared. i

RESULTS AND DISCUSSION
Cotton

Medium-Textured Soils. The influence of soil moisture re-
gime on cotton grown on medium-textured soils varied from
year to year. Cotton that was not irrigated after planting pro-
duced from more than 500 pounds in1949 to about 1,000
pounds of lint cotton per acre in 1961. The maximum yield
increase due to supplemental irrigation varied from a high of
about 400 pounds of lint cotton per acre in 1962 to almost no
response in 1950 and 1961.

The relation between rainfall during the first 40 days after
appearance of first bloom and maximum increases‘ in yield
due to irrigation on medium-textured soils is indicated in Fig-
ure 1. The data presented include only the years during which

‘Maximum increase in yield for any specific year = maximum yield
due to irrigation minus yield of non-irrigated cotton.

6

400 '

 
  

9._4s.s4x+3e4

 

u
25
3300
$3 R=—0.9l7
<1:
we
mo-
g 8200 -
“E
Q:
_I~4-
m0
s"; i00-
r:
a
8
O i l l I
O 2 8

_4 _ 6
Roinfol l- inches
Figure 1. Relation between maximum increase in yield of cotton as;
result of irrigation on medium-textured soils and rainfall during the ‘~ s‘;
40 days after appearance of first bloom. ~;

 

e

there was a treatment that did not receive a post-planting i: 
gation. There was a high inverse relation between rainfall “if
ing this critical moisture demand period and yield response‘ .1-
irrigation. ln comparison, the relation between total rai 
during the growing season and maximum yield increase due? .
irrigation only accounted for about 58 percent of the variabi
(r = —0.762). I “

The relation between yield and applied water plus rai f
after first bloom is indicated in Figure 2 for medium-text 
soils. This response curve, which is typically parabolic, i l A
cates that a minimum of 8 to 10 inches of water is 
during the blooming and fruiting period to produce satisfa'
to maximum yields.’ Data in Figures 1 and 2 indicate 
additional water produced little or no further increase in y'u
During the blooming and fruiting period, rainfall supplied 
6 of the needed 8 to 1O inches of water in about half of 
years.’ This helps to explain why yields of cotton on medl”
textured soils are not significantly increased by irrigation 
ing certain years in the Lower Rio Grande Valley of Texa

In addition, rainfall in excess of 8 to 1O inches can
found the response of cotton to irrigation and cause sign‘ 
reduction in cotton yields on medium-textured soils (Fig 
Yields of Stoneville cotton on medium-textured soil 
from 300 pounds per acre during the wet year of 1972 to l,
pounds per acre during the dry year of 1969. During wet
cotton on medium-textured Willacy loam soil developed...
cessive vegetative growth, with a height of 6 to 7 feetgi 
produced very low yields. The influences of soils, cli _'
conditions, and management on response of early- andl
maturing varieties will be discussed later.

.~

  

  
  

‘Refers to yield of about 1,000 pounds of lint cotton per acre.

‘Rainfall data from R. B Orton, State Climatologist, Weather B, _
Airport Station, Austin, Texas, and D. l. Haddock, Advisory - y 
tural Meteorologist, National Weather Bureau Agricultural ‘
Office, Brownsville, Texas.

 

 

 

  

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R=0735

     
   
    
  
   
   
 
    
 
    
  
 
 
  
   
   

0 S f0 I15 2'0 2'5 3'0
APPLIED WATER + RAlNFALL-INCHES

 Relationship between yield of lint cotton and water applied
'nfall during blooming and fruiting period on medium-textured

‘ypical root distribution by cotton on medium-textured
lis indicated in Table 7. Soil depletion studies by
A iya, Namken, and Gerard (1) (Figure 4) and root distribu-
1r» udies indicate that cotton irrigated during the early
 of plant growth appears to develop a shallower root
 than cotton that is not irrigated prior to the fruiting
‘i’ of plant growth. They reported that cotton grown on
i m-textured soils in the Lower Rio Grande Valley of
i may extract water from depths below their primary root
§i(0 to 3 feet) but that the rate of water extraction from
“rdepths may not be sufficient to maintain plant growth
l; periods of peak demand because of lack of sufficient
iling roots.

l 7. TYPICAL ROOT DISTRIBUTION OF COTTON
A‘ ON MEDIUM AND FINE-TEXTURED SOILS, LOWER
y ANDE VALLEY OF TEXAS

Percent roots at various degths, fgg;
0-1 1-2 2-3 3-4 4-5

A finesandy loam 62.1 22.8 1.9 4.9 2.3
nclay 99.0 0.1 0.2 0.1 0.0

he-textured soils. Cotton yields as influenced by soil
f‘ re regimes on the fine-textured soil ranged from slightly
fll pounds for treatments that did not receive any post-
 g irrigation to more than 1,100 pounds per acre on the
 isture level plots. The maximum yield increases due to
nting irrigations were 638, 727, and 465 pounds of lint
‘per acre in 1960, 1961, and 1964, respectively.

I200 h  WILLACY FINE SANDY LOAM

 HARLlNGEN CL AY

I000 -

800 -

600 -

400 -

WELD,POUNDS OF UNT COTTON PER ACRE

200 -

|_ll_lill!llllllllllllllllllllllllllll_lllgllll.llll_lll_ll|_llli.lIl.l_l!l_l!l_l.lll.llI.Illl|.lIl.|ll.l_lllllll.lll.l_llIIIIIII
llll "Illlllllllllllll!llllllllllllllllllllllllllll|!ll.-.-.-..- 
llllllllllllll.llll_lll_llllllllll.;.;.;.;.;.;  

o llllllllllllllllllllllllllllll-llll‘llllllllllllllllllll-lllllllllllllllllllllllllllllll. . . . .
all")!llllllll!|.|!|ll|!|.|;--;-.-=-
O

TZ-I 1
l0.0 15.0
RAINFALL — INCHES

O
U1

Figure 3. Influence of soil type and rainfall during blooming and fruit-
ing period on cotton yields.

The importance of available water to cotton during the
blooming and fruiting stages of plant growth on fine-textured
soils is indicated in Figure 5. The relation between yields and
the total amount of water applied (rainfall and irrigation) after
first bloom indicates that a high level of available water must
be maintained during the blooming and fruiting period to pro-
duce satisfactory yields (1,000 pounds or more of lint cotton
per acre).

As pointed out previously, during certain years rainfall
supplies 5 to 6 inches of water during the blooming and fruit-
ing period. According to the yield curve in Figure 2, this
amount of water plus available soil moisture would produce
over 900 pounds of lint cotton per acre or approximately 80 to
90 percent of the yield potential on medium-textured soils. In
contrast, the same amount of water plus available soil moisture
would produce only about 500 pounds of lint cotton per acre,

or 50 percent of the yield potential on the fine-textured soil

(Figure 5).

The influence of soil moisture regime and stage of plant
growth on moisture depletion from different depths on fine-
textured soils is indicated in Figure 6. Dates of first bloom,
irrigations, and significant rains are also indicated. The soil
moisture depletion patterns in 1960 and 1961, years in which
summer rainfall was scant, were almost identical. Moisture
depletion at different soil depths is an index of active root
development and relative wetness or dryness of the soil, ac-
cording to Vazquez and Taylor (19) and Taylor and Haddock
(18). Moisture depletion under dry treatment was restricted to
the surface foot until 90 to 100 percent of the available water
in that area was depleted. Significant amounts of water were
not extracted from the third foot until the plants ceased grow-
ing and were severely wilted.

 

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'/.\'_\> .\o—-\ 6o \€*0 \AATA\Q\
4 7 w w eff» \.=\_ A» 1

(INCHES /FO0Tl

SOIL WATER

giRRic-z/triowsxl;

APRIL MAY JUNE JULY AUG.

Figure 4. Soil water changes for a 5-foot profile on Willacy loam soil as
influenced by soil moisture treatments and cotton in 1959. (See Table
1 for treatment description.)

Soil moisture depletion under frequently irrigated cotton
was largely restricted to the top foot before and following the
first irrigation. Extraction of water from the second and third
feet increased as the plants increased in growth. Root de-
velopment apparently increased in the second foot during the
blooming and fruiting period. Percentage of roots by weight
did indicate slightly higher percentages of roots in the second
foot under moisture regimes where the cotton was irrigated
during the blooming and fruiting period. However, moisture
depletion patterns are probably better indices of root activity
than the percentage by weight data shown in Table 7.

The results indicate that non-irrigated cotton was able to
extract significant amounts of water from the second and third
feet or below its primary root zone (surface foot). However,
moisture extraction from the second and third feet was not
sufficient to meet the needs of plants, especially for about 1O to
20 days after initiation of blooming when the available soil
moisture supply of the surface foot was depleted. This was
reflected in the cessation of growth and reduction in yield of
cotton grown under dry treatments.

8

   
    
  
   
  
   
   
   
  
   
   
 
 
  
 
   
  

Studies with early maturing cotton types. Yields of A
on Harlingen clay soil was significantly influenced by
ties and years (Figure 7). Yields of Stoneville cotton g H
Harlingen clay soils, unlike Stoneville cottons gro
medium-textured soils, were not influenced by excessi 
fall during the years of 1969 through 1974 (Figure 3}
ever, in 1972, 1973, and 1974 Tamcot §P-37 produced‘
yields in 130 days than Stoneville 213 and Paymaster 
Tamcot SP-37 and Paymaster Dwarf produced hig 
yields in 1972 than Stoneville 213. Yields by Tamcot t
1972 and 1973, both wet years, and 1974, a dry year, ‘
800 pounds per acre in 130 days indicate that this;
offers an excellent opportunity to shorten the cotton f,
tion season by 1O to 2O days on these soils. a 

Differential early yield response of Stoneville 213 .'
compared to 1973 is believed an expression of dig
early fruiting conditions. The 1972 crop year was 
heavy and frequent rainfall; the 1973 cotton crop 
also wet, but early fruiting conditions were relatively?
ideal for cotton production. 

The 1972 and 1973 crop years were very w"
moisture level treatments did not significantly influe l“
in 1972 and 1973, the yields for these 2 years are av
all moisture levels; however, the yield data for 197 y.
year, are from the highest moisture level, or cottonfl
ceived the equivalent of three irrigations during the 
and fruiting period (Figure 7). Rainfall of 5.7 inchesd

I200‘

6
o
9

‘é

  
 

A _
v=4z|4x z

600' .
R =092 l‘;

4001

POUNDS 0F LINT COTTON PER ACRE
m
O
Q

0o 5 1'0 1's 210T,
APPLIED WATER + RAlNFALL-INC 

Figure 5. Relationship between yield of lint cotton per acret
applied plus rainfall during blooming and fruiting period on,
clay soil. ,

     
   

. l.2 0.60
PPT. PPT. PPT.

  

' -sou. MOISTURE rnsarmzur A t
I FT. INCREMENTS |_|Q
PPT.

_ FIRST BLOOM

 

son. MOISTURE TREATMENT a
5 I FT. mcasmswrs

i _ '1‘ '1‘ T ’l‘
rs l.2 0.60 no
PPT. PPT. PPT. PPT.
FIRST atoom

\/

   

' /\ /\ /\
2.3a" 2.52"

l l l l l

l

/\ /\
3.25" 3.50 2.23“

    
 

Figure 6. Soil water changes for a 5-foot
profile on Harlingen clay soil as influ-

 
  
  
   
  
  
  
  
   
    
   
 
  
  
   
  

Fr in 1974 was considered equivalent to one irrigation.
tion requirements for cotton production on clay soils
I been reported to number four to six irrigations during the
y, ing and fruiting period (9). Early and total yields of all
j ies declined from 1972 and 1974 (Figure 7). This was
 ially true 0f Paymaster Dwarf. Lower plant densities may
T contributed to lower yields by this variety. Lower yields
74 by all varieties may also have been partially caused by
 for available soil moisture.

Yields of Stoneville 213 and Tamcot SP-37 in 1974 were a
rfunction of applied water plus rainfall during the bloom-
land fruiting period (Figure 8). This predictive yield equa-
is almost identical to the yield equation shown in Figure 5
I hese equations emphasize the dominant role of water in
l} production on,-.-cl_ay soils. The equivalent of three irri-
_ s produced about 900 to 1,000 pounds per acre of lint
in. On clay soils a 130- to 140-day cotton crop required
i? 40 percent less waterthan a 150- to 160-day cotton crop.
jyYields of Tamcot SP-37 and Stoneville 213 cottons, as
V- nced by treatments and varieties on Willacy fine sandy

 ‘r ‘ enced by soil moisture treatments and cot-
-‘ 30 30 l0 2Q 30 l0 2Q 3O lo 30 l9 ton in 1960. (Treatment descriptions are in
~ APR. MAY JUNE JULY Table 2.)

loam soil, are reported in Figures 9 through 12. Tamcot SP-37
was significantly earlier and higher yielding than Stoneville 213
and, despite high rainfall in July, produced over 800 pounds of
lint cotton per acre. Highest yields of Tamcot SP-37 grown
after winter fallow and winter crop were about 700 and 830
pounds per acre with no and one irrigation, respectively (Fig-
ures 9 and 10). In fact irrigated Tamcot SP-37 grown after
winter fallow produced only 60 to 70 percent of the yield of
non-irrigated Tamcot SP-37. On the other hand, average
maximum yields of Stoneville 213 were only about 60 to 70
percent of maximum yields of Tamcot SP-37 (Figure 11). Irriga-
tion of Stoneville 213 grown after winter fallow reduced yields
by 40 to 60 percent (Figure 12). One irrigation caused a slight
increase in yields of Stoneville 213 grown after a winter crop
(Figure 11).

In summary, there is a complex interaction between varie-
ties, irrigation, and previous cropping history. Reductions in
cotton yields on soils that promote vegetative growth can be
partially alleviated by planting early maturing cotton types
such as Tamcot SP-37 after a winter crop. Stress for nitrogen

9

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__=______=____________________________________________L n

F.
R
 a  a .................. .._.________.___._____.___.___._._______,______E n
w. w m M ...w»\w»$§ww-\\\\\\\\\§ a
m m m. w
a w. m a __________________ 2
w m m aH.r.n.n.u.s___.___.____.____.___._._as:_._.___.___ ..................... a m
\\\ K _____ ....... -- t\\\\\\\\\\\\\\\\\\
_ _ _ _ _ lilrli|lll
w w w w w w
w. m a e 4 z

wmo< 5a zoCoo E: do mezzo“. dd;

Figure 7 Influence of varieties and
years on 130- and ISO-day lint cot-
ton yields.

y= 59.2|X + s is
R’= o 9e a g

A

I000 -

_
0
O

_ _
O 0
Q . Q 2

8 6
wmo< mwa 20.500 ._.Z_._ m0 wnzzoa dd;

400%

2o  
APPLIED WATER + RAINFALL — (INCHES?

Figure 8. Relation between yield of lint cotton
and water applied plus rainfall during blooming
and fruiting period on Harlingen clay in 1974.
1O

    

a a    Kusskf zga? \~  ti,‘ .‘ Iyhlixwrz;
-  a
O
I

”
*"a00-
f
E l’
_-. .,
t"
 6 Q O " k /
 A
l

 400 »- g

g - 0 — 0
 1 —— X — I
fig“.  '-
9" r '_ A ‘i 2
 1 I 1
 7/5 7/l5 7/25 8/5

   
   

. (

DATE OF HARVEST

3%
 Yields of Tamcot SP-37 after a winter crop as influenced by
"tlltarvest and irrigation on Willacy loam in 1975.

 Yields of Tamcot SP-37 after fallow as influenced by time of
and irrigation on Willacy loam soil in 1975.

NO. OF IRRIGATIONS
-0- 0
..—X- l
G
0
J X
Q /A
. X/
/A
X
JA/
_ l 1 1 1
1,; 7/5 7/l5 7/25 3/5 3A5

DATE OF HARVEST

LU 1000-

cc

o

<

n:

LU

0. s00-

z

E NO. OF IRRIGATIONS

O ——G—— O

Q _

P e00 _x_ l

% -'-A—‘ 2 X
u. /0
O 400 I x/A
w _

0 /0

Z X/

8 ° A

Q. A/

0- 200-

ifi

; 6

A
l l I
7/5 1/15 1/25 8/5 

DATE OF HARVEST

Figure 11. Yields of Stoneville 213 after winter crop“ as influenced by
time of harvest and irrigation on Willacy loam soil in 1975.

Figure 12. Yields of Stoneville 213 after fallow as influenced by time of
harvest and irrigation on Willacy loam soil in 1975.

Lu |000 -

CC

o

<

II

Hf e00 -

z

E NO. OF IRRIGATIONS

O —0- 0

O e00 - —X— I

E —-A— 2

-' 0
LL

O 400 /
8 0

Z

D 9/ X
O /
D.

- 200 - A

Q X

ii 9 X”// /,/’//
>-

X/éliz/A  
A 1 1

I
7/5 7/I5 7/25 8/5
DATE OF HARVEST

11

and moisture are two factors which tend t0 reduce vegetative
growth and to reduce the hazard of yield and profit losses due
to adverse climatic conditions. A second alternative is to plant
Tamcot SP-37 and not irrigate cotton planted on these soil
types if the profile is essentially full of moisture at planting
time. Rainfall could eliminate the influence of the latter alter-
native.

Grain Sorghum

Grain sorghum yields on a moisture level-plant spacing
experiment on Harlingen clay soil in 1968 were lower than
average, but moisture level-plant spacing treatments in 1969
had a significant influence on grain sorghum yields on the
same soil. The yield levels shown in Figures 13 and 14 are
commonly produced. These data indicate that maximum
yields were not attained. However, yield of grain sorghum per
inch of water by single-row grain was a maximum of 240
pounds per inch of water when irrigated two times (Table 8).
Yields of double-row grain per inch of water did not attain a
maximum but was 258 pounds per inch of water (Table 8)
when irrigated four times. The yield difference between
double-row grain irrigated four times and single-row grain irri-
gated twice was 700 pounds per acre. Before 1975, grain sor-
ghum prices were generally below $2 per 100 pounds. At $2
per 100 pounds it probably would not be practical to irrigate
double-row grain sorghum four times.

In 1969, date-of-planting studies were conducted on
Willacy loam and Harlingen clay soils with single- and
double-row grain sorghum. Yields of over 5,000 pounds per
acre were produced on Willacy loam soil (Table 9). Burleson,
Cowley, and Dacus (4) reported similar yields on loam type
soils in South Texas.

In 1970, experiments with moderate to very high plant
populations of double-row grain sorghum produced from
3,400 to 4,200 pounds per acre on Harlingen clay soil (Table
10). Available soil moisture was not a limiting factor in 1970 as

. . a result of high rainfall. Yields were not significantly influenced

by seeding rate.

Average yields of grain sorghum on Willacy fine sandy
loam in 1973 and 1974 are reported in Table 11. The lack of
response to irrigation in 1974, a relatively dry year, is surprising
but common on these soils. Yield levels on this soil and on
Harlingen clay soil emphasize the low yield potential of grain
sorghum in South Texas. Lysimetric data with grain sorghum
on medium-textured soils indicate that during dry years this
crop may extract 10 to 20 percent of its water from the water
table. It should be emphasized that 2.7 inches of rain fell dur-
ing the preboot to boot stage, a critical moisture period for
grain sorghum. This fact, plus the low yield potential, probably
is responsible for the low water requirement of grain sorghum.
It is common for dryland grain to produce comparable yields
with irrigated grains on medium-textured soils.

Average root growth by grain sorghum in 1969 on Har-
lingen clay and in 1973 and 1974 on Willacy fine sandy loam
soil at different soil depths is shown in Table 12. Concentration
of roots on Harlingen clay soils is greater in surface soil than on
Willacy loam soil. The higher root concentrations at lower soil
depths in 1974 than in 1973 was probably because available
soil moisture at the soil surface was less in 1974, a dry year,

12

5000-

4000-

3000-

—o— DOUBLE now,
—x— smeu: no

    
    
   
      
  
   
  
    
   
  

2000

~

YIELD, POUNDS PER ACFIE

I000

o I l l l 
O I 2 3 4 ‘ 

NUMBER 0F IRRIGATIONS

Figure 13. Influence of irrigation on yields of single- and d
grain sorghum on Harlingen clay soil.

I.

5000

4000

3000 -

2000 -

‘WELD,POUNDS PER ACRE

  

—x— smstc - -

I000 - -o— oouau:  

WATER USED-—lNCHES

Figure 14. Relationship between water use and yield of 
double-row grain sorghum on Harlingen clay soil. I 

than in 1973, a wet year. Typical moisture extraction
sorghum on Harlingen clay and Willacy loam soil 
1973, and 1974 is shown in Figures 15, 16, and 17, 1.;
ly. Grain sorghum grown on Harlingen clay extractf;
its water from the top 2 feet of soil. Root develop 
restricted on soils such as Harlingen clay. High 
irrigation in 1973 maintained high soil moisture co 
2 to 4 feet. In 1974 depletion was a function of

 
  
 

l. YIELDS OF GRAIN SORGHUM ON SINGLE AND DOUBLE ROWS AS INFLUENCED BY IRRIGATION TREATMENT ON
 EN CLAY IN 1969, LOWER RIO GRANDE VALLEY OF TEXASl

Row configuration

  
    

_ Yield, lb/acre Moisture use, in Lb grain/in of water

 Irrigations2 Singles Double4 Single Double Single Double
‘ ed 840 430 7.8 8.8 108 49

 ion 2,800 1,745 11 .9 12.0 235 145

I ttions 3,725 3,225 15.5 14.5 240 222

 tions 4,065 4,445 17.7 17.2 230 258

 

 
  
  
  
    
  
 
    
  

l’, , regardless of treatment, was irrigated up.
 irrigation after boot stage.

- single row on top of 38-inch beds.

 two rows 10 inches apart on top of 38-inch beds.

ts, but root development and moisture extraction
“nificant at lower soil depths (Figure 17 and Table 12).
ierally clay soils hold less available water per foot than
m and sometimes loam soils, and they often impede
I h which means these soils hold less available water

9. GRAIN SORGHUM YIELDS ON WILLACY LOAM
ARLINGEN CLAY AS INFLUENCED BY DATE OF
NG IN 1969, LOWER RIO GRANDE VALLEY OF

   
   
   
  
   
   
   
  
   
   
   
  
   
  
 
  
  

_v Willacy loam, Harlingen clay,
iplanting lb/acrel Date of planting lb/acrez
 /69 5160 3/21/69 3300
f *1/69 4640 4/28/69 3725
. y

 /69

I I lowgrain sorghum.
' 0w grain sorghum.
~ tings were eaten by birds.

 ective root zone. Because of this fact, crops grown on
Oils require more frequent irrigation than crops grown
‘rium-textured soils. This partly explains why clay soils
n considered drouthy soils.

‘s-oes

l Ico tomato yields ranged from about 1O to 30 tons per
_l Willacy loam soils in 1962-64 (Table 13). A preplant
in, timely rains, and ideal climatic conditions in 1962
 bably responsible for high yields of non-irrigated to-
- and lack of response to irrigation. In 1963 and 1964,
tomatoes produced 3 to 1O tons more per acre when
f v than when not irrigated or when grown under low soil
'~ - conditions. As indicated in Figure 18, the incidence
I m-end rot (BER) and the number of days of stress in
3 ary root zone after initiation of blooming is parabolic.
‘ercept occurs at 7 days, and this relationship suggests
er prevailing climatic conditions Chico tomatoes need
 rigated 7 to 15 days after initiation of blooming to keep
a a low level of incidence.

ar tomato yields on fine-textured Harlingen clay soil

,- from 2 to 10 tons per acre (Table 14). Even under high
g re level conditions incidence of BER of pear tomatoes

 

TABLE 10. INFLUENCE OF POUNDS OF SEED PER ACRE ON
YIELDS OF DOUBLE-ROW GRAIN SORGHUM PLANTED ON
HARLINGEN CLAY IN 1970, LOWER RIO GRANDE VALLEY
OF TEXAS

Pounds of seed/acre Yield, pounds/acre

8 3860
12 3860
16 4220
20 3785
24 3715
28 3770
32 3690
36 3410

hLSf

*Not significant.

TABLE 11. YIELDS OF GRAIN SORGHUM IN 1973 AND 1974
AS INFLUENCED BY FURROW AND DRIP IRRIGATION ON
WILLACY FINE SANDY LOAM SOIL, LOWER RIO GRANDE
VALLEY OF TEXAS

Water use
Irrigation Number Water use, Yield, efficiency,
treatments irrigations in lb/acre lb/in of water
1973
F urrow 2 18.2 3820 209
1974
Drip irrigation
treatments
(percent pan evaporation)

0 7.4 3860 552

50 11.0 3580 325

100 13.1 3710 283

150 14.1 4405 312

N.S.*

*Not significant.

was high, generally 2O to almost 5O percent. Low yields, high
water requirements, and high BER incidence probably make
tomato production on these soils unprofitable.

Typical moisture extraction at different depths on two
soils is shown in Figures 19, 20, 21, and 22. Moisture deple-
tion data indicate that Chico tomatoes were able to extract

13

Figure 15. Soil water
changes for a 5-foot profile
on Harlingen clay soil as in~
fluenced by irrigated
single-row grain sorghum.

SOIL MOISTURE - INCHES

5.0

4.0

I.O

moisture from 3 to 4 feet on medium-textured Willacy loam
soils (Figures 19 and 20). However, moisture extraction on

fine-textured Harlingen clay soil was largely restricted to the
top foot. Significant moisture depletion from the second foot

did not occur until about 3O days after the first bloom in the
case of the dry treatment (Figure 21) and 6O days after first
bloom in the case of the wet treatment (Figure 22). Root growth
by tomatoes on the two soils show that root development is
more extensive on Willacy loam than on Harlingen clay soil

(Table 15).

Figure 16. Soil water
changes for a 4-foot profile
on Willacy loam soil as in-
fluenced by irrigated
single-row grain sorghum
during a wet year (1973).

14

SOIL MOISTURE — INCHES

5.0

4.0

3.0

2.0

I.O

x____'X-—- X‘. X__x

  
 
 
 
 
 
  
  
 
 

‘ tons per acre in 1972, 1973, and 1974 (Table 16kt

Sugarcane a 5
Yields as influenced by treatments ranged fr,’

maximum yields harvested in 1972, 1973, and f
55, and 52 tons per acre, respectively. Yields we ~ 1 
influenced by irrigation treatments in 1972 and 1 . I.
1973 (Table 16). The 1972 and 1973 crop 
rainfall, but the 1974 crop year was unusually dry?
yields for 3 years are reported in Table 17. The 



‘A\QiQA“A__A m 

/%p°\o\ ?\o—o \o

Q§Q§0_0\o 

\,.V _g .

2.72" I 1.46" e30"

1 l 11h ‘l i l 1 l 1 1
IO 3O IO 3O IO 3O IO

APRIL MAY JUNE JULY

  
    
  
   
   
 
   
  
  
 
  
  
   
  

 i uced per inch of water ranged from 0.8 to almost 1.2
 h inch of water produced 1 ton or more of cane in the
 »; of 20 to 50 tons per acre (Figure 23). However, one
jsrwater produced slightly less than 1.0 ton per inch of
 n yields were above 5O tons per acre (Figure 23).
 lodges when it attains a yield level of 4O to 5O tons
 . After attaining this production level, response of cane
 i water may be limited by such factors as lodging, soil
 s, and inherent varietal differences.

 12. ROOT GROWTH BY GRAIN SORGHUM ON HAR-
 AND WILLACY FINE SANDY LOAM so||_s m 1969
 73-14, RESPECTIVELY, LOWER RIO GRANDE VALLEY

Percent roots, Percent roots,

Harlingen clay Willacy fine sandy loam
1969 1973 1974

58 48 27
16 22 29
17 13 13

8 10 18

1 8 12

 effect of soil properties and irrigation treatments on
yfj- cane in 1974 is tabulated in Table 18. The soil prop-
erences of medium-textured soil and fine-textured soil
ijcated in Table 4. The clay content of the medium-
‘, soil decreasefs with depth. The soil is moderately
 to a depth of 4 feet, and the salinity of this soil is
  depth of 4 feet. The fine-textured soil is low in per-
il , and electrical conductivity, expressed in mmhosper
l eased to 4 and 6 at 3 and 4 feet, respectively (Table 4).
Jlproper irrigation, yields of cane were markedly less on

' O _ _____ /~ ~\X X\x\%\ sou. DEPTH-FT.

- LO~\Q .

\/\ \\‘* *7‘ '

_ ——X — 2

. "_" -- O -— 3

.. --A- 4

- 0—- 5
Figure 17. Soil water
é I l l I l l changes for a 5-foot profile
i. -o on Willacy loam soil as in-
 l0 3Q lQ 3O IO 3O fluenced by drip-irrigated
AP R‘ L M AY J  grain sorghum during a dry

year (1974). -- ~

clay soils than on medium-textured soils. Comparison of yields
of non-irrigated, irrigated at 5O percent pan evaporation, and
furrow irrigated sugarcane on the medium-textured soil em-
phasizes this observation (Table 18). The furrow irrigated cane,
irrigated six times in 1974, produced 5O tons per acre on
medium-textured soil but only 31.5 tons per acre on fine-
textured soil (Table 18). Six irrigations produced high cane
yields on the medium-textured soil, but cane on the fine-
textured soil should have nine or ten irrigations instead of six.

Growth data. The influences of treatments and soil prop-
erties on the growth of cane in 1974 are reported in Figures 24,

 

so
F r +
¢ A
‘\- 40 Y=-O.9l+O.Ol83X2 R=o.a23--
l"
O
Z
Q 3O
Z
U]
E 2o
0
‘D
(D
O
.1 IO
d:
+ + + +
o.
o 20 so 40   so
DAYS

Figure 18. Relationship between percent of blossom-end rot of Chico
tomatoes and number of days after initiation of blooming before irriga-
tion or significant rain on medium-textured soil.

15

TABLE 13. INFLUENCE OF IRRIGATION TREATMENTS ON
SPRING PLANTED CHICO TOMATOES ON WILLACY LOAM
SOIL IN 1962, 1963, AND 1964, RIO GRANDE VALLEY OF
TEXAS

Irrigation Number Water use, Tons/in
treatments irrigations Tons/acre in of water
1.92
wet 5 32.0 25.2 1.3
medium 3 30.6 18.5 1.7
drY 2 34.1 20.2 1.7
very dry 1 21.9 15.5 1.4
not irrigated 0 37.8 9.1 4.2
12?.

wet 6 20.3 ' 23.7 0.9
medium 3 13.4 20.0 0.7

_ dry 1 12.0 14.0 0.9
very dry 1 8.8 16.8 0.5
not irrigated 0 12.6 10.0 1.3

1951

wet 5 16.5 20.0 0.8
medium 3 14.7 16.9 0.9
drv 2 1 1.6 14.9 0.8
very dry 1 9.8 12.9 0.8
not irrigated 0 12.2 8.0 1.5

25, and 26. In a hot, dry year (such as 1974), it is oftendifficult
to maintain favorable moisture conditions for cane growth.
Short cane was evident in many growers’ fields because of low
moisture conditions. Low moisture conditions may be caused
by improper or infrequent irrigations or may result from soil

 
   
   
   
     
  
  
   
 

TABLE 14. INFLUENCE 0i= IRRIGATION TREATM;
YIELDS 0i= SPRING PLANTED CHICO TOMATOES 
LINGEN CLAY SOIL, LOWER RIO GRANDE VAL
TEXAS _’

Irrigation Number Yield, Water use,  I 
treatment irrigations tons/acre in =
L92 *-
wet s 6.5 “ 1‘ 16.9
medium 2 5.9 12.5
dry 1 4.9 11.8
non-irrigated 0 4.1 8.8
wet 3 5.3 15.1 a   
medium 2 5.7 13.4
dry 1 3.1 11.6
E2
wet 2 3.2 10.8
non-irrigated 0 1 .2 7.4
19L
wet 3 10.1 9.0 
non-irrigated 0 2.3 7.1 ‘i 

hardpans or excessive soil salinity. Hardpans reduc
able soil water reservoir, causing stress and retag‘
growth between irrigations. Salty soils act as dry  
salinity reduces the amount of water availa
growth. Clay soils are less permeable t0 water and 4 ‘I
development. Plants 0n clay soils often do not 
able water reservoir that plants have on more 1 i 
and clay loam soils. The differential growth of‘ 

LL. .. ‘

i 5 Q‘ ‘ - - t ’ .

U) \’_\\/’§\

iu \

I .....__ \

O 4.  t __\

E T ‘u. a - \’ \s

' ~\_\‘ fl%%%

u] 3. 

q; \ 
3 \

I; TREATMENT ‘- - \ \

6 2- i FT. INCRENIENTS T’

2

.1

— l‘ " 0.31" 1

C) 0.791 II Q44‘

u) pp-[FIRST PPT 0.19 P" . 

BLOOM PPT- .. "99. t. 
Q37 p91;  

Figure 19. Moisture depletion at different soil
depths by non-irrigated Chico tomatoes grown
on Willacy loam soil in 1962.

16

i0 20 30 i0 2'0 $0 i0 £0 :80 
MARCH APRIL I

.2-

M AY  

  

. ‘1;,.:,-.~_.rr,~f;<;<,»  m,

        
   

  
 
      

? H
2.40

PPT.

, 1.4a"
bhbsdm PPT-
I

  
     
 
 

. . . J . , . . . fi T . . 1
IO 2O 3O IO 2O 3O IO 2O 3O IO 2O 3O IO 2O
MARCH APRIL MAY JUNE JULY

by Chico tomatoes grown on Willacy loam and
irrigated twice in 1962.

 \--4\ "'b\ ‘\
 \\ /»\\ / \\ l \\ _' ' 5r
~ ’- \ L. \
" o  .0 \\
7 g . . \ '
A canon a‘. \_ 4
 '"" ~
 T u \ 2'
 O.79?PP‘I'.
 FIRST BLOOM u PPT, y |'
 TREATMENTmB-I QPT- .. L00"
 I FT. mcmzmeursfmg PHI ,, PPT-
(a ' 500i. also  
 D        30    Figure 20. Moisture depletion atdifferent depths
 MARCH APRIL MAY JUNE
i  _(~\
 \ / H-__ I \ _
 .\_/_ _ . ' ' \: <__-___- - - _ ' _ '
5 '%l_ \---¢
2
O-85"PP .
TREATMENT
IFT INCREMENTS ',

Figure 21. Moisture deple-
tion at different soil depths
by Chico tomatoes grown
with one irrigation on Har-
lingen clay in 1967.

row irrigated cane on clay and medium-textured soils Willacy loam soil (l5). However, the time interval on the clay
if izes the effect of-Isoil types on cane growth (Figures 24 should be closer to 2 weeks, the same as the recommended
"). Six irrigations produced excellent growth and yield of interval for Harlingen clay soil (i5). As shown in Figure 26,
i‘ medium-textured soil but were not adequate for drip irrigated cane at 125 percent pan evaporation was almost
 um growth and yield of cane on fine-textured soils (Fig- the same height on the medium- and fine-textured soil, indicat-
). The time interval between irrigations was about 3 ing that under favorable water management cane growth and
A’ which is the approximate interval recommended for yields were almost identical under different soil conditions.

17

Root development and soil salinity. Root development is
influenced by type of irrigation, such as furrow versus drip, and
by soil types (Table 19). Sugarcane root development, when
drip irrigated at 125 percent pan evaporation, was consid-
erably greater than root development by furrow-irrigated cane.
These differences were especially great in 1974 because of the
unusually dry weather. Low root development at 0-6 inches
under furrow irrigation is a reflection of dry soil conditions at
the time of sampling. Sampling at a time more favorable for
soil moisture conditions would have resulted in greater root
development at 0-6 inches. The yields and growth of cane
irrigated at 125 percent pan evaporation indicate that if

  
  
   
  
 
  
   
  

-
moisture is supplied, plants with less root development f
produce yields comparable with those of plants with more '"_
development and growth (Table 19). The influence of _
properties on root development and cane growth irrigat‘
125 percent pan evaporation are shown in Figure 27. Re 
less of treatment, root development in 1974 was more e i,
sive on the permeable than on the relatively impermeable ,_
soil. I '”‘ 
Soil properties have a marked influence on roots i"
water and on the content of salt in the soil profile. The el‘
cal conductivities of soil at different depths of furrow irri
cane as influenced by soil properties are indicated in F

    
 
 
  
  
 
  
  
 
 
  
  
 
  
   
  

28. The increased clay and lower soil permeability incre’
salinity of the soil at 3 and 4 feet. In South Texas, accum
tions of salts at lower soil depth often occur on soils f
increased clay contents.

TABLE 15. ROOT DISTRIBUTION OF TOMATOES AS INFLU-
ENCED BY SOIL TYPE AND DEPTH, LOWER RIO GRANDE
VALLEY OF TEXAS

$0ll dépth, feet Sweet SQfghum

Soil 0-1 1-2 2-3 3-4 4-5 In 1967 the yields of sweet sorghum varied with s g
P respect to different degrees of cut (removal of topsoil) (T
————————— —— ercent ——--—------— . . . . _ _ _ _ >
wmacy |oam1 85.6 133 Q8 0.2 0.1 20). This SO|l is a Willacy fine sandy loam with IHCFGGSIHQ:
Hamngen clay; 963 3] on on 0'0 and caliche at lower SOll depths. On the surface, these y“

normally have 12 to 15 percent clay. However, clay c 
increases to 2O to 40 percent at the 12- to 24-inch 
Obviously, severe cuts can change the textural and, the P

1 Data from Bloodworth, Burleson, and Cowley (2).
2Root distribution determined using radioactive P.

TABLE 16. YIELDS AND QUALITY OF NCO 310 SUGARCANE AS INFLUENCED BY DRIP AND FURROW IRRIGATION 
MENTS IN 1972,1973 AND 1974, LOWER RIO GRANDE VALLEY OF TEXAS‘ “i

Pan -
evaporation, Yield, Tons cane/ Tons
Treatments percent tons/acre in of water sugar/acre Pol Brix
1972
Non~irrigated o 35.2 c2 1.14 4.04 15.9 a 18.9
Drip 25 42.4 bc 1.17 4.73 15.6 a 18.8
Drip 50 47.5 ab 1.14 4.86 14.4 ab 17.8
Drip 75 47.9 ab 1.02 5.36 15.6 a 18.7
Drip 100 51.7 a 0.98 4.69 12.9 b 16.3
Furrow 44.9 ab 1.01 4.60 14.5 a 17.9
1973
Non-irrigated 0 47.8 1.07 4.89 14.4 17.6
Drip 5O 48.4 1.03 4.69 12.8 16.2
Drip 75 50.8 0.94 5.80 15.8 18.8
Drip 100 49.4 0.92 5.17 14.7 17.8
Drip 125 55.2 0.83 5.14 13.3 16.7
Furrow 51.4 0.87 5.10 14.0 17.2
N.S. N.S.
1974 .
Non-irrigated 0 23.9 c 0.98 2.03 12.6 b 15.8
Drip 50 40.5 b 1.11 4.16 14.3 a 17.2
Drip 75 45.1 ab 1.06 4.65 14.4 a 17.3
Drip 100 49.3 ab 1.00 4.85 14.0 a 17.0
Drip 125 52.1 a 0.93 5.41 14.6 a 17.4
Furrow 43.5 ab 0.78 4.64 14.7 a '17.7

lAppreciation is expressed to B. Ashby Smith, research chemist, USDA Food Crops Utilization Research Laboratory, for milling 

quent analyses of cane samples. t
2Values with common letters are not significantly different at the 5 percent level of Duncan's Multiple Range Test.
3Not significant.

18

1P

   
     
    
  

        

"<4 ' "51
........... __ . _-_4
\
'-._\
 \ '
"~-----‘..:. 2,
0.05" 3
W. PPT PPT
 TREATMENT 2 40..
 I FT. INCREMENTS PM _
   5m ~ ~ " ~
 | ¢ 2.00" 2.00" _ ,
 at i l Figure 22f? Moisture geplfi-
 v v v ' f ‘ ‘ ' ' * r ' ' ' ' in di rn i
 |0 20 s0 IO 20 30 |0 20 a0 :0 20 30 IO 20 30 iafitfiéiiitfofofrengtgcé§gfgfivri
 WI ['88 lffl a lOflS OI‘!
  MARCH APRIL MAY JUNE JULY Harlingenclayigil967.

    

X
0.84 + 0.003 X

2

9‘
R : 0.90

.0" f;

   

l n 1 l l

[Q 2Q 3Q 4Q 5Q 6Q Figure 23. Relationship be-
tween water use and sugar-
WATER USE "" |NCHES cane yields.

19

TABLE 17. THREE-YEAR AVERAGE YIELDS OF SUGARCANE
AS INFLUENCED BY DRIP AND FURROW IRRIGATIONS,

LOWER RIO GRANDE VALLEY OF TEXAS

Percent

pan Yield, Tons
Treatment evaporation tons/acre sugar/acre
Non-irrigated 0 35.7 3.65
Drip 25* 42.4* 4.73*
Drip 50 45.5 4.57
Drip 75 47.9 5.27
Drip 100 50.1 4.90
Drip 125*‘ 53.7“ 5.28“
Furrow 46.6 4.78

‘Evaluated in 1972 only.
"Evaluated in 1973 and 1974 only.

TABLE 18. INFLUENCE OF SOIL PROPERTIES ON YIELD

RESPONSES TO DRIP AND FURROW IRRIGATION IN 1974,
LOWER RIO GRANDE VALLEY OF TEXAS

Yield, tons cane/acre

Pan

. Permeability
evaporation,

Treatments percent High Moderate Low Avg.
Non-irrigated 0 26.0 27.4 13.3 23.9 c1
Drip 50 40.8 46.1 34.7 40.5 b
Drip 75 46.4 48.0 40.8 45.1 ab
Drip 100 40.5 56.5 50.8 49.3 ab
Drip 125 45.9 54.8 55.5 52.1 a
Furrow 50.3 48.7 31.5 43.5 ab

1Values with common letters are not significantly different at the
5 percent level of Duncan's Multiple Range Test.

TABLE 19. INFLUENCE OF SOIL PROPERTIES ON ROOT

DEVELOPMENT BY FURROW-IRRIGATED SUGARCANE AND
SUGARCANE IRRIGATED AT 125 PERCENT PAN EVAPORA-
TION IN 1974

125 percent

Furrow irrigated Cane pan evaporation

Soil type Soil type
Depth, Medium- Fine- Medium- Fine-
inches textured textured textured textured
Root growth (mm of root/cm3 of soil)
0-6 1.0 0.8 6.4 2.1
6-12 2.1 1.3 2.7 0.6
12-24 ' 0.9 0.4 . 0.8 0.3
24-36 0.5 0.2 0.4 0.1
36-48 0.7 0.0 0.1 0.1
Percent
relative
growth 49 27 100 39

chemical and physical properties of the soil surface. After cut- a

ting, soil with a clay loam to a clay surface requires different
fertility and water management than a similar uncut area.
Yields of non-irrigated sweet sorghum on severely cut,
moderately cut, and uncut areas produced 7, 12, and 17.5 tons

20

    
 
   
 
 
   
 
    
   
   
  
  
   
 
  
 
  
   
  
 
 
 
 
 
  
   

per acre, respectively (Table 20). Frequent light irrigatio 
cut areas increased the yields of sweet sorghum to about-i:
tons per acre. irrigations had essentially no affect on yiel
sweet sorghum in uncut areas (Table 20). 

TABLE 20. INFLUENCE OF DIFFERENTIALLY CUT AR
OF WILLACY LOAM SOIL ON YIELDS OF SWEET SORG i"
IN 1967, LOWER RIO GRANDE VAIiILEY OF TEXAS I

Description of Number Strip : 
cut area lrrigations tonsl=
Severely cut 01 7.1“.
Moderately cut 01 
Uncut 0‘ 17.5 *
Severely cut 5 14.3 I3
Uncut 5 17.

1This sweet sorghum was irrigated at planting time but was 
gated during growing season; however, a rain at boot stage
equivalent to one irrigation. ' *

Hardpans, compacted zones, or cut areas such 
scribed above can impede root growth and water infilt 
Soils with hardpans, compacted zones, or cut areas at
like soils that have shallow reservoirs of available wate 
as the Harlingen clay and Mercedes clay soils described’ 
in this text. 

These cut areas can require higher nitrogen and (if:
plications to offset the usual deficiencies of these - 
elements. Subsoiling or chiseling, planting of cover cr 
applying more frequent irrigations can help allevi
minimize the adverse effects of cut areas, hardpans, a 
pacted zones. The adverse effects of hardpans and be 
effects of chiseling were previously described and repo 

ACKNOWLEDGMENT

For his contribution of time, work, enthusiasm, a 
ership, the authors gratefully acknowledge the help 
Cowley, former director of the Texas A&M University I
tural Research and Extension Center at Weslaco. I

LITERATURE CITED

1. Amemiya, M., L. N. Namken, and C. l. Gerard. 1*
water depletion by irrigated cotton as influenced by water ‘_
stage of plant development. Agron. l. 55:376-379. I

2. Bloodworth, M. E., C. A. Burleson, and W. R. C I,
Root distribution of some irrigated crops using undisturbed
Agron. 1. 50:317-320. I ’

3. Burleson, C. A., M. E. Bloodworth, and l. W. p;
Effect of subsoiling and deepfertilization on the growth,
bution and yield of cotton. Texas Agr. Exp. Sta. PR-1992.

4. Burleson, C. A., W. R. Cowley, and A. D. Dacus.
tilizing grain sorghum in Lower Rio Crande Valley. Tex
Sta. MP-362. a

5. Brown, K. W., C. l. Gerard, B. W. Hipp, and l.
1974. A procedure for placing large undisturbed monolith;
ers. Soil Sci. Soc. Amer. Proc. 38:981-983. 

6. Danielson, R. E. 1967. Root systems in relation toi
390-413. In Agron. Monogr. No. 11, Irrigation of agric 
(Edited by R. M. Hagan and others). l “

——-— MEDIUM-TEXTURED sonn. 
—x- FINE-TEXTURED SOIL

 

 

_i.i'/
1/.
~/
-/
o/
_ x
.?x X—-X-———x—-x——-x-—x——-x—x--""xr%x
_?X

X Figure 24. Growth on non-

I I l I I I I l l _ l . _ L irrigated cane as influenced
no so no so no so no so no so no so no so by soil properties during

APRIL MAY JUNE JULY AUG. SEPT. OCT. 1974, a dry year.
—-— MEDIUM-TEXTURED sou. .
0/
__x- FINE-TEXTURED SOIL /
0/./.
/ gxkx
/ x/
n 
x2
xz.
/./
/x

‘(Fa a Figure 25. Growth of

l l l . I l I l I furrow-irrigated cane as in-

no so n10 so no so no so no so no so no so fluenCed bY 50" Properties

APRIL MAY JUNE JULY AUG. SEPT. OCT. in 1974, a dry year.
/X}
——-—— MEDIUM-TEXTURED sou. --—-- x
,}x?)(}
—-x— FINE-TEXTURED sonn. .2
2' x-"X

f)‘ Figure 26. Growth of sugar-

X cane drip-irrigated at 125

l I _ i l _ l 1 _ l _ l l percent pan evaporation as

no so no so no so no so no so no so no so influeniied by $0" PFOP-
APRIL MAY JUNE JULY AUG. SEPT. oer, erties in 1974, a dry year-

21

Figure 27. Root development of NCO 310
cane drip-irrigated at 125 percent pan
evaporation as influenced by soil prop-
erties in 1974, a dry year.

0-6
6-l2
U)
LU
I
O
Z
__ l2-24
I
l-
O.
LU
Q -
24-36
Figure 28. Soil salinity of
furrow-irrigated cane in
mmhos/cm at different
depths and locations with
respect to cane plants and 36-48

soil properties in 1974, a
dry year.

22

I

I

I

i2.0 —
_________.
i0.0 - .2

n? /

\ 

2 

d: PE RMEA 

g x/ “X- i;

c) X/ _ ‘-

+5 4.0 - /

o ________ ___---0

0: x 0/20 0

2.0 - 0
1 l l l
I 2 3 4 i: -.
SOIL DEPTH - FT.
is" i2" i2" I2"
.A*————* *-—-+C*~——-*
B D

I 2 I 3 l.5 I 4 i5 |_4

I 2 l.O l 5 ll L2 |_5
I 2 l.5 IO I i l.6 l.8

i0 I.2 I 2 0.9 3.4 3.0 it
l.O l.I l.4 0.9 e0 0.0 

MEDIUM —-TEXTURED SOIL

F|NE—TEXT Q

  

  
   
   
   
 
 
  
  
  
   
 

 Gerard, C. J., and S. A. Reeves. 1975. Influence of climatic
p’ ions and moisture levels on earliness and yield of different cot-
 ltivars on irrigated vertisols. Proc. Beltwide Cotton Prod. Res.
s’ p 76-78.

 Gerard, C. J., and S. A. Reeves. 1975. Influences of N and
population on earliness and yields of early maturing cotton cul-
igrown on irrigated vertisols. Proc. Beltwide Cotton Prod. Res.
p. 78-80.

 Gerard, C. J., and L. N. Namken. 1966. Influence of soil tex-
If; >0 rainfall on response ofcotton to moisture regime. Agron. J.

‘*2.

i). Gerard, c. J., B. w. Hipp, |<. w. Brown, o. w. DeMichele,

* Sharpe. 1974. An investigation of the return flow from irrigated

 apt. 2., Texas Water Resources Inst. TR-60. 84 p.

 Gerard, C. J., and S. A. Reeves. 1974. Influence of climatic

81¢ ns, soils and management on performance of different cotton

fjProc. Beltwide Cotton Prod. Res. Conf. p. 77-78.

 Gerard, C.J., B. W. Hipp, and W. R. Cowley. 1971.

és-irrigation-spacing-blossom-end rot. Texas Agr. Exp. Sta.

. 19 p.

13. Gerard, C. J., and B. W. Hipp. 1968. Blossom-end rot of
Chico and Chico Grande tomatoes. Proc. Amer. Soc. Hort. Sci.
93:521-531.

14. Gerard, C. l. 1974. Use of tensiometers and pan evaporation
to irrigate sugarcane. Texas Agr. Exp. Sta. Tech. Rep. No. 74-2. 18 p.

15. Gerard, C.J., and B. W. Hipp. 1975. Irrigation and soil
studies on sugarcane. Texas Agr. Exp. Sta. Tech. Rep. No. 75-2. 5O p.

16. Kramer, P. J., O. Biddulph, and F. S. Nakayama. 1967. Water
absorption, conduction and transpiration. In Agron. Monogr. No. 11,

p. 320-329. Irrigation of Agricultural Lands (Edited by R. M. Hagan
and others).

17. Maletic, J. T., and T. B. Hutchings. 1967. Selection and
classification of irrigated land. In Agron. Monogr. No. 11, p. 125-156.
Irrigation of Agricultural Lands (Edited by R. M. Hagan and others).

18. Taylor, S. A., and J. L. Haddock. 1956. Soil moisture availa-
bility related to power requirement to remove water. Soil Sci. Soc.
Amer. Proc. 20:284-288.

19. Vazquez, R., and S. A. Taylor. 1958. Simulated root distribu-

tion and water removal rates from moist soil. Soil Sci. Soc. Amer. Proc.
22:106-1 10.

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ZAll programs and information of The Texas Agricultural Experiment
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23

2M-1-77
Texas Agricultural Experiment Station
J. E. Miller, Director
A College Station, Texas