OAKTrust Digital Repository (Texas A&M Univ)

Ketchersid, Mary L.

Baumann, Paul A.

Protecting the Environment, Using Integrated Weed Management in Lawns

Redmon, Larry A.

Stockpiling Bermudagrass or Bahiagrass for Fall/Winter Grazing

Maeda, Murilo

Bell, Jourdan

Wright, Robert

Keeling, Wayne

2018 Texas High Plains and Panhandle Replicated Agronomic Cotton Evaulation (RACE) Trials

Miller, Travis D.

Ryegrass Most Damaging Weed in Winter Wheat

Stevenson, Douglass E.

Baumann, Paul

Jackman, John A.

Pesticide Properties that Affect Water Quality

McAfee, James A.

 
 
 James A. McAfee, Ph.D. 
Associate Professor and Extension Turfgrass Specialist  
Texas AgriLife Extension Service,  Dallas,  Texas 
 
Managing Sports Fields in Drought/Adverse Conditions 
Figure 1: Bermudagrass stressed from lack of 
irrigation during drought stressed conditions 
According to the US Drought Monitor, at the 
end of July 2011, 99% of Texas is at one level of 
drought or another. This coupled with triple 
digit temperatures has placed a huge stress on 
available water supplies throughout the state of 
Texas.  Most areas of the state have initiated 
restrictions on number of irrigations per week 
for turfgrass/landscape and in some cases water 
for outdoor use has been banned. 
 
In the past few years, dealing with water 
restrictions for sports fields as well as other 
turfgrass sites has become a common event.  
Drier than normal weather conditions along 
with increased population growth in Texas over 
the past 10 years has created problems with 
water supplies in different areas of the state. It 
has become normal for many high schools, city 
parks and even colleges to have the amount of 
water available for their sports fields either 
severely reduced during summer months or in 
some cases completely turned off (see Figure 1).  
This article will discuss the different levels 
(stages) of water restrictions, managing sports 
fields to prepare them for drought/adverse 
weather conditions and discuss how to 
properly manage a sports field during 
drought conditions. 
 
Understanding water restriction regulations 
can often be very confusing.  In Texas, water 
allocations are controlled by different water 
districts throughout the state. These water 
districts will sell a certain amount of water 
each year to its different constituents in the 
water district such as cities. The amount of 
water provided to each constituent is usually 
 
 
2 
Donec sit amet arcu. 
Stage 1: Mild (voluntary restrictions). 
 
1. Stage 1 is strictly a voluntary restriction on outdoor use of water. 
2. The purpose of Stage 1 is to raise the public’s awareness of a water shortage problem. 
3. In some cases, cities may restrict the amount of water available for outdoor use to 
government facilities. 
Stage 2: Moderate (mandatory restrictions). 
 
1. The goal of stage 2 ––restrictions is to reach a 2% reduction in water use. 
2. Generally, watering is limited to after 6:00 pm in the evening and before 8:00 am in the 
morning. 
 
3. Cities will also generally limit irrigation to twice per week during stage 2. 
Stage 3: Severe (mandatory restrictions). 
 
1. The goal of stage 3 is to reduce water use by 5%. 
2. Generally, irrigation is limited to one time per week. 
3. As in stage 2, hours for irrigation are limited to after 6:00 pm and befo e 8: 00 am. 
4. In stage 3, hand watering of landscapes is still allowed. 
Stage 4: Emergency (mandatory restrictions). 
 
1. The goal of stage 4 restrictions is to reduce water use by 10%. 
2. Basically, all outdoor use of water is prohibited. 
3. In some cases, the use of hand watering for foundations is still allowed. 
 
based on previous usage (averages) along with 
predicted growth demands. The water district 
is usually the authority that determines when 
the different stages (levels) of water 
restrictions will occur, which is based on 
water availability. Note, in some cases the 
cities will determine their own water 
restriction guidelines in order to conserve 
available water. The cities will determine how 
they will meet the reduced available water by 
restricting the number of days individuals can 
water and the time of day they can water. 
Generally, it is the water districts 
determination as to when the water 
restrictions will be removed.  It is important 
to understand the different levels of water 
restrictions in your area and what they 
mean. Outlined below is a list of the 
different stages of water restrictions used in 
Texas.  While these stages or level of water 
restriction may vary in different areas of the 
state, level of water restrictions are pretty 
similar. 
 
 
3 
 Understanding these different stages of 
water restriction will allow the sports field 
manager to best determine the level of 
management practices to use on their fields.  
During stage 1 and 2 restrictions, continue 
to use best management practices such as 
fertilization, mowing, irrigation and 
aerification to produce as healthy a stand of 
turfgrass as possible for the field. This is the 
time to prepare the turfgrass on the sports 
fields to better survive an extended 
restriction of water for use on their fields.  
If stage 3 restriction is imposed, then 
reduce the amount of fertilization, 
especially nitrogen for the turfgrass.  
Forcing excess growth during drought 
conditions will only make the situation 
worse. Slightly raise the height of mowing 
during stage 3 to help relieve some of the 
stress on the grass. However, always stay 
within the range of recommended mowing 
height for the particular turfgrass being 
grown on the sports field. Do not mow 
fields if grass is showing signs of moisture 
stress. As long as adequate soil moisture is 
still available, continue to aerify the fields 
at normally scheduled times for 
aerification. Apply herbicides for weed 
control with caution during stage 3, since 
Table 1. Recommended Rates of Nitrogen for Turfgrasses Grown on Sports Fields 
Turfgrass                                                                                      Nitrogen 
                                                                                                Lbs. N/1,000 sq.ft./year 
 
Common bermudagrass      5 to 6 
Hybrid bermudagrass      6 to 8 
Zoysiagrass        3 to 4 
Seashore paspalum       2 to 3 
Kentucky bluegrass       3 to 6 
Tall fescue         4 to 7 
turfgrasses under moisture stress are 
more subject to injury from herbicide 
applications.  At stage 4, then discontinue 
the application of any fertilizer to the fields 
unless adequate rainfall occurs. Also, 
discontinue mowing the fields at the stage 4 
level of water restrictions. Turfgrass injury 
can occur when fields are being mowed 
during extended drought conditions. 
 
As long as adequate moisture is available, 
continue to fertilize the fields with 
recommended rates of nitrogen.  Table 1 
contains the recommended rates of nitrogen 
for the different turfgrasses used on sports 
fields in high schools and city parks. Once 
water restrictions are imposed, then consider 
reducing the amount of nitrogen on the fields 
and if water is totally cut off, then 
discontinue the application of nitrogen to the 
fields.  It is important to use soil testing to 
make sure all other essential nutrients are 
available for healthy plant growth, especially 
potassium.  Potassium is a key nutrient in 
stress tolerances such as drought. Turfgrass 
plants low in potassium will not be able to 
survive drought conditions as well as plants 
containing adequate levels of potassium. 
 
 
While all cultural 
practices are important 
in producing a dense, 
healthy stand of 
turfgrass on sports 
fields, mowing is one of 
the most important (see 
Figure 2). As long as 
supplemental irrigation 
is available, continue 
to mow the field at the 
recommended height 
and frequency for the 
turfgrass on your 
field.  See Table 2 for 
recommended mowing height of 
different turfgrasses used for sports fields.  The 
key is to mow often enough so that you never 
remove more than 30 to 40% of the leaf blade.  
Removal of excess leaf tissue will place an 
additional stress on the turfgrass. Once 
supplemental irrigation is restricted, then raise 
the height of cut on the field to the upper end of 
the recommended mowing height for the type 
of turfgrass on your field. For example, the 
recommended mowing height for hybrid 
bermudagrass is 0.5 to 1.0 inch.  During water 
Table 2.  Recommended Mowing Height for Turfgrasses Used on Sports Fields 
 
Turfgrass                                                                                      Mowing Height (inches) 
 
Common bermudagrass       1.0 to 1.5 
Hybrid bermudagrass       0.5 to 1.0 
Zoysiagrass                                                                                                0.75 to 1.5 
SeaShore paspalum        0.5 to 1.0 
Kentucky bluegrass        1.5 to 2.5 
Tall fescue         1.5 to 3.0 
Figure 2:  Proper mowing is one of the key cultural practices in developing a dense, healthy stand of turfgrass on a sports field.  The healthier the turfgrass, the better able it can survive extended drought conditions. 
restrictions, raise the height of cut to 1.0 to 
1.5 inches. Mowing the hybrid bermudagrass 
at 2 to 3 inches will not save water and this 
height of cut will produce a thin, open stand 
of bermudagrass that is easily worn out once 
play starts on the field. Keep mower blades 
sharpened to provide a good clean cut of leaf 
tissue.  Dull mower blades will shred or tear 
end of the leaf blades, thus adding an 
additional stress to the turfgrass plants. 
 
 
5 
 As long as water is not 
restricted, continue to irrigate fields deeply and 
as infrequently as possible. Deep, infrequent 
watering will encourage a deeper more 
extensive root system. Frequency of irrigation 
and amount of supplemental water applied per 
irrigation cycle will be determined by soil type, 
turfgrass, irrigation system and use of the field.  
It is important to run an irrigation audit on the 
irrigation system to insure that supplemental 
water is being applied as uniformly as possible 
and that you are only applying the 
necessary amount of water required 
for healthy plant growth (see Figure 
3). Most water restrictions allow a 
once per week schedule for irrigation.  
A once per week irrigation schedule 
makes it difficult to apply enough 
water on one field, but makes it 
impossible to apply enough water 
when you are talking about watering 
large sports field complexes that 
cover 30 to 40 acres. During 2006, 
many city parks and school districts 
were able to lobby for a variance on these large 
complexes with the water authorities by 
showing that they had conducted an irrigation 
audit on their systems and that they were only 
applying the necessary amount of water needed 
for their fields. A considerable amount of 
irrigation water is lost through run-off, 
especially on fields with a crown.  To help 
reduce water loss from run-off, use the cycle and 
soak method for irrigating the fields.  For this to 
work, you must first observe the different zones 
Figure 3:  Conduct 
irrigation audit to make 
sure irrigation system is 
working as efficiently 
as possible.  Darker 
green  bermudagrass 
was due to irrigation 
head not rotating. 
Figure 4: During severe drought conditions either 
discontinue watering areas not in play or water 
occasionally to keep grass alive. 
 
 
6 
to see how long it takes before run-off starts 
occurring. Then monitor the site to see how long 
it takes for the water to soak into the soil profile.  
If run-off occurs in 15 minutes, then set the 
station to run for 15 minutes and then come 
back later and apply a second application of 15 
minutes.  If you need more water, then do a 
third cycle at 15 minutes. Note, there will be 
limitations to this cycle and soak method if you 
can only water your fields once per week and 
you have multiply fields at the complex.  
Another way to save water during extended 
drought periods is to only water areas of a large 
complex that are in play (see Figure 4). 
 
Aerification is an important tool that can be 
used to prevent or control soil compaction on 
sports fields. As long as adequate soil moisture is 
available, continue to aerify your sports fields on 
your regular scheduled basis. However, once 
irrigation is restricted or completely eliminated, 
then discontinue aerifying the fields.   
 
One of the most difficult things to manage 
during drought conditions is field use. While 
managing field use is an extremely difficult job, 
if the drought continues and supplemental 
irrigation is severely reduced  
or eliminated, then restricting the amount of 
play (events) on your sports fields will become 
critical. Continued use, especially excess use, of 
sports fields during drought conditions will 
result in the loss of turfgrass on these fields.  The 
amount of turfgrass loss will be determined by 
the amount of play as well as the length of the 
drought conditions. Individuals in charge of 
scheduling play on your sports fields need to be 
fully aware of this potential loss as well as 
understand the cost involved in reestablishing 
turfgrass back on the fields once the drought is 
over. Another issue that needs to be fully 
considered is player safety. The majority of 
sports fields at city parks and school districts are 
constructed using native soils that are often high 
in clay and/or silt content.  Once these fields 
become dry, not only do they become very hard, 
but they also tend to form cracks in the playing 
surface (see Figure 5). Hard, compacted surfaces 
increase potential for player injury, especially 
head injuries, while cracked soils increase the 
potential for ankle and knee injuries to the 
players.   
 
While using the practices outlined above may 
not prevent the loss of turfgrass on your sports 
fields during extended drought 
conditions, if watering is 
eliminated, they will provide 
the best possible chance for 
keeping as much turfgrass 
alive as possible during the 
drought conditions.  
Figure 5:  Cracking of soils 
during drought conditions.  
This creates unsafe playing 
conditions for players. 
 
 
 
7 
 
Key steps for managing sports fields during drought conditions: 
 
1. Do an irrigation audit on your irrigation system to make sure it is operating as efficiently 
as possible.  Fix any problems that are noticed during the audit.  Use the cycle and soak 
method to reduce loss of water from surface run-off. 
2. Reduce fertilizer applications, especially nitrogen during drought conditions.  If stage 4 is 
imposed, discontinue application of any fertilizer. 
3. Raise mowing height during drought conditions and if stage 4 is initiated, discontinue 
mowing the fields. 
4. Restrict use of the fields.  Eliminating or reducing use of fields may mean revenue loss, 
which is tough to do.  However, in the long run how much will it cost in loss revenue and 
expense to redo the field if the grass dies from over use in drought conditions. 
5. Do not allow unofficial play on the field(s).  This may mean having cities pass an 
ordinance to fine individuals who use the field without permission. 
6. Apply herbicides with caution. If moisture is available, then it is possible to apply some 
weed control.  However, in stage 4, discontinue use of herbicides. 
7. Monitor turfgrass for any insect and/or disease problems.  There are very few diseases or 
insects that will occur in these conditions, but it can happen.  If disease/insect activity is 
present during drought and you do not control them, the loss of turfgrass on the fields will 
be increased. 
8. Get to know the water district personal that supply water to your district.  Let them know 
what you are doing to conserve water (audits, fixing irrigation problems, etc.).   
For questions or additional information contact: 
Dr. Jim McAfee 
Associate Professor and Extension Turfgrass Specialist 
j-mcafee@tamu.edu 
 
 
8 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
                       Produced by the Department of Soil and Crop Sciences 
 
 
 
 
 
 
 
 
 
 
 
 
  
 
 
 
 
 
 
 
The information given herein is for educational purposes only. Reference to commercial products or trade names is made with the                  
understanding that no discrimination is intended and no endorsement by the Texas AgriLife Extension Service is implied. 
 
 
 
 
 
 
 
 
Educational programs of the Texas AgriLife Extension Service are open to all people without regard to race, color, sex, disability, 
religion, age, or national origin. The Texas A&M University System, U.S. Department of Agriculture and County Commissioners 
Courts of Texas Cooperating. 
 
Issued in furtherance of Cooperative Extension Work in Agriculture and Home Economics, Acts of Congress of May 8, 1914, as 
amended, and June 30, 1914, in cooperation with the United States Department of Agriculture, Edward G. Smith, Director, Texas 
AgriLife Extension Service, Texas A&M System. 


Managing Sports Fields in Drought/Adverse Conditions

Schnell, Ronnie

McGinty, Josh

Livington, Clint

2015 Uniform Corn Hybrid Trials

Taylor, Gene R., II

Gray, Jason

Gene R. Taylor II, Assistant Professor and Extension Turfgrass Specialist
Jason Gray, Extension Assistant—Turfgrass Management
The Texas A&M University System
Maintaining
St. Augustinegrass
L a w n s
L-5340
11/99
St. Augustinegrass (Stenotaphrum secundatum [Walt.]
Kuntze) is a popular warm-season turfgrass for home lawns.
It is found in the United States, southern Mexico, South
America, South Africa, western Africa, the Caribbean, the
Hawaiian Islands, Australia and the South Pacific.
St. Augustinegrass is medium to dark green and coarse
textured, and it has a low, dense growth habit. It grows well
in nearly all soil types and tolerates shade, heat, salt and, to
some degree, drought. It does not tolerate waterlogged soils
or extended periods of cold weather. St. Augustinegrass is an
aggressive species that spreads rapidly by above-ground
growth structures called stolons. If managed properly, St.
Augustinegrass forms a dense cover that handles light traffic
and competes well with most weeds. St. Augustinegrass is
the most shade tolerant warm-season turfgrass.
Texas Common, Raleigh, Seville, Palmetto and Floratam
are St. Augustine varieties commonly used for home lawns in
the southern United States. Each variety has characteristics
that make it best in certain situations. Contact your county
Extension agent for information on the variety best suited for
your location.
To keep your St. Augustinegrass lawn in good condition,
follow these guidelines for mowing, watering and fertilizing,
as well as for controlling weeds, insects, thatch, and
eliminating compacted soil. Because many factors affect turf
growth, these are general recommendations.
MARCH through May
Mowing
Begin a routine mowing program as soon as the grass
begins to turn green in the spring. Remove no more than
one-third of the leaf area with any one mowing. Set the
mowing height at 21/2 to 3 inches (3 to 31/2 inches in shady
lawns). The lower the mowing height, the more frequently
you will need to mow. Frequent mowing at a lower height
produces higher quality turfgrass.
It is best not to bag grass clippings. Grass clippings
decompose quickly and return significant amounts of
nutrients to the soil. If you do bag the clippings, consider
composting them for use in the landscape.
Fertilizing
Begin fertilizing 3 weeks after the grass turns green and
when there is little chance of a late frost. Apply 1 pound of
soluble nitrogen per 1,000 square feet of lawn every 8 weeks,
or 11/2 pounds of slow-release nitrogen every 10 weeks.
Have your soil tested to determine what added nutrients
your lawn may need. For information on soil testing
procedures, contact your county Extension agent.
If you do not have the soil tested, use a complete fertilizer
with a 3-1-2 ratio of nitrogen, phosphorus and potassium
(Examples: 15-5-10, 21-7-14, etc. Every bag of fertilizer has
the nutritional analysis printed on the bag).
To determine the amount of fertilizer needed to equal 1
pound of nitrogen per 1,000 square feet, divide 100 by the
first number in the fertilizer analysis. For example, if you
are using a 15-5-10 fertilizer, then you need 6.6 pounds per
1,000 square feet. (To determine the amount needed to apply
11/2 pounds per 1,000 square feet, substitute 150 for 100.)
100  15 = 6.6
Then determine the size of the area to be fertilized. If
your lawn is 5,000 square feet, you will need 33 pounds of
15-5-10 fertilizer.
(5,000  1,000) x 6.6 = 33 pounds of fertilizer
Watering
To keep your lawn healthy, water it only when the grass
needs it. When you do water, wet the soil to a depth of 6
inches. Then don’t water again until the grass shows
symptoms of drought stress—a dull, bluish color, rolled or
folded leaves, and persistent footprints. This usually occurs
in 5 to 10 days, depending on the weather.
Follow these steps to determine how long to water to
apply the right amount.
1. Set out five or six open-top cans randomly around the 
lawn (tuna or cat food cans work best).
2. Turn on the sprinklers or irrigation system for 30 minutes.
3. Using a ruler, measure the depth of water caught in each 
individual can, and record the depths.
4. Calculate the average depth of water of all the cans.
Example: You have placed five cans in your yard. The 
depths of water in the cans were 0.5 inch, 0.4 inch, 0.6 
inch, 0.4 inch and 0.6 inch. Add the depths together and 
divide by the number of cans you used.
0.5 + 0.4 + 0.6 + 0.4 + 0.6 = 2.5 inches
2.5 inches  5 cans = 0.5 inch of water in 30 minutes
New-style irrigation controllers allow you to water several 
times a day, so you can program them to prevent run-off.
5. Use a garden spade or a soil probe to find out how deeply 
the soil was wet during the 30-minute period. The probe 
will push through wet soil easily, but it is more difficult 
to push through dry soil.
With proper maintenance, you can help keep
your St. Augustinegrass lawn healthy and attractive. 
St. Augustinegrass spreads by above-ground growth structures called stolons.
6. When you know how much water was 
applied in 30 minutes and how deeply that 
volume of water wet the soil, then determine 
how long you must water to wet the soil to a 
depth of 6 inches.
Example: If the sprinklers sprayed 1/2 inch of 
water in 30 minutes and wet the soil to a 
depth of 3 inches, you would need to apply 1 
inch of water to wet the soil to a depth of 6 
inches. To do so you must water for 1 hour.
Run-off from watering a lawn can waste a
significant amount of water, which is costly and
a poor use of a limited natural resource. The
factors determining how quickly run-off occurs
are the type of soil and the application rate of
the sprinkler system. Do not apply water faster
than the soil can absorb it. To prevent run-off:
1. Check the lawn while watering. If water 
begins running into the streets or gutters, 
note how long it took before run-off 
occurred. This is the maximum amount of 
time you should water at one time.
2. Stop watering and allow the soil surface to 
dry (30 minutes to 1 hour).
3. Begin watering again and continue for the 
time you’ve determined. With an automatic
irrigation system, change your timer to the 
new, shorter time.
4. Continue this cycle until the appropriate 
amount of water has been applied to wet the 
soil to a depth of 6 inches.
Controlling weeds
The best form of weed control is a healthy,
dense, actively growing lawn. To control
crabgrass and other grassy weeds, apply
preemergent herbicides (which control weeds
before they sprout from the ground) in the
spring when soil temperature reaches 65 ºF or
when the redbud and dogwood trees begin to
bloom. Apply postemergent herbicides (which
control weeds that have already sprouted) as
needed. Apply herbicides only when weeds are
present, and when the grass is healthy and
actively growing.
Weed control is most effective if you apply
the herbicide when the weeds are still very small.
St. Augustinegrass is very sensitive to some
herbicides, such as 2,4-D. Read the label
carefully before applying any herbicide to ensure
that it is the right product for the weeds you have
and that you do not damage the turf. Follow all
instructions on the label. It explains how and
when to use the product and how much to apply.
Controlling insects
Chinch bugs and white grubs are the two
most serious insect pests in St. Augustinegrass
lawns. Routinely check for these pests and treat
as necessary. (See L-1766, “Chinch Bugs in St.
Augustine Lawns,” and L-1131, “White Grubs
in Texas Turfgrass,” available from the Texas
Agricultural Extension Service.)
Controlling thatch
If the thatch layer (a layer of undecomposed
plant matter) is more than 3/4 inch thick, mow
the lawn with a vertical mower or scalp the
lawn (cut with a rotary mower at its lowest
setting) in April or May when the grass is
healthy and actively growing.
Eliminating compacted soil
In areas of heavy traffic, aeration can help
eliminate compacted soils. Use a core-aerating
machine when the grass is actively growing. If
you have an underground irrigation system, flag
the sprinkler heads first to avoid damaging them.
JUNE through September
Mowing
Follow the same recommendations as for
March through May.
Fertilizing
Continue the fertilizer program begun in the
spring, applying 1 to 11/2 pounds of nitrogen per
1,000 square feet every 8 to 10 weeks. Without
soil test information, it is recommended that
you use a fertilizer that either contains nitrogen
only (21-0-0, ammonium sulfate) or is low in
phosphorus (Examples: 21-3-6 or 15-0-15) to
reduce the chance of excessive phosphorus
Frequent mowing at a low mowing height produces a higher
quality turfgrass.
Produced by Agricultural Communications, The Texas A&M University System
Extension publications can be found on the Web at: http://agpublications.tamu.edu
Educational programs of the Texas Agricultural Extension Service are open to all people without regard to race, color, sex, disability, religion, age or national origin.
Issued in furtherance of Cooperative Extension Work in Agriculture and Home Economics, Acts of Congress of May 8, 1914, as amended, and June 30, 1914,
in cooperation with the United States Department of Agriculture. Chester P. Fehlis, Deputy Director, Texas Agricultural Extension Service, The Texas A&M
University System.
5 M, New TURF 4
build-up in the soil. Such build-ups can lead to deficiencies
in iron and zinc.
To prevent yellowing caused by iron chlorosis, apply
liquid or granular iron fertilizer throughout the growing
season. Follow the label directions for the rate of appli-
cation. Fertilizers containing iron may stain concrete, brick
or stone surfaces.
Watering
Follow the same recommendations as for March through
May.
Controlling weeds
Continue applying postemergent herbicide as needed.
Herbicides containing 2,4-D should be used with care, as St.
Augustinegrass is sensitive to this herbicide. Herbicides may
damage the lawn if you apply them when the temperature is
higher than 90 ºF.
Controlling insects
Follow the same recommendations as for March through
May. The most effective time to treat for white grubs is in
August when they are immature and close to the soil surface.
Eliminating compacted soils
Follow the same recommendations as for March through
May.
SEPTEMBER through February
Mowing
Continue the recommended mowing practices until the
grass goes dormant and does not require mowing.
Fertilizing
Continue fertilizing as recommended until 4 to 6 weeks
before the first expected frost. At that time, apply a low
nitrogen, high-potassium fertilizer such as 5-10-10. Apply
no more than 1/2 pound of nitrogen per 1,000 square feet. To
calculate the amount of product needed per 1,000 square
feet, substitute 50 for 100 in the spring formula.
Do not fertilize St. Augustinegrass from December
through February unless the lawn has been overseeded
(planted with cool-season grass to maintain its green color
in the winter). Fertilize overseeded lawns once in December
and again in February with 1/2 pound of nitrogen per 1,000
square feet, using a nitrogen-only fertilizer such as 21-0-0. 
Have the soil tested to determine the nutrients needed. In
the absence of a soil test, use a complete fertilizer with a 3-
1-2 ratio of nitrogen, phosphorus and potassium. 
Watering
Even though St. Augustinegrass is normally dormant in
winter, you may still need to water it periodically when the
weather is warm, dry and windy. If the lawn has been
overseeded, water as you would from March through May.
Controlling weeds
Apply preemergent herbicides for annual winter weeds
when the average soil temperature drops to 70 ºF. Your
county Extension agent can give you an estimate of that date
in your area. Apply postemergent herbicides as needed.
Controlling insects
St. Augustinegrass lawns should experience no detrimental
insect activity during the winter.
If managed properly, St. Augustinegrass forms a dense cover that handles
light traffic well.
The information given herein is for educational purposes only. Reference to trade names is made with the understanding 
that no discrimination is intended and no endorsement by the Texas Agricultural Extension Service is implied.
For more information,
see the Web site at
http://aggieturf.tamu.edu.


Maintaining St. Augustine Grass Lawns

Lemon, Robert G.

McFarland, Mark L.

Tuggle, Justin C.

Henning, Ron J.

Danheim, Chuck

Influence of Irrigation Water Quality and Quantity on
 Peanut Production in the Texas High Plains
Robert G. Lemon1, Mark L. McFarland1, 
Justin C. Tuggle2, Ron J. Henning2, and Chuck Danheim2
ABSTRACT
The Southern High Plains of Texas experienced a significant influx of peanut acreage over the past
three years.  Much of the new   acreage and increased interest in peanut production is  associated with
cross-county transfer and cropping flexibility provisions of the 1996 Farm Bill.  In 1998, more than
190,000 acres of peanut were planted in the area, which comprises about 14 counties.  Because of the
dependence on irrigation in this semi-arid  region, water quantity and quality are  constant concerns.  Texas
experienced a severe drought in 1998, during which  many producers encountered moderate to severe
problems with well capacities and water quality.  This  study was implemented  to assess the influence of
water quantity and quality on peanut yield and grade.   Soil and water samples were obtained from 36 fields
in Dawson and Terry counties at the beginning and  end of the growing season, and subjected to detailed
salinity analyses.  
                                                 
1Associate Professor and Extension Agronomist, and Associate Professor and Soil Fertility Specialist,
Texas Agricultural Extension Service, College Station, TX 77843-2474, and 2Technical Service Providers,
DeLeon Peanut Company, Lamesa, TX 79331.
2
NC-7 (virginia market type)  was the variety at all  locations. Yield and grade data were obtained from
each site.  Regression analyses  indicated boron in irrigation water and the soil sodium adsorption ratio
(SAR) were  negatively correlated with yield.   Boron levels  greater than 0.75 ppm and soil  SAR values
greater than 5 caused  appreciable yield reduction.   Peanut quality also was assessed and chloride and
water salinity both correlated with reduced grades.  Chloride levels in irrigation water above  450 ppm
significantly reduced grades as did salinity values exceeding 2,100 umhos/cm.  Well capacity also was
categorized and results  indicate  that for optimum peanut yield (yield goal of 5,000 lbs./acre), wells must
have a minimum capacity of approximately  4.5 to 5.0 gallons/minute/acre. 
INTRODUCTION
The Southern High Plains of Texas has experienced a significant influx of peanut acreage over the
past four years.  Much of this increased acreage and interest in peanut production  has been associated with
the cross-county transfer and cropping flexibility provisions of the 1996 Farm Bill.  From  1995 to 1998,
peanut acreage in the  region increased from  44,000 to more than 190,000 acres were reported in an 18
county area (Texas Agricultural Statistics, 1995 and 1998).  Peanut production from the region represents
approximately  57% of  total statewide production.    The west Texas region is characterized as a semi-arid
environment with average annual rainfall of 18 to 22 inches.  Extreme summer temperatures coupled with
high winds contribute to excessive evapotranspiration rates. 
Because of the dependence on irrigation in the region, water quantity and quality are a constant
concern.   Marginal quality irrigation water  is becoming a problem throughout many areas of Texas, but
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especially the High Plains region.   Three primary factors affect water quality: total soluble salts (salinity),
sodium hazard (SAR), and toxic ions (chloride, sulfate, sodium and boron).  The susceptibility of crops to
marginal quality water  varies,  with cotton exhibiting significantly   more tolerance to salinity and toxic ions
than either corn or grain sorghum  (USDA, Handbook 60).  Literature regarding water quality effects on
peanut is extremely limited.   Greenhouse experiments conducted in  Israel indicated that yield of peanut
grown in artificially salinized  plots was reduced to 50% at EC of 4.7 mmhos/cm, and 20% at EC of 3.8
mmhos/cm.  (Shalhevet et al., 1969).  Boron fertility studies conducted by  McGill and Bergeaux (1966),
and  Morrill et al. (1977)  indicated sensitivity of peanut to excess soil boron, with a  range of  0.6 to 1.5
kg B/ha resulting in  reduced yields and potential toxicity.
     Due to the rapid  increase in  peanut acreage in west Texas,  and the need to maintain proper
crop rotation, many producers are utilizing moderately productive farmland.   Field observations during the
1997 season showed  peanut to be  extremely sensitive to marginal quality irrigation water (Lemon, 1997).
This study was initiated  to assess the influence of water quantity and quality on peanut yield and grade in
the Texas High Plains.    
MATERIALS AND METHODS
A study of  36 field sites was  conducted in 1998 in Dawson and Terry County, Texas to initiate
an assessment of the influence of  irrigation water quality and quantity on yield and grade of peanut.  Soil
and water samples were obtained from each location   at the beginning  and  end of the season.  Initial
samples were collected in June and final samples were collected in October or November, depending on
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harvest date. 
Water samples represented water entering the pivot.  It is common to have one to four wells
comprising a system, thus samples were collected  at the pivot point after the system had been flushed for
one hour.  Water samples were collected in sterile plastic bottles.   Samples were analyzed within two days
of collection at the Texas Agricultural Extension Service Soil, Water and Forage Testing Laboratory in
College Station, TX.   The irrigation water analysis included soluble cations (Ca, Mg, Na, K), soluble
anions (B, Cl, SO4, NO3), pH, and electrical conductivity (EC).
Soils represented the Amarillo series, and consisted of Amarillo fine sandy loam  (fine-loamy,
mixed, thermic Aridic Palenstalfs), and Amarillo loamy fine sand  (fine-loamy, mixed, thermic Aridic
Palenstalfs) intergrades.  These soils have less than 0.5% organic matter and a pH of 7.5 to 7.9.   This
series possesses a significant clay accumulation at 14 to 16 inches deep.  Soil samples were collected from
the surface 6 inches   according to Texas Agricultural Extension Service guidelines and analyzed for nutrient
status (N, P, K, Ca, Mg, Na, Zn, Mn, Fe, Cu, S, B).  In addition, samples were subjected to a detailed
salinity analysis utilizing the saturated paste extract to determine soluble cations (Ca, Mg, Na, K) and
anions (Cl, SO4) and electrical conductivity.  
All locations  were planted between the  last week of April and  the first week of May with virginia
market-type  NC-7.   Virginia production in Texas is primarily contract-additionals and shellers specify
NC-7 as the variety.   Fertility,  herbicide and fungicide programs were different across locations, but
followed general Texas Agricultural Extension Service guidelines for west Texas.  Fields were dug and
combined  by the producer or custom harvesting operators.  Across locations,  days from planting to
digging  ranged from 140 to 160 days.   Fields experiencing severe water quality related problems were
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dug early (140 days) to prevent additional pod loss.  
Regression analyses were used to determine relationships between various soil and water
parameters,  and peanut yield and grade.  Multiple regression analyses were performed, but were deemed
inappropriate due to excessive  multicolinearity.     Only significant regressions are presented.   
RESULTS AND DISCUSSION
Soil and water samples were obtained at the beginning and end of the season to assess changes
over time.   Although  some soil and water parameters changed over the season, the initial samples
(obtained in June) exhibited more significant correlations with yield and grade.  Consequently, only the June
sampling was utilized  for analysis.  
Peanut Yield
 Regression analyses  indicated significant yield correlations  associated with boron  in irrigation
water, soil SAR and well capacity.  Peanut yield response to boron in irrigation water is presented in Figure
1.  Yields were negatively correlated with increasing boron concentrations (P<0.001).  Boron
concentrations  ranged from 0.1 to 1.2 mg/l across locations. The regression equation [yield = 5042 -
(2179*boron)] indicated that for each 0.1 mg/l increase in boron concentration, yield was reduced by
approximately 218 lbs./acre.  A clustering of data points at 0.75 mg/l  boron suggested a possible critical
threshold level.   Critical boron levels in irrigation water for cotton and grain sorghum are 3 mg/l, and  2
mg/l for corn (McFarland et al. 1998). 
Similar to boron,  peanut yield was significantly reduced with increasing soil SAR (Fig. 2,
P<0.001).  Sodium adsorption ratios in soil ranged from 0 to 7.5 across the 36 locations.   The critical soil
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SAR value for cotton, grain sorghum and corn is 10 (McFarland et al. 1998).    Based on regression
analysis, for each  one unit increase in SAR, peanut yield was reduced by approximately 374 lbs/acre.  
The sodium adsorption ratio is a calculated value used to express the relative proportion of sodium
compared to calcium and magnesium.   The distribution of data points was clustered between SAR values
of 2.5 to 5.0.  Although limited data points exist beyond the range, the regression suggests that the critical
SAR for peanut may be  less than that for cotton, grain sorghum and corn. 
Peanut producers in the Southern High Plains traditionally set their yield goals in excess of  5,000
lbs/acre.     Well capacity is critical in meeting this goal since peanut is a fully irrigated crop in west Texas.
 Yield was positively correlated with increasing well capacity   (Fig. 3, P<0.006).  Within the study, well
capacities ranged from 2.5 gallons/minute/acre to 7.5 gallons/minute/acre.   Regression analysis indicated
that wells must have a minimum capacity of 4.5 to 5.0 gallons/minute/acre to attain 5,000 lbs/acre yield
goals.  This is especially critical for growing  seasons with  low rainfall,  and/or years with limited antecedent
soil moisture.    Texas was in drought conditions during the spring and summer months of 1998,  and most
irrigation systems could not meet the water demands of the developing peanut crop.
Peanut Grade
Peanut kernel quality was significantly correlated only with irrigation water chloride and total soluble
salt concentrations.  Total sound mature kernels (TSMK) were reduced with increasing chloride in irrigation
water (Fig. 4, P<0.001).  Chloride levels ranged from 100 to 750 mg/l across locations, and peanut grades
ranged from 64 to 76 TSMK.   The EC of the irrigation water which ranged from  600 to 3,000 umhos/cm
across locations also correlated with reduced grades (Fig. 5, P<0.001).    Distribution of the data points
indicated a  critical threshold for  EC of approximately 2,100 umhos/cm, and 400 mg/l for chloride.  Grade
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reductions associated with increasing salinity and chloride may be related to reduced Ca uptake by the
kernels. Increased levels of Na, Cl, Mg and K associated with saline water may have an antagonistic
interaction with soil solution Ca.    Several studies  have reported  the detrimental effects of high
concentrations of K and Mg on peanut kernel quality (Bolhuis and Stubbs, 1955; Hallock and Allison,
1980; Lynd and Ansman, 1989).
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LITERATURE CITED
Bolhuis, G.G., and R.W. Stubbs.  1955.  The influence of calcium and other elements on the fruitification
of the peanut in connection with absorption capacity of its gynophores.  Neth.J. Agric. Sci. 3:220-
237. 
Hallock, D.L.,  and A.H. Allison. 1980.  Effect of three Ca sources applied on peanuts. I. Productivity and
seed quality.  Peanut Sci. 7:19-25.
Lynd, J.Q.,  and T.R. Ansman. 1989.  Effects of phosphorus and calcium with four levels of potassium on
nodule histology, nitrogenase activity, and improved “Spanco” peanut yields.  J. Plant Nutr. 12:65-
84. 
McFarland, M.L., R.G. Lemon, and C.R. Stichler. 1998.  Irrigation Water Quality.  Texas Agric. Ext.
Serv., College Station, TX.  SCS-1998-02.
McGill, J.F.,  and P.J. Bergeaux. 1966.  Boron for peanuts.  Univ. of Georgia, College of Agric. Coop.
Ext. Serv. Peanut Release No. 49. 
Morrill, L.G., W.E. Hill, W.W. Chrudimsky, L.O. Ashlock, L.D. Tripp, B.B. Tucker, and L. Weatherly.
1977.  Boron requirements of spanish peanuts in Oklahoma: Effects on yield and quality and
interaction with other nutrients.  Oklahoma State Univ. Rep. No. MNP-99.
Shalhevet, J., P. Reiniger, and D. Shimshi. 1969. Peanut response to uniform and non-uniform soil salinity.
Agron. J. 61:384-387.
Texas Agricultural Statistics Service.  1995 and 1998. Austin, Texas.
U.S. Salinity Laboratory. 1954.  USDA Handbk. No. 60.
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Influence of Irrigation Water Quality and Quantity on Peanut Production in the Texas High Plains

Harris, B.L.

Hoffman, D.W.

Mazac, F.J., Jr.

Rural Well Water Assessment

Texas A&M University

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