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IN'


RESEARCH


Institute of


Food and Agricultural


Sciences


University of Florida


Publ. FL 79-1
Agricultural Research
Center
3205 S.W. 70th Ave.
Ft. Lauderdale 33314


_


TURFGRASS






WELCOME

I appreciate your visit to the Research Center, and
the chance to introduce you to our turfgrass research.
What we will show you is a part of a broad program whose
ultimate aim is to improve the aesthetics and quality
of life in urban areas. Much of our effort is devoted to
developing technology to help solve some of the problems
of producing, protecting, and managing turfgrasses and
ornamental plants. We are also striving to improve the
conservation, management, and quality of water resources
for urban and other areas.
Turf is a vital component of the urban environment
and large resources are invested in it. The growing of
turfgrasses represents a financial commitment in Florida
of over half a billion dollars per year. That's how
valuable the aesthetic and recreational benefits of turf
are to the people who live here. Presently unmeasured are
the added benefits of turf for preventing wind and water
erosion and for providing a more healthful environment
for all citizens.
Serious questions have been raised about how
environmental quality is lowered through fertilization,
pest control, and other operations associated with grow-
ing turfgrasses. Regulatory measures exist and are
planned in attempts to correct actual or potential water
pollution resulting from agriculture-type practices in
urban areas. South Florida is one of the most enjoyable
places to live in the United States and we must protect
the fragile hydrogeologic system of this part of the
state for future generations. To meet this challenge and
to understand more fully the effect of fertilizers and
pesticides on an urban environment we have initiated new
program directions for 1979. New thrusts will supplement
ongoing research in turfgrasses, ornamental plants,
lethal yellowing, aquatic weeds, and citrus blackfly.
I am proud of this team and the mandate we have to
serve the citizens of Florida through research and
extension. We solicit your suggestions on how to make
these programs more effective and more responsive to
your needs. Have a good day!
W. B. Ennis, Jr.
Center Director








IFAS TURFGRASS FIELD DAY


at

AGRICULTURAL RESEARCH CENTER FORT LAUDERDALE

and

BROWARD COUNTY COOPERATIVE EXTENSION SERVICE

9 JANUARY 1979

9:00 10:30 Research Review

Research challenges of urban areas; Subsurface
irrigation and manganese studies; Turf management
for weed control and the problem of grass under
stress; Integrated turf management and costs analysis;
Turfgrass resistance to pests and stress; Turf
diseases; Statewide turfgrass research.

10:30 12:00 Turfgrass Research Challenges & Needs

(As perceived by Extension personnel, by county:)
Broward L. E. Watson Monroe R. H. Zerba
Collier C. A. Lowery Palm Beach G. W. Swan
Dade . L. J. Daigle Pinellas G. M. Whitton
Lee .. R. G. Curtis Sarasota L. L. Rozar
Martin R. B. Whitty Statewide H. G. Meyers

As perceived by turfgrass managers and others
interested in better turf: AUDIENCE RESPONSE.

12:00 1:00 Lunch

1:00 3:00 Guided Tour of Active Research Projects

Irrigation and fertilization; Improvement of turf-
grasses; Investigations for disease and nematode
control; Sedge control; Insect control; Integrated
pest management for turfgrasses; Evaluation of new
ornamentals; and other exhibits and demonstrations.






WELCOME

I appreciate your visit to the Research Center, and
the chance to introduce you to our turfgrass research.
What we will show you is a part of a broad program whose
ultimate aim is to improve the aesthetics and quality
of life in urban areas. Much of our effort is devoted to
developing technology to help solve some of the problems
of producing, protecting, and managing turfgrasses and
ornamental plants. We are also striving to improve the
conservation, management, and quality of water resources
for urban and other areas.
Turf is a vital component of the urban environment
and large resources are invested in it. The growing of
turfgrasses represents a financial commitment in Florida
of over half a billion dollars per year. That's how
valuable the aesthetic and recreational benefits of turf
are to the people who live here. Presently unmeasured are
the added benefits of turf for preventing wind and water
erosion and for providing a more healthful environment
for all citizens.
Serious questions have been raised about how
environmental quality is lowered through fertilization,
pest control, and other operations associated with grow-
- ing turfgrasses. Regulatory measures exist and are
planned in attempts to correct actual or potential water
pollution resulting from agriculture-type practices in
urban areas. South Florida is one of the most enjoyable
places to live in the United States and we must protect
the fragile hydrogeologic system of this part of the
state for future generations. To meet this challenge and
to understand more fully the effect of fertilizers and
pesticides on an urban environment we have initiated new
program directions for 1979. New thrusts will supplement
ongoing research in turfgrasses, ornamental plants,
lethal yellowing, aquatic weeds, and citrus blackfly.
I am proud of this team and the mandate we have to
serve the citizens of Florida through research and
extension. We solicit your suggestions on how to make
these programs more effective and more responsive to
your needs. Have a good day!
W. B. Ennis, Jr.
Center Director








IFAS TURFGRASS FIELD DAY


at

AGRICULTURAL RESEARCH CENTER FORT LAUDERDALE

and

BROWARD COUNTY COOPERATIVE EXTENSION SERVICE


9 JANUARY 1979

9:00 10:30 Research Review


Research challenges of urban areas; Subsurface
irrigation and manganese studies; Turf management
for weed control and the problem of grass under
stress; Integrated turf management and costs analysis;
Turfgrass resistance to pests and stress; Turf
diseases; Statewide turfgrass research.

10:30 12:00 Turfgrass Research Challenges & Needs


(As perceived
Broward .
Collier .
Dade .
Lee .
Martin .


Extension
E. Watson
A. Lowery
J. Daigle
G. Curtis
B. Whitty


personnel, by
Monroe .
Palm Beach .
Pinellas .
Sarasota .
Statewide


county:)
R. H. Zerba
G. W. Swan
G. M. Whitton
L. L. Rozar
H. G. Meyers


As perceived by turfgrass managers and others
interested in better turf: AUDIENCE RESPONSE.

12:00 1:00 Lunch

1:00 3:00 Guided Tour of Active Research Projects

Irrigation and fertilization; Improvement of turf-
grasses; Investigations for disease and nematode
control; Sedge control; Insect control; Integrated
pest management for turfgrasses; Evaluation of new
ornamentals; and other exhibits and demonstrations.








RESEARCH SUMMARIES*



INTEGRATED PEST MANAGEMENT (IPM) STUDY ON TURFGRASS
J. A. Reinert, E. 0. Burt, R. A. Atilano,
G. H. Snyder, and P. Busey

A study is being established on experimental greens at
ARC-Fort Lauderdale. This study will compare greens
receiving: 1) a programmed approach of maintenance
based on current practices; 2) pest control applications
only when pests are out of hand or as needed to correct
crises; and 3) a monitored management approach with
applications based on pest thresholds. In this study,
weeds, diseases, nematodes, mites, and insects will be
monitored and evaluated for different pest management
strategies. Fertility will be monitored and adjusted
as a separate factor, at high and low levels. It is
, the purpose of this study to develop and evaluate a
monitoring system to maintain grass in an acceptable
condition by applying treatments when it is optimal to
do so. As the study develops, other aspects of manage-
ment will be incorporated, including host-plant
resistance. Once the principals are worked out in this
study, additional studies will be conducted to apply
a comparable system of integrated pest management for
home lawns.






,,.,



Mention of any trade name herein does not constitute an
endorsement or recommendation of a particular product,
nor a criticism of products not mentioned. These are
summaries of work in progress and the conclusions may
change as additional investigations are conducted.







TURF MANAGEMENT FOR BETTER WEED CONTROL E. 0. Burt

The age-old principle of controlling weeds by growing
healthy turf is as important today as ever. Modern
scientific research on this subject supports the
observations of turfgrass managers. Dense, vigorously
growing turf that is adapted to the particular site and
properly maintained is the key to weed prevention.
There is no substitute for proper watering, mowing,
fertilizing, and thatch control. Also important in
preventing weeds from gaining a foothold is the prompt
control of insects, diseases, and nematodes. On the
other hand, thin, weak turf invariably leads to weedy
turf. In most cases weeds are the result rather than
the cause of poor turf. Therefore, the first step in
any weed control program is to correct the underlying
problem causing thin, weedy turf.

Despite good turf maintenance practices, weeds--
especially the more aggressive types--do become estab-
lished. To control these weeds, herbicides can be used
Selective weed control with herbicides requires knowledge
of chemicals, turfgrasses, and weeds. Success is also
dependent upon proper application. Climatic conditions
such as temperature, humidity and rainfall, and soil
factors such as texture, organic matter, and fertility,
affect the activity of most herbicides. These factors
also affect the susceptibility of both weeds and turf
to herbicides. a


I










RESEARCH ON DISEASES AND NEMATODES ASSOCIATED WITH
TURF R. A. Atilano

Turfgrasses will be tested for resistance to fungal
and nematode pests. Nematode and fungal populations
are being propagated for this purpose. The first
disease to be screened against is gray leafspot on
St. Augustinegrass. Eventually we will test selected
grasses against Rhizoctodni and the important nematode
pests.

Turfgrass microplots will be established in fumigated
soil for the purpose of adding different population
levels of specific nematodes to each microplot. Over
a period of 2 to 3 years we hope to collect information
on the rate of increase of nematode populations. The
information obtained will help improve the precision
of nematode control recommendations, and document
critically damaging levels. The first nematode to be
studied in depth is the sting nematode, BetonotaimuA
long-icaudwat. One of the variables to be included in
the microplot studies will be fertility.

Because the number of effective nematicides for use in
turf is quite limited, potentially useful chemicals will
be tested. Some of the chemicals are still experimental,
while others need to be evaluated more extensively to
expand their current labels to use in turfgrass.

Several effective fungicides are available for control
of the major fungal diseases of turfgrasses. But with
greater restrictions on pesticide use, methods that
improve effectiveness may help to preserve chemicals that
might otherwise be removed from the market. Therefore,
evaluations will be made of fungicide application methods
* including: 1) spray volume; 2) use of surfactants; and
3) comparison of injection methods vs. drenches to
control root diseases.






STABILIZING TURF NITROGEN NUTRITION THROUGH FERTIGATION
G. H. Snyder, E. 0. Burt, and J. M. Davidson

Maintaining soil mineral nitrogen at relatively constant
and adequate levels over a period of time is difficult,
particularly in irrigated sandy soils such as are often
desired for turfgrass. A number of golf superintendents
have found that fertigation (i.e., fertilization through
the irrigation system) provides a practical and labor
saving means of making frequent fertilizations with
inexpensive soluble materials at low rates per appli-
cation. Experimental evidence that this practice helps
stabilize nitrogen nutrition as compared to conven-
tional applications of soluble materials at practical
frequencies and rates has come from a study comparing:
a) conventional nitrogen fertilization of 'Tifgreen'
bermudagrass with ammonium nitrate at three-week
intervals and b) daily fertigation using the same
nitrogen source and overall application rate (5 g N/
m2/month = 1 lb./1000 ft2/month). Daily fertigation
has generally resulted in more stable visual ratings,
clipping weights, tissue nitrogen, nitrogen concent-
ration in the root zone, and in less N leaching.

FIELD BIONOMICS OF Haptaxcu6 CtldW ON THREE SOUTHERN
TURFGRASSES J. A. Reinert

The planthopper H. ctudu6 has been considered a possible
vector of lethal yellowing disease of coconut palms and
may become a pest of turfgrass in southern Florida (it
has killed St. Augustinegrass under greenhouse culture).
Field population trends of this insect were studied on
St. Augustinegrass, bermudagrass, and bahiagrass for
1 yr. H. cAudu5 completed development on all three
grasses. Highest adult and nymphal populations were
collected from St. Augustinegrass; however, populations
were more constant on bahiagrass. There were 5
complete generations per year in Fort Lauderdale.
H. cA.uduz had a proportion of 63% females and 37% males
in this study, and a high percentage of males from one
collection date appears to indicate a population peak.






MUTATION BREEDING OF ST. AUGUSTINEGRASS P. Busey

Stolon pieces of St. Augustinegrass were irradiated
with gamma rays in an attempt to cause mutations.
Stable somatic variations were noticed in the M,
generation along with a chimeral anthocyanin change.
An optimum dosage for most materials was 4500 rads.
This dosage caused considerable (50%) growth
retardation, at an average 40% survival of nodes.
Regression coefficients of different genotypes showed
a significant (P<0.05) genotype X dosage interaction,
for growth rates and survival percentages, indicating
that there were differences among strains in gamma
irradiation tolerance. Tolerance ratings showed
no association with ploidy level, morphology, or
overall growth rate.

SUBSURFACE IRRIGATION OF BERMUDAGRASS TURF IN POMPANO
FINE SAND G. H. Snyder and E. 0. Burt

Subsurface irrigation refers to underground placement
of conventional drip irrigation systems (as opposed
to subirrigation which refers to irrigation by main-
taining a high water table). Advantages have been
claimed for subsurface irrigation. Some of these
advantages are self evident, others need experimental
verification. It has been widely claimed that less
water is needed fcr subsurface irrigation of turfgrass.
We compared two subsurface irrigation designs (point
and line source) with overhead irrigation at equal
irrigation rates, and a line source subsurface system
at two rates of irrigation vs. overhead irrigation
at the lower rate. Subsurface irrigation lines were
spaced at 45 cm and placed 10 cm deep. During periods
of high evapotranspiration and low rainfall, overhead
irrigation resulted in better appearance, less wilted
turf and greater clipping weights than subsurface
irrigation. Tensiometer readings at 10 cm depth mid-
way between subsurface lines reached much higher values
than were observed at 10 cm in overhead plots, suggesting
limited lateral and upward soil water movement. These
observations do not support the claim that less water is
required for subsurface irrigation of turf.








SURVEY OF INSECTS AND MITES ASSOCIATED WITH SOUTHERN
TURFGRASSES J. A. Reinert and cooperators: H. L.
Cromroy, A. Hammon, J. E. C. Nickerson, F. W. Mead,
and D. L. Wray

A survey of insects and mites associated with
St. Augustinegrass, bahiagrass, and bermudagrass was
conducted in southern Florida. Major groups collected
were 894,953 mites; 170,511 collembola; 30,328 scales;
27,672 ants; and 4010 thrips. When all the specimens
have been identified, their relative importance,
interactions between grass species and arthropod
groups, and ecological roles of species complexes on
these grasses will be determined.





RESPONSE OF WHITE GRUBS ON BERMUDAGRASS TO INSECTICIDE
- J. A. Reinert

White grubs (larvae of Scarab beetles) have not been a
major problem in turfgrass in Florida in past years.
However, during the last five years, a complex of four
species (Bothynun AbtALopicus, StkategU antaeus,
Phyllophaga sp., and Cyclocephata ptarUefta) has caused
considerable damage to bermudagrass on golf courses,
St. Augustinegrass in residential lawns, and on both
grasses in industrial plantings and other turf areas.
Fifteen insecticides were evaluated at various rates
for control of the grub complex during 1975-1977.
Consistent control was obtained with carbofuran,
isazofos (CGA-12223), and fonofos. These three
insecticides do not have labels for grub control at this ,
time. Some control was also obtained with diazinon and
trichlorfon (Dylox or Proxol') which are labeled for
grub control. A maximum sample population of 82 grubs/
0.09 m2 (1 ft2) was obtained in 1976.







FIELD EVALUATION OF AFRICAN BERMUDAGRASS INTRODUCTIONS
- P. Busey

Field-level adaptation is the ability of a turf to stand
up to the complex stresses present under normal growing
conditions. Field-level adaptation is desired for new
cultivars--at present, no useable model has been
achieved for systematically weighting all their interac-
tions of pest and envionrmental stresses that impinge
on a genotype, and thereby affect its value. In July
of 1976, 69 bermudagrasses were obtained from the
Southern Regional Plant Introduction Station. Of these,
43 were chosen on the basis of visual absence of sod
webworms and leafhoppers, or distinctive morphology.
These were sprigged along with five other experimental,
and cultivars 'Tifway' and 'Tifgreen', in 2 X 5 m plots,
blocked in two reps. Plots were mowed every 7-10 days
at 2.5 cm (1 inch) and fertilized with 2 g N/m2/month
(0.4 lb/1000 ft2). No effort was made to control weeds,
insects, or other pests, with the exception of one
application of 2,4-D to control matchweed. Bermudagrass
accessions were deterred from invading adjoining plots
by the use of glyphosate (Roundup--). A heavy infestation
of sedges and builgrass developed, crowding out most of
the bermudagrass. Visual ratings of percent coverage
were made on five dates, and the data averaged and
analyzed through the use of the computer program GENOS.
Genotypic differences in coverage were present (P<0.001)
for both the coarse types and the fine types. Mean
coverage was 32.5% for the coarse-textured bermudagrasses
(range 4-62%) and 29.5% for the fine bermidagrasses
(range 3-70%). Four fine-textured types averaging 58%
coverage and seven coarse-textured types averaging 54%
were better than 'Tifgreen' (21.5%) and 'Tifway' (23.3%)
(P=0.05).

Field-level performance is an important tool in
preliminary screening of large numbers of genotypes. One
of the superior strains from this study turned out
subsequently to be superior in sod webworm resistance.
Several genotypes should be investigated in terms of
a possible allelopathic reaction to weeds.








NATURAL ENEMY COMPLEX.OF THE SOUTHERN CHINCH BUG
- J. A. Reinert

Several biotic control agents have been found which
feed on the southern chinch bug, B/i"&uA in6uttab,
in Florida. A scelionid egg parasite, EumLcAosoman
benejicai, was the only parasite. Predatory bugs
included: 2 lygaeids, Geocof" btatwfu6 and G.
uLi pnoz s; a nabid, Papgta palipes; 2 anthrocorids,
Xyitokco& ticatius and La-iochitu patZiduls; and
a reduviid, Sinea sp. Other predators include a
dermapteran, Labidut.a Apakia; several ant species,
primarily SolenopiLs g iLnata, and a spider, Lycosa
sp. A fungus, Beauctiit bazsiana, also attacks the
southern chinch bug. The biotic control agents that
appear to most regulate populations of the southern
chinch bug are: E. bene fcia, G. uUigLnosts,
X. vLcarius, and L. Aipauia. I have observed natural
infestation of southern chinchbugs held 'in check by
several of these biotic control agents.








SOUTHERN CHINCH BUG RESISTANCE IN ST. AUGUSTINEGRASS
- J. A. Reinert and A. E. Dudeck

Seventy-eight accessions of St. Augustinegrass have
been evaluated for resistance to the southern chinch
bug, BW&64Su inbtauiV 'Floratam', FA-46, -64, -73,
-80, -87, -118, -121, -131, -145, -217, and -243 have
shown a high level of antibiosis (ability to kill the
confined feeding bugs) to the southern chinch bug
when compared to common St. Augustinegrass. 'Floratam'
was released in 1973 for its resistance to the southern
chinch bug and also St. Augustine Decline Virus (SAD).
In laboratory and field tests the southern chinch bug
has not been observed to develop through its life stages
on 'Floratam', but limited numbers of adults can survive
on it and have lived for 30 days. 'Floratam' is being
planted extensively in Florida to overcome the organo-
phosphate resistant chinch bug population, and is used
widely in Texas for the serious SAD infestation.


SOUTHERN CHINCH BUG: RESISTANCE TO ORGANOPHOSPHATE
INSECTICIDES J. A. Reinert

The southern chinch bug, B&.6Ls u i~ant1aX6, is the
most serious pest of St. Augustinegrass and its feeding
causes the plants to die. Beginning late in the summer
of 1975, lawn spray operators began to observe reduced
effectiveness with various organophosphate insecticides.
By 1976 several spray companies and garden centers in
the coastal area of southern Florida (Broward and Palm
Beach Counties) report d no control of chinch bugs with
chloropyrifos (Dursban) and diazinon. Experiments
conducted on home lawns showed diazinon, chloropyrifos,
primiphos-ethyl (Primicid, ) propyl-thiopyrophosphate
(Asporl:n, trichlorfon (Dyloxk), and chlordane gave poor
control of the southern chinch bug. Laboratory tests
supported the field observations. Field tests also
showed these chinch bugs were highly susceptible to
propoxur (BaygonR)--which is labeled for use--and two
synthetic pyrethroids--which do not have labeling at
this time. 44








BERMUDAGRASS RESISTANCE TO THE TROPICAL SOD WEBWORM
- J. A. Reinert and P. Busey

Seven accessions of bermudagrass were screened for -
ovipositional preference by tropical sod webworm
(HeApeatogamcma phaeopteVat-W). These included
cultivated varieties, as well as experimental strains
selected from the breeding program. One accession,
PI-289922 received low depositions of eggs when comp-
ared to currently grown cultivars such as 'Ormond,'
'Tifgreen,' and 'Tifway.' The resulting low density
worm populations on PI-289922 did not noticeably
injure this accession, but the higher densities on
the other strains resulted in damage to the grass.





RESISTANCE IN BERMUDAGRASS TO THE BERMUDAGRASS MITE
- J. A. Reinert, A. E. Dudeck, and G. H. Snyder

Eight accessions o2 bermudagrass were evaluated for
resistance to the bermudagrass mite, Efuiophyea.
cynodonien-i6, under hydroponic culture in the green-
house. Mite populations failed to become established
on FB-119 during an 8 month experiment. 'Tifway' and
FB-141 became infested in only 44% and 50% of the
plants, respectively. No difference in infestation
level resulted from varied N levels available to the
plants. FB-119 has been observed and sampled in
field plots adjacent to bermudagrass mite infestations
for a period of ca. 6 yr, with no occurrence or
indication of this eriophyid mite in FB-119. The
hydroponic culture technique was very satisfactory
for holding and screening the accessions for resist-
ance.


__








BREEDING A BETTER BAHIAGRASS FOR BETTER HIGHWAYS
- P. Busey and E. 0. Burt

Plant breeding is a product development process that
requires a number of years. In anticipating the need
for a strong foundation in the breeding program,
bahiagrasses were obtained in October 1976 from the
Southern Regional Plant Introduction Station. These
were supplemented by over 70 accessions collected at
widely scattered sites from east central Texas to
southern North Carolina, from 1977 to 1978. A diverse
foundation for the breeding of better highway grasses
was thus established.

Field plantings were begun in 1977, and are being
extended to highway sites. Plant accessions were
evaluated for rate of coverage, seedhead production,
inflorescence height, and foliage height. Data from
several types of evaluations has been integrated and
analyzed. At the same time, approximately 725 embryo
sacs have been sectioned, and sexual mode of reproduction
established for 10 accessions. These will serve as the
principal female parents for the hybridization program.

Hybridization of selected parents has been initiated,
and will be continued with several options for the final
objective, including: 1) an all-F1 hybrid seed crop,
with superior combining abilities for coverage rate and
low seedhead count; 2) a totally nonflowering certified
stock, made up of seeds produced in a region of longer
daylength than in the region of economic use; and
3) modified population breeding techniques.

Simultaneous with this variety development program, a
number of management-related projects were conducted,
in order to integrate more effectively the proposed
new cultivar(s) with grass/management systems.







SEDGES--OUR MOST SERIOUS WEED PROBLEM E. 0. Burt

Purple nutsedge is considered to be the world's worst
weed. Sedges are the most difficult weeds to control
in our warm-season turfgrasses. Most preemergence
herbicides are ineffective. Post-emergence herbicides
such as 2 4-D give only fair to poor control. Bentazon
(Basagrarfl usually requires more than one application
to give acceptable sedge control. Following the intro-
duction of asulam (Asulo A for control of grassy weeds
in St. Augustinegrass, sedges have become much more of
a problem in turf. Recently DuPont made available to
researchers an herbicide that is highly specific to
sedges, killing them at rates of only 0.03 to 0.06
g/mL ( to lb/A). No apparent injury occurs in any
of our warm-season turfgrasses at several times that
dosage rate. Other desirable properties of the
experimental herbicide are: (1) low degree of toxicity
to mammals; (2) very little or no residual activity in
the soil; (3) must be absorbed through foliage of
sedges; and (4) has a narrow range of weed-killing
activity, i.e., effectiveness is limited almost
exclusively to sedges, with very slight activity to
spurges. Marketing by DuPont is contemplated for 1981.


A~'tc oC'iehtdd






BERMUDAGRASS RESISTANCE TO THE SOUTHERN MOLE CRICKET
J. A. Reinert and P. Busey

Ten accessions of bermudagrass were grown with and
without southern mole cricket (Scopte4micuA ace"us)
populations in screened tank cages. Several of the
accessions showed little reduction in both root and
shoot growth after several months exposure to constant
southern mole cricket populations, while other acces-
sions were severely limited due to mole cricket
burrowing and feeding activity. Accession FB-119
exhibited a stimulation in both shoot and root growth
in tanks where crickets were present. 'Tifway' and
'Tifgreen' were both severely damaged by the southern
mole crickets.

CORRECTING pH-INDUCED MANGANESE DEFICIENCY OF 'TIFGREEN'
BERMUDAGRASS TURF G. H. Snyder, G. J. Gascho and
E. 0. Burt

Turf irrigation in south Florida using high pH water can
rapidly increase the pH of poorly buffered sandy soils
common to this region. A manganese (Mn) deficiency
often may result, particularly when soil pH is raised
above 7.2. In our study, soil pH was markedly reduced
when ammonium sulfate was used as the nitrogen (N)
source (10 g N/m2/month = 2 lb/m2/month), whereas soil
pH remained above 7.2 when calcium nitrate was used at
the same N rate. We found reducing soil pH by using
ammonium sulfate as the N source to be more effective
for correcting the deficiency than manganese sulfate,
chelated or fritted manganese applications (2 g Mn/
m2) to calcium nitrate fertilized plots. By using a
series of soil fungicides and a single application
of manganese sulfate, however, we were able to achieve
substantial lasting correction of the deficiency in
calcium nitrate fertilized plots. Soil pH was a more
reliable indicator of Mn deficiency than soil Mn
obtained by several soil text extractants.


(See illustration on front cover)


I










SELECTED IFAS PUBLICATIONS ON TURFGRASSES


General works

Busey, P. 1978. Dramatic designs: A garden of grass.
Fairchild Tropical Gard. Bull. 33:10-15.
Busey, P. and E. 0. Burt. 1977. Genetics and management
of bahiagrass for better highways. pp. 109-110 in:
Agronomy Abstracts.
Neel, P. L., E. 0. Burt, P. Busey, and G. H. Snyder.
1978. Sod production in shallow beds of waste
materials. J. Amer. Soc. Hort. Sci. 103:549-553.

Insects

Reinert, J. A. 1974. Tropical sod webworm and southern
chinchbug control in Florida. Florida Entomol.
57:275-279.
Reinert, J. A. 1975. Life history of the striped
grassworm, Moc6 latipes. Annals Entomol. Soc.
Amer. 68:201-204.
Reinert, J. A. 1976. Control of sod webworms
(HeApeto gLmria spp. and Canmbu6 spp.) on bermuda-
grass. J. Econ. Entomol. 69:669-672.
Reinert, J. A. 1977. Field biology and control of
Haptaxtu6 cAudua on St. Augustinegrass and Christ-
mas palm. J. Econ. Entomol. 70:54-56.
Reinert, J. A. 1978. Natural enemy complex of the
southern chinch bug in Florida. Ann. Entomol. Soc.
Amer. 71:728-731.
Short, D. E. and J. A. Reinert. 1978. Lawn insects
and their control. IFAS Circular 427.

Diseases

Freeman, T. E. 1967. Diseases of southern turfgrasses.
IFAS Tech. Bull. 713. 31 pp.
Mullin, R. S. and T. E. Freeman. 1977. Turfgrass
diseases and their control. IFAS Circ. 221-F. 6 p.


~~- -- ~ -'~-







Weeds

Burt, E. 0. 1977. Asulam--a new herbicide for turf.
Proc. Florida Turf-Grass Manage. Conf. 25:154-156.
Burt, E. 0. 1979. Glyphosate for torpedograss and
bermudagrass control. Proc. 3rd Int. Turfgrass
Res. Conf. (In press)..
Burt, E. 0. and S. L. Carlyle. 1977. Asulam in
St. Augustinegrass. Proc. South. Weed Sci. Soc.
30:145-146.
Busey, P. 1976. Genetics and the weed problem.
World Crops 28:128-130, 100.
Neel, P. L., E. 0. Burt, and S. L. Carlyle. 1979.
Tolerance of 5 warm-season turfgrasses and 36
ornamental plants to asulam. J. Amer. Soc. Hort.
Sci. 104:129-132.

Irrigation and fertilization

Snyder, G. H. and E. 0. Burt. 1976. Nitrogen fertil-
ization of bermudagrass turf through an irrigation
system. J. Amer. Soc. Hort. Sci. 101:145-148.
Snyder, G. H., E. 0. Burt, and J. M. Davidson. 1979.
Nitrogen leaching in bermudagrass turf: Daily
fertigation vs. triweekly conventional fertil-
ization. Proc. 3rd Int. Turfgrass Conf. (In press).
Snyder, G. H., E. 0. Burt, and B. L. James. 1976.
Nitrogen fertilization of bermudagrass turf in
south Florida with urea, UF, and IBDU. Proc.
Florida State Hort. Soc. 89:326-330.
Snyder, G. H., G. J. Gascho, and E. 0. Burt. 1977.
Correcting pH induced Mn deficiency of 'Tifgreen'
bermudagrass turf. p. 113 in: Agronomy Abstracts.










(IFAS PUBLICATIONS, CONTINUED)


Improved grasses

Busey, P. 1978. GENOS: A data system for plant breeders.
p. 108 in: Agronomy Abstracts.
Busey, P. 1977. Turfgrasses for the 1980's. Proc. Florida
State Hort. Soc. 90:111-114.
Myers, B. J. and P. Busey. 1977. Analysis of genetic
variation in St. Augustinegrass (StenotaphAuum
secundatum ). p. 112 in: Agronomy Abstracts.
Reinert, J. A. and A. E. Dudeck. 1974. Southern chinch
bug resistance in St. Augustinegrass. J. Econ.
Entomol. 67:275-277.
Reinert, J. A. 1978. Antibiosis to the southern chinch
bug by St. Augustinegrass accessions. J. Econ.
Entomol. 71:21-24.
Reinert, J. A., A. E. Dudeck, and G. H. Snyder. 1979.
Resistance of bermudagrass to the bermudagrass mite.
Environ. Entomol. 8: (In press).



















Acknowledgements: Special thanks for the illustrations
to R. D. Graham (cover photo); F. W. Howard (pp. 3, 17);
L. Morgan (pp. 4, 14, 20); and A. L. Reinert (p. 11).


~~









SCIENTISTS AT FORT LAUDERDALE RESPONSIBLE FOR TURF

Administration

W. B. Ennis, Jr., Professor of Agronomy and Center
Director, Ph.D. 1948, Univ. Wisconsin; M.S. 1941,
Univ. Maine; B.S. 1939, Univ. Tennessee.

Insects

J. A. Reinert, Associate Professor of Entomology,
Ph.D. 1970, Clemson Univ.; M.S. 1968, Clemson
Univ.; B.S. 1966, Oklahoma State Univ.

Diseases

R. A. Atilano, Assistant Professor of Plant Pathology,
Ph.D. 1977, Univ. California (Riverside); M.S.
1971, Cornell Univ.; B.S. 1966, California State
Polytechnic College.

Weeds and management

E. 0. Burt, Professor of Ornamental Horticulture,
Ph.D. 1954, Ohio State Univ.; M.S. 1950, Ohio
State Univ.; B.S. 1944, Ohio State Univ.

Irrigation and fertilization

G. H. Snyder, Associate Professor of Soil Science,
AREC Belle Glade, Ph.D. 1967, Ohio State Univ.;
M.S. 1964, Ohio State Univ.; B.S. 1962, Ohio
State Univ.

Improved grasses

P. Busey, Assistant Professor of Ornamental
Horticulture, Ph.D. 1976, Univ. Arizona; M.S.
1971, Univ. Illinois; B.S. 1969, Colorado State
Univ.









Broward County Extension -
3245 SW 70th Avenue
Fort Lauderdale, FL 33314
(305)-581-8010


rAgricultural Research ui
Center
3205 SW 70th Avenue -.
( )-
( 305)-584-6990









SCIENTISTS AT FORT LAUDERDALE RESPONSIBLE FOR TURF

Administration

W. B. Ennis, Jr., Professor of Agronomy and Center
Director, Ph.D. 1948, Univ. Wisconsin; M.S. 1941,
Univ. Maine; B.S. 1939, Univ. Tennessee.

Insects

J. A. Reinert, Associate Professor of Entomology,
Ph.D. 1970, Clemson Univ.; M.S. 1968, Clemson
Univ.; B.S. 1966, Oklahoma State Univ.

Diseases

R. A. Atilano, Assistant Professor of Plant Pathology,
Ph.D. 1977, Univ. California (Riverside); M.S.
1971, Cornell Univ.; B.S. 1966, California State
Polytechnic College.

Weeds and management

E. 0. Burt, Professor of Ornamental Horticulture,
Ph.D. 1954, Ohio State Univ.; M.S. 1950, Ohio
State Univ.; B.S. 1944, Ohio State Univ.

Irrigation and fertilization

G. H. Snyder, Associate Professor of Soil Science,
AREC Belle Glade, Ph.D. 1967, Ohio State Univ.;
M.S. 1964, Ohio State Univ.; B.S. 1962, Ohio
State Univ.

Improved grasses

P. Busey, Assistant Professor of Ornamental
Horticulture, Ph.D. 1976, Univ. Arizona; M.S.
1971, Univ. Illinois; B.S. 1969, Colorado State
Univ.








Broward County Extension
3245 SW 70th Avenue
Fort Lauderdale, FL 33314
(305)-581-8010

PAgricultural Research uj
Center
3205 SW 70th Avenue o-
(305)-584-6990 C


8 84


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1













COVER: Turfgrass research plots at Fort Lauderdale.
The principle of lowering soil pH to correct Mn
deficiency is demonstrated. The lowermost rect-
angular plot received no manganese, but remains
dark green due to the lowering of soil pH.
Micronutrient availability to turf is especially
precarious on the weakly buffered sands of southern
Florida. Alkaline irrigation water is sufficient
to raise soil pH to an unacceptable level.
Ammonium sulfate is very effective in lowering
soil pH rapidly.







IFAS


This public document was promulgated at an annual
cost of $155.35 or a cost of 15.5 per copy to
inform individuals working in turfgrasses of
research progress on turf at Fort Lauderdale
Agricultural Research Center.