Historic note
 Title Page
 Literature cited

Group Title: Bulletin - University of Florida Florida Cooperative Extension Service ; no. 200
Title: Water requirements of Florida turfgrasses
Full Citation
Permanent Link: http://ufdc.ufl.edu/UF00026380/00001
 Material Information
Title: Water requirements of Florida turfgrasses
Alternate Title: EDIS bulletin 200
Physical Description: Book
Language: English
Creator: Augustin, Bruce J
Publisher: University of Florida Cooperative Extension Service, Institute of Food and Agriculture Sciences, EDIS
Place of Publication: <Gainesville Fla.>
Publication Date: <2000>-
Genre: government publication (state, provincial, terriorial, dependent)   ( marcgt )
bibliography   ( marcgt )
non-fiction   ( marcgt )
Bibliography: Includes bibliographical references.
System Details: Internet access required.
Statement of Responsibility: Bruce J. Augustin.
General Note: At head of title: University of Florida, Cooperative Extension Service, Institute of Food and Agriculture Sciences, EDIS.
General Note: "This document is Bulletin 200, one of a series of the Department of Environmental Horticulture, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida. First printed July 1983. Reviewed March 2000."--Footnote.
General Note: Title from web page viewed on October, 26 2001.
 Record Information
Bibliographic ID: UF00026380
Volume ID: VID00001
Source Institution: University of Florida
Rights Management: All rights reserved by the source institution and holding location.
Resource Identifier: aleph - 002735649
oclc - 48384049
notis - ANL3464

Table of Contents
    Historic note
        Historic note
    Title Page
        Title page
        Page 1
        Page 2
        Page 3
        Page 4
        Page 5
        Page 6
        Page 7
        Page 8
        Page 9
        Page 10
        Page 11
    Literature cited
        Page 12
        Page 13
        Page 14
Full Text


The publications in this collection do
not reflect current scientific knowledge
or recommendations. These texts
represent the historic publishing
record of the Institute for Food and
Agricultural Sciences and should be
used only to trace the historic work of
the Institute and its staff. Current IFAS
research may be found on the
Electronic Data Information Source

site maintained by the Florida
Cooperative Extension Service.

Copyright 2005, Board of Trustees, University
of Florida

/ 3 b Bulletin 200



Florida Cooperative Extension Service
institute of Food and Agricultural Sciences
University of Florida, Gainesvllle
John T. Woeste, Dean for Extension

Water Requirements of
Florida Turfgrasses
Bruce J. Augustin*


Water is an essential component for plant growth. It comprises 80 to 90
percent of the fresh weight of turfgrasses (3). Water provides structure for
plants by turgor pressure in cells which results in plant rigidity and cell elon-
gation. Water plays a fundamental role in plant metabolism, both as part of
many biochemical reactions and as a medium for dissolving organic and in-
organic compounds. Water is also the transport medium for distributing sub-
stances throughout the vascular system of the plant, including nutrients
absorbed by the roots and carbohydrates manufactured in the leaves (12, 15).
Only one percent of the water absorbed by plants is utilized for metabolic
activity. The vast majority of water absorbed is used for transpiration. This
is a plant process in which water is absorbed by the roots, passed through the
vascular system, and exited from the plant via stomata into the atmosphere.
Transpiration helps maintain plant temperatures by cooling through the latent
heat of vaporization. The water absorbed by the plants in the transpiration
process also brings nutrients from the soil into the plant (12, 15).


Evapotranspiration (ET) is a process by which water is transferred to the
atmosphere from vegetative surfaces. ET consists of two components, evap-
oration and transpiration. Evaporation is a physical process by which water
is changed from a liquid to a gaseous state. Evaporation takes place from free
water surfaces such as ponds, streams, wet soil, wet thatch, or wet vege-
tation. Transpiration, the other component of ET, is a plant process of
water loss.

*Extension Turfgrass and Water Specialist, Ornamental Horticulture Department,
Agricultural Research and Education Center Fort Lauderdale, Institute of Food
and Agricultural Sciences, University of Florida.

For most practical purposes it is impossible to separate the evaporation
and transpiration components of water loss from turf surfaces. Therefore, the
term evapotranspiration is usually employed in discussions. Also because the
amount of water used in metabolic activities is negligible, evapotranspiration
can be considered to be the same as consumptive water use by turfgrasses.
The amount of water transferred into the atmosphere by evapotranspira-
tion from turf surfaces is governed by a number of environmental factors.
Radiant energy (sunlight), atmospheric vapor pressure (relative humidity),
temperature, wind, and available soil moisture supply are the controlling ele-
ments (7, 21). The type of warm-season turfgrass and how it is managed con-
tribute only minor differences to the amount of ET if the grass is actively
growing and has sufficient water (4). In fact, large turf areas generally have
similar ET rates compared to that of citrus groves or forests (16). This points
out that the environment (incoming solar energy) is the controlling force, not
plant species, provided there is a continuous canopy or coverage of the soil
surface. Minimal ET rates occur when there are dark, cloudy days with high
relative humidity, low temperatures, and no wind. Maximum ET rates occur
on bright sunny days with low 'relative humidity, high temperatures, and
moderate to high winds. Normally in central and south Florida, May has
the highest ET rates, and December has the lowest ET rates because of
these factors (14).
Measurement of actual consumptive water use is an extensive and labor
intensive task involving the use of lysimeters (21, 23, 29). Few of these fa-
cilities exist for this type of turfgrass water research in the United States.
Studies in Arizona (11), Florida (25), Hawaii (8), and Nevada (27) have
showed similar water usage for bermudagrass under summer conditions.
Studies by Stewart et al. (24, 25) at the Agricultural Research and Edu-
cation Center, Fort Lauderdale, examined several factors affecting the
evapotranspiration of St. Augustinegrass and bermudagrass. Their studies
were conducted over a five-year period using controlled water table lysime-
ters. St. Augustinegrass and bermudagrass had similar evapotranspiration
rates during the studies. Table 1 summarizes the observations of actual turf
water use at Fort Lauderdale.

Potential Evapotranspiration

The concept of potential evapotranspiration has been developed to predict
water requirements of plants based on limited climatic data. Potential evapo-
transpiration (ETP) is defined as the water loss from a continuous surface of
turf which fully shades the ground, exerts little or no resistance to the flow
of water into the atmosphere, and always has an adequate supply of soil water

Table 1. Mean monthly evapotranspiration rates from St. Augustinegrass and ber-
mudagrass sods as observed in research plots at Fort Lauderdale, Florida
(24, 25).
Month Water Use (inches) Month Water Use (inches)
January 2.02 July 4.81
February 2.51 August 4.79
March 3.35 September 3.85
April 4.21 October 3.42
May 5.21 November 2.50
June 4.25 December 1.92
Total 42.84

(6, 21, 31). ETP cannot exceed free water evaporation under the same
weather conditions. Under most circumstances actual evapotranspiration is
less than potential evapotranspiration because one or more of the conditions
in the definition restricts the flow of water into the atmosphere.
Potential evapotranspiration is useful in predicting the water requirements
of turf grown under irrigation. Because the actual on-site measurement of
ET is often impractical or impossible, empirical methods have been devel-
oped to estimate water use. These methods rely on climatic data for predict-
ing water needs on a per day, month, or year basis.
Thornthwaite (26), Penman (19), and Blaney-Criddle (5) methods are
common empirical procedures for calculating potential evapotranspiration.
Numerous other methods have been developed for specific crops and loca-
tions (7, 10). Each of these methods make basic assumptions on the corre-
lation between the climatic data used and how the crop responds under those
conditions used to predict potential evapotranspiration. Formulas vary in
their predictive ability depending on the assumptions and original data used
to derive the empirical equation.
The Thornthwaite equation for predicting ETP utilizes temperature and
daylength data (26). It is a simple method, but has significant errors in short
term prediction. The Blaney-Criddle method uses a comsumptive use coef-
ficient, temperature, and percent daylight to predict monthly ETP (5). This
is a popular method for estimating ETP, and its accuracy depends on the
proper coefficient and light levels. The Penman equation predicts daily ETP
based on net radiation, vapor pressure, and wind speed. This method has
been found to consistently underestimate water loss under conditions of
strong sensible heat advection (20).
For accurate calculation of ETP, it is important to use observed environ-
mental data in the equations. Significant errors can result if estimates or an-
other location's data are used. Some methods require data such as net
radiation, which few facilities have the equipment to measure. When using

equations for estimating ETP in several locations within a wide geographical
region, one should select a method that can be used with data collected from
each location.
McCloud (13) developed an equation for predicting potential evapotrans-
piration, which reflected turfgrass water use under Florida conditions. As
McCloud noted, most formulas tend to underestimate water use when the
mean temperature is over 70' E

McCloud's Formula: ETP = KW(T-32)
where, K = 0.01, W = 1.07, and T = mean temperature in F

In Florida more than half of the months have average temperatures above
70F, and in some locations the monthly mean temperature is above 800F four
months of the year (9). Utilizing Thornthwaite, Penman, or Blaney-Criddle
methods under these conditions can lead to significant underestimation of
potential evapotranspiration.
Figure 1 shows a comparison of the McCloud, Penman, and Thornthwaite
methods of calculating potential evapotranspiration for Miami, Florida. All
methods show similar ETP rates in the winter and early spring where
monthly temperatures are less than 70E As monthly temperatures in late
spring and summer increase above 700F, Penman and Thornthwaite ETP
rates level off, while McCloud ETP rates continue to reflect the increasing
temperatures. Practical experience has shown that irrigation requirements
can approach McCloud's predicted rates if rainfall does not occur at regular
intervals and amounts during the summer. If rains occur on a frequent basis
in amounts less than one inch then irrigation amounts will follow trends sim-
ilar to Table 1 because high humidity and cloud cover reduce ET. Keeping in
mind the definition of potential evapotranspiration and to more accurately
reflect Florida's environmental conditions, McCloud's Formula appears to
be a better predictor of turfgrass water use. When weather monitoring facil-
ities across the state begin collecting environmental parameters, such as net
radiation, relative humidity, cloud cover, or others, then other ETP predicting
methods may prove more suitable.

'Irfgrass Irrigation Systems

Turfgrass in Florida is commonly irrigated with overhead sprinkler sys-
tems. These systems are permanently buried in the soil and consist of sprin-
kler heads, pipes, fittings, valves, and controllers. Numerous differences
exist among sprinkler systems due to differences in manufactured parts, sys-
tem design, and installation. Sophistication and automation of a sprinkler

10 M

o M
c 8-

o M M

CL 6- P T-T

4 /M / M
o M
.4- TZ P\
> P P
w M T T \ p
S 2- T T



Figure 1. A comparison of McCloud (M), Penman (P), and Thornthwaite (T)
methods of calculating potential evapotranspiration for Miami,

system are closely related to the price of installation. Specific details on
sprinkler system design, construction, and operation are given by Watkins
(30) and Sarsfield (22).
Regardless of the sprinkler system, a person needs to know a few basic
details about the performance of the system in order to efficiently apply
water. First, one should know the irrigation rate of the system, in inches
(centimeters) of water applied per hour. This can be easily determined by
calibrating the sprinkler system (1). Next, one needs to know when to water,
how much water to apply, and the method of applying water. Specific irri-
gation instructions can be found in Watering Your Florida Lawn (2).
Efficient water use and conservation of irrigation water are the responsi-
bility of the system operator and require knowledge of turfgrass water re-
quirements and sprinkler system capabilities. Proper turfgrass management
practices are also essential in making the most effective use of rainfall and
applied irrigation. Information on Florida turfgrass culture is available at all
county extension offices.

Utilizing Irrigation Requirement Tables

Irrigation requirements (Tables 2 through 10) found in this publication
were computed following the methods reported in Irrigation Water Require-
ments by the United States Department of Agriculture (USDA) Soil Conser-
vation Service (28). These tables are meant to be used as a guide for planning
turfgrass irrigation in various locations throughout Florida. Information
contained herein reflects the need for irrigation based on historical climato-
logical data and probability of these occurrences.
Mean monthly temperature and rainfall data presented are for the official
weather station in each location and are from reporting periods averaging 52
years in duration (17). The mean monthly temperature data was used to cal-
culate potential evapotranspiration by McCloud's method as previously dis-
Net irrigation requirement (NIR) is the amount of water irrigation has to
supply to meet turfgrass consumptive demands. Net irrigation requirements
were calculated making several basic assumptions. First, there was no
carryover from month to month because of low moisture holding capacity of
sand soils, and the relatively shallow turfgrass root systems. Second, rainfall
was adjusted for frequency distribution of effective rainfall. This provided an
estimation of the portion of the total monthly rainfall used by turf for eight
out of ten years. Net irrigation requirements were then determined by the
difference between potential evapotranspiration and effective rainfall.
Losses of irrigation water do occur by evaporation, percolation, and run-
off and therefore more water needs to be applied to achieve NIR levels. Gross
irrigation requirements are the amounts of water that must be applied to meet
NIR levels. Gross irrigation requirements are calculated by dividing net ir-
rigation requirements by an application efficiency factor. Water losses in ir-
rigated turf can be controlled so that losses are primarily from evaporation.
Application efficiencies range from 60 to 95 percent, and depend upon wind
speed, relative humidity, and temperature (18). Efficiencies can be maxi-
mized by irrigating when evaporation rates are the lowest, namely in early
morning when there is no wind, relative humidity is high, and temperatures
are low.
The environment of Florida provides a challenge to planning an efficient
turfgrass irrigation program. Use of these tables will help provide general
turf water requirements throughout the state of Florida. Careful planning and
proper irrigation practices will conserve this valuable resource and provide
good quality turfgrass.

Table 2. Fort Myers area turfgrass irrigation requirements based on long-term
climatic records.
Mean Mean Potential Net
Month Monthly Monthly Evapo- Irrigation
Temperature Rainfall transpiration Requirement
(F) (inches) (inches) (inches)
JAN 63.5 1.64 2.61 1.65
FEB 64.7 2.03 2.56 1.38
MAR 68.5 3.06 3.66 1.86
APR 73.3 2.03 4.92 3.57
MAY 77.7 3.99 6.82 4.12
JUN 81.1 8.89 8.31 2.51
JUL 82.5 8.90 9.46 3.26
AUG 82.8 7.72 9.61 4.06
SEP 81.6 8.71 8.61 2.91
OCT 76.4 4.37 6.26 1.54
NOV 69.4 1.31 3.78 2.96
DEC 64.8 1.30 2.85 2.07
TOTAL 53.95 69.45 31.89
AVG. 73.9

Table 3. Gainesville area turfgrass irrigation requirements based on long-term
climatic records.
Mean Mean Potential Net
Month Monthly Monthly Evapo- Irrigation
Temperature Rainfall transpiration Requirement
(F) (inches) (inches) (inches)
JAN 57.0 2.84 1.68 0.18
FEB 58.6 3.70 1.69 none
MAR 63.6 4.26 2.63 0.38
APR 70.0 3.02 3.92 2.12
MAY 75.8 3.54 6.00 3.70
JUN 80.0 6.81 7.71 3.21
JUL 81.1 8.03 8.59 3.09
AUG 81.2 8.25 8.65 2.85
SEP 79.1 5.67 7.26 3.51
OCT 71.8 3.67 4.58 2.38
NOV 63.3 1.92 2.49 1.44
DEC 57.8 2.88 1.78 0.58
TOTAL 54.59 56.98 23.44
AVG. 69.9

Table 4. Jacksonville area turfgrass irrigation requirements based on long-term
climatic records.
Mean Mean Potential Net
Month Monthly Monthly Evapo- Irrigation
Temperature Rainfall transpiration Requirement
(F) (inches) (inches) (inches)
JAN 54.6 2.78 1.43 none
FEB 56.3 3.58 1.45 none
MAR 61.2 3.56 2.24 0.34
APR 68.1 3.07 3.45 1.70
MAY 74.3 3.22 5.43 3.34
JUN 79.2 6.27 7.32 3.22
JUL 81.0 7.35 8.53 3.53
AUG 81.0 7.89 8.53 3.23
SEP 78.2 7.83 6.84 1.94
OCT 70.5 4.54 4.19 1.59
NOV 61.2 1.79 2.16 1.16
DEC 55.4 2.59 1.51 none
TOTAL 54.47 53.08 20.05
AVG. 68.4

Table 5. Miami area turfgrass irrigation requirements based on long-term
climatic records.
Mean Mean Potential Net
Month Monthly Monthly Evapo- Irrigation
Temperature Rainfall transpiration Requirement
(F) (inches) (inches) (inches)
JAN 67.2 2.15 3.35 2.09
FEB 67.8 1.95 3.16 1.99
MAR 71.3 2.07 4.42 3.12
APR 75.0 3.60 5.50 3.24
MAY 78.0 6.12 6.97 3.05
JUN 81.0 9.00 8.26 2.69
JUL 82.3 6.91 9.32 4.32
AUG 82.9 6.72 9.71 4.75
SEP 81.7 8.74 8.66 2.74
OCT 77.8 8.18 6.87 1.13
NOV 72.2 2.72 4.55 2.85
DEC 68.3 1.64 3.61 2.61
TOTAL 59.80 74.38 34.58
AVG. 75.5

Table 6. Orlando area turfgrass irrigation requirements based on long-term
climatic records.
Mean Mean Potential Net
Month Monthly Monthly Evapo- Irrigation
Temperature Rainfall transpiration Requirement
(F) (inches) (inches) (inches)
JAN 60.4 2.28 2.12 0.85
FEB 61.8 2.95 2.10 0.55
MAR 66.3 3.46 3.16 1.26
APR 72.2 2.72 4.56 2.88
MAY 77.5 2.94 6.73 4.73
JUN 81.2 7.11 8.37 3.57
JUL 82.4 8.29 9.39 3.59
AUG 82.7 6.73 9.58 4.68
SEP 81.1 7.20 8.31 3.41
OCT 75.0 4.07 5.67 3.17
NOV 67.1 1.56 3.21 2.28
DEC 61.8 1.90 2.33 1.19
TOTAL 51.21 65.53 32.16
AVG. 72.5

Table 7. Pensacola area turfgrass irrigation requirements based on long-term
climatic records.
Mean Mean Potential Net
Month Monthly Monthly Evapo- Irrigation
Temperature Rainfall transpiration Requirement
(F) (inches) (inches) (inches)







Table 8. Tallahassee area turfgrass irrigation requirements based on long-term
climatic records.
Mean Mean Potential Net
Month Monthly Monthly Evapo- Irrigation
Temperature Rainfall transpiration Requirement
(F) (inches) (inches) (inches)
JAN 52.6 3.74 1.25 none
FEB 54.8 4.77 1.31 none
MAR 60.3 5.93 2.10 none
APR 67.9 4.07 3.39 1.09
MAY 74.8 4.04 5.58 3.28
JUN 80.0 6.62 7.71 3.21
JUL 81.1 8.92 8.59 2.59
AUG 81.1 6.89 8.59 3.79
SEP 78.1 6.64 6.78 2.58
OCT 69.3 2.93 3.88 2.13
NOV 58.9 2.81 1.85 0.35
DEC 53.2 4.22 1.30 none
TOTAL 61.58 52.33 19.02
AVG. 67.7

Table 9. Tampa area turfgrass irrigation requirements based on long-term climatic
Mean Mean Potential Net
Month Monthly Monthly Evapo- Irrigation
Temperature Rainfall transpiration Requirement
(F) (inches) (inches) (inches)
JAN 60.4 2.33 2.12 0.82
FEB 61.8 2.86 2.10 0.57
MAR 66.0 3.89 3.09 0.99
APR 72.0 2.10 4.50 3.15
MAY 77.2 2.41 6.60 4.90
JUN 81.0 6.49 8.25 3.85
JUL 81.9 8.43 9.08 3.38
AUG 82.2 8.00 9.27 3.67
SEP 80.8 6.35 8.16 3.96
OCT 74.7 2.54 5.58 3.93
NOV 66.8 1.79 3.15 2.10
DEC 61.6 2.19 2.30 1.07
TOTAL 49.38 64.20 32.39
AVG. 72.2

Table 10. West Palm Beach area turfgrass irrigation requirements based on long-
term climatic records.
Mean Mean Potential Net
Month Monthly Monthly Evapo- Irrigation
Temperature Rainfall transpiration Requirement
(F) (inches) (inches) (inches)
JAN 65.5 2.60 2.99 1.49
FEB 66.1 2.60 2.81 1.34
MAR 69.8 3.32 4.00 1.95
APR 73.9 3.51 5.11 3.11
MAY 77.5 5.17 6.73 3.33
JUN 80.5 8.14 7.98 2.68
JUL 81.9 6.52 9.07 4.47
AUG 82.3 6.91 9.32 4.32
SEP 81.5 9.85 8.54 2.04
OCT 77.2 8.75 6.60 1.30
NOV 71.0 2.48 4.20 2.65
DEC 66.8 2.21 3.27 1.97
TOTAL 62.06 70.62 30.65
AVG. 74.5

Table 11. Conversion factors for turfgrass irrigation.

Gross Irrigation Requirement = Net Irrigation Requirement
Application Efficiency
1 Acre inch of water = 27,154 gallons
1 Acre inch of water = 1.028 hectare-centimeter of water
Liters = Gallons x 3.78
Centimeters = Inches x 2.54
Millimeters = Inches x 25.4
Celsius = ("Fahrenheit 32)/1.8

Literature Cited

1. Augustin, B. J. 1981. How to calibrate your sprinkler system. Fla. Coop. Ext.
Serv. Fact Sheet OH-61.
2. Augustin, B. J. 1981. Watering your Florida lawn. Fla. Coop. Ext. Serv. Fact
Sheet OH-9.
3. Beard, J. B. 1973. Turfgrass: science and culture. Prentice-Hall. Englewood
Cliffs, NJ.
4. Biran, I., B. Bravdo, I. Bushkin-Harav, and E. Rawitz. 1981. Water consump-
tion and growth rate of 11 turfgrasses as affected by mowing height, irrigation
frequency, and soil moisture. Agron. J. 73:85-90.
5. Blaney, H. E and W D. Criddle. 1950. Determining water requirements in ir-
rigated areas from climatological data. U.S.D.A. Soil Conservation Service
Tech. Pub. 96.
6. Campbell, G. S. 1977. An introduction to environmental biophysics. Springer-
Verlag. New York.
7. Chang, J. H. 1968. Climate and agriculture: An ecological survey. Aldine Pub-
lishing. Chicago.
8. Ekern, P C. 1966. Evapotranspiration by bermudagrass sod, Cynodon dactylon
L. Pers., in Hawaii. Agron. J. 58:587-590.
9. Getz, R. 1979. Florida daily temperature normals. Fla. Coop. Ext. Serv. Cir-
cular 464.
10. Jensen, M. E. (ed.) Consumptive use of water and irrigation requirements.
Amer. Soc. Civil. Engineers. New York.
11. Kneebone, W R. and I. L. Pepper. 1982. Consumptive water use by sub-
irrigated turfgrasses under desert conditions. Agron. J. 74:419-423.
12. Lange, O. L., L. Kappen, and E. D. Schulze. 1976. Water and plant life: Prob-
lems and modern approaches. Springer-Verlag. Berlin.
13. McCloud, D. E. 1955. Water requirements of field crops in Florida as influ-
enced by climate. Proc. Soil Sci. Soc. Fla. 15:165-172.
14. McCloud, D. E. 1970. Water requirements for turf. Proc. Fla. Turfgrass Mgt.
Conf. 18:88-90.
15. Meider, H. and D. W Sheriff. 1976. Plants and water. Blackie and Sons. Glas-
cow, Scotland.
16. Monteith, J. L. (ed.) 1976. Vegetation and the atmosphere. Volume 2: Case stud-
ies. Academic Press. London.
17. National Oceanic and Atmospheric Administration. 1980. Climatological data
annual summary, Florida. 84 (13) National Climatic Center. Asheville, NC.
18. Pair, C. H., W W. Hinz, C. Reid, and K. R. Frost. 1975. Sprinkler irrigation.
The Irrigation Association. Silver Spring, MD.

19. Penman, H. L. 1948. Natural evaporation from open water, bare soil, and grass.
Proc. Royal Soc. Series A 193:120-145.
20. Rosenberg, N. J. 1969. Seasonal patterns in evapotranspiration by alfalfa in the
central Great Plains. Agron. J. 61:879-886.
21. Rosenberg, N. J. 1974. Microclimate: The biological environment. John Wiley
& Sons. New York.
22. Sarsfield, A. C. 1966. The A B Cs of lawn sprinkler systems. Irrigation Tech-
nical Services. Lafayette, CA.
23. Speir, W H. 1962. Installation and operation of non-weighing lysimeters. Soil
Crop Soc. Fla. 22:167-176.
24. Stewart, E. H., J. E. Browning, and E. O. Burt. 1969. Evapotranspiration as
affected by plant density and water table depth. Trans. A.S.A.E. 12:646-647.
25. Stewart, E. H. and W C. Mills. 1967. Effect of depth of water table and
plant density on evapotranspiration rate in southern Florida. Trans. A.S.A.E.
26. Thornthwaite, C. W 1948. An approach toward a rational classification of cli-
mate. Geo. Rev. 38:55-94.
27. Tovey, R., J. S. Spencer, and D. C. Muckel. 1969. Turfgrass evapotranspiration.
Agron. J. 61:863-867.
28. U.S.D.A. Soil Conservation Service. 1970. Irrigation water requirements. En-
gineering Div. Tech. Rel. 21 Rev. 2.
29. Van Bavel, C. H. M. 1961. Lysimetric measurement of evapotranspiration in
eastern United States. Soil Sci. Soc.. Proc. 25:138-141.
30. Watkins, J. A. 1978. Turf irrigation manual. Telsco Industries. Dallas, TX.
31. Weaver, H. A. and J. C. Stevens. 1963. Relation of evaporation to potential
evapotranspiration. Trans. A.S.A.E. 6:55-56.

This public document was promulgated at a cost of $872.78, or 32
cents per copy, to provide information on water requirements of
Florida turfgrasses. 12-2.7M-83

Tefertller, director, In cooperation with the Unltel States Department
of Agriculture, publishes this Information to further the purpose of the
May 8 and June 30, 1914 Acts of Congress; and is authorized to pro-
vide research, educational Information and other services only to Indl-
viduals and Institutions that function without regard to race, color, sex or national ori-
gin. Single copies of Extension publications (excluding 4-H and Youth publications) are
available free to Florida residents from County Extension Offices. Information on bulk
rates or copies fdr out-of-state purchasers Is available from C. M. HInton, Publications
Distribution Center, IFAS Building 664, University of Florida, Galnesvllle, Florida
32611. Before publicizing this publication, editors should contact this address to deter-
mine availability.

University of Florida Home Page
© 2004 - 2010 University of Florida George A. Smathers Libraries.
All rights reserved.

Acceptable Use, Copyright, and Disclaimer Statement
Last updated October 10, 2010 - - mvs