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
Agricultural Research Center, Ona
Research Report RC-1979-5 (BCSC) May 1979
/00 INVESTIGATIONS ON NATIVE RANGE
R. S. Kalmbacher
Native pastures represent a valuable forage re re f" mated
2,700 Florida ranchers. Their 8.6 million a ,r1ro. yd s land
waiting to be "improved", but as a management aT Mnaive in the tot l
pasture system. Few ranchers rely entirely cn imp rId ne iial or annual
pastures. In any properly functioning system cattyW and m nage
species of different capabilities to provide a year-round supply of orage
to meet the needs of cattle. I.F.A.S.-Uni. of Florida
Unlike bahiagrass most native grasses are fragile. There are no
"Pensacola" varieties of creeping bluestem or maidencane that will withstand
continuous overgrazing, and once they are gone from the pasture, they cannot
be easily r-_establishd. The result is a long-term reduction in forage
and livestock yield.
A team of scientists in the Institute of Food and Agricultural Sciences
(IFAS) are studying native forage grasses to learn how to utilize them to
their fullest potential without destroying the resource. Range research in
Florida is conducted to provide recommendations for better management and
use of native forages. Researchers from IFAS and the U. S. Forest Service
are working on problems which vary from management of tall grasses in south
Florida to forage production on pine plantations in north Florida. The
following is a summary of most of the on-going native forage research programs.
Ona Agricultural Research Center
One of the main reasons for the establishment of the Ona ARC was to work
on range problems and a number of studies have been conducted at the center.
During the past three years several new studies have been initiated. All
these fall into one of three categories: plant response to clipping and/or
grazing; studies of the nutritional value; and the development of procedures
for improving range.
If there is one native forage that is receiving the most attention at
Ona, it's creeping bluestem. This is a relatively high yielding flatwoods
grass that spreads rapidly by rhizomes or underground stems. We feel it is
definitely one of the species that should be a major part of the pasture
sward. Past research has indicated that chopping and resting flatwoods
resulted in a change in botanical composition with creeping bluestem and
associated desirable species increasing. Tandem chopping can be valuable for
reducing palmetto cover so that grasses can thrive, but we need to know how
to manage the grasses so that once the palmettos have been reduced the grasses
continue to increase thus improving range conditions and grazing capacity.
Assistant Agronomist, Agricultural Research Center, Ona, Florida 33865.
Creeping bluestem has been subjected to moderate (50% of the forage),
heavy (leaving a 6-8" stubble) or no grazing. Forage has been grazed every
60 days throughout the year; in June, Augurt, and October; in October,
December, and February; or February, April, and June.
It appears that winter grazing is least detrimental to the rate of
bluestem spread, whereas grazing every 60 days or grazing heavily in
February, April and June reduced tiller number and rate of spread.
Yield and quality data have been obtained. Under Ona conditions
creeping bluestem yields about 2,000 lb/A of dry matter when cut at a 4"
stubble. Forage cut at a 4 inch stubble yielded 1000 Ib/A from June to
October; 400 Ib/A from October to February and about 750 Ib/A from March
to June. Crude protein of summer (June to October) produced forage averaged
5.3% on a dry matter basis as compared to 4.4%.in forage stockpiled through
the summer and sampled in October. Percent in vitro organic matter diges-
tility (IVOMD) of forage produced in the summer averaged 40.4% vs 31.5%
for the forage stockpiled and sampled in October.
Nutritional qualities of creeping bluestem are low, but the fluctuation
or drop in quality with increases in maturity are not great. Observations
indicate that quality can be improved by a combination of summer and winter
It was suspected that grazing creeping bluestem after a winter burn
would decrease stands if the grass was grazed heavily in the spring and
early summer after the burn. Both annual yield and the number of tillers
of burned forage was not reduced by cutting to a 4" stubble on 2 month
intervals beginning at 2, 4, 6 or 8 months after a February burn. Tiller
number/unit area all increased as a result of burning, and yield of all
cutting treatments was approximately 2,000 Ib/A of dry matter. A relationship
between burning and clipping exists, however, we have not thoroughly defined
Success in controlling saw palmettos by chopping or herbicides has been
variable in south Florida. Some variation and perhaps lack of control may
be due to the time of treatment. All plants have times or can be forced
into a condition when they are weakest and most vulnerable to control.
At Ona we have been studying ways to make palmettos more susceptible
to death as a result of herbicides or chopping. Specifically we have burned
(or not burned) palmettos and applied a herbicide (2, 4, 5-T) in June or
October after the burn. Best control (72% mortality) was obtained by applying
2, 4, 5-T in June to February-burned palmettos. Better control has been
associated with lowest levels of total available carbohydrates in the plant.
We are not advocating use of herbicides for palmetto control. We merely used
them as a tool to measure the effect of stress on a metabolically weakened
plant. Continuing studies include the use of chopping in June or October to
see if our results can be duplicated.
North Florida Research
North Florida Research is under the direction of Dr. Dennis Hunter (IFAS)
and Mr. Bill Moore (U.S. Forest Service). Research can be divided into five
major experiments: 1) Range and wildlife studies on the Austin Cary Forest;
2) Marsh grazing in the Kissimmce River Valley; 3) Short duration grazing at
the Beef Research Unit; 4) Forage production in slash-pine plantations;
5) Forage quality.
A five year study on the Austin Cary Memorial Forest in Alachua County,
Florida is under-way to evaluate the effects of short duration cattle
grazing systems on livestock forage production, wildlife habitat and growth
and yield of slash pines. Specific treatments that have been imposed by
these investigators are: clear-cut and chop; clear-cut, chop and plant slash
pine on 8' x 12' spacing; clear-cut, chop and plant slash pine in double
rows 4' x (8', 40'); and finally, no site treatment. Grazing treatments are:
no grazing; graze and rest 3 months; graze and rest 4 months; and graze, resting
6 months. All grazing regimes are to: remove 50% of the grazable forage and
vary the length of rest.
The past 2 years have been spent in preparation with grazing to begin
in April, 1979. The results should prove valuable for cattlemen managing land
for livestock and timber.
Most of the research projects are inter-related such that results of one
study are employed for re-testing within another study. An example is the
use of data from a short duration grazing systems study conducted at the
Beef Research Unit (BRU), in Gainesville, which was applied to the Austin
Cary experiment. The BRU study revealed that a 2 month rest period was an
insufficient forage recovery period. A 4 month recovery period was best in
terms of forage production and quality. Resting 6 or 12 months resulted in
forage quality losses.
Another study, where IFAS range scientists have made important findings,
was conducted by Mr. Mark Ball, a graduate student working under the direction
Sof Dr. Hunter.: Mr. Ball investigated forage production on a bedded slash
pine plantation in North Florida and found that there were three distinct
ecological places or nichess' created by the forest bedding process. These
niches were 1) the top of the bed where trees were planted; 2) the furrow
from which soil was takenI to make the bed; 3) the relatively undistrubed
soil between beds. Forage production was greatest between beds, followed by
production on the bed, and production was least in the furrow. The important
practical application of his results is to alter the configuration of pine
plantations by making wider spacing between tree rows and increasing row
density of trees to maintain equal tree populations/acre. This application
will be made on the Austin Cary experiment.
V/ Range research faculty in Gainesville have been working in the Kissimmee
River valley to study forage-livestock relationships. Their work is sanctioned
by the Coordinating Council on the Restoration of the Kissimmee River Valley,
a council created in 1976 by the Florida Legislature. Extensive drainage of
marsh lands in the past has allowed for rapid runoff. Not only has this
detrimentally affected water quality downstream, but has resulted in longer
grazing periods. Dr. Hunter and his team have shown that the access afforded
by drainage has deteriorated many marsh:or slough sites. The desirable
maidencane has been "grazed out" of these sites and has been replaced by
carpetgrass. If marshes have not been drained the maidencate has been
utilized by cattle but protected from overgrazing by water. Cattle will not
graze below the water level, thereby leaving maidencane parts to sustain the
plants. Their continued studies will center on management of forage through
water table manipulation.
Another on-going study being carried out by the North Florida group
is the definition of crude protein, in vitro organic matter digestibility
(IVOMD), and mineral content of 30 to 40 native forages. This work will
aid in the estimates of cattle diets at different seasons. Many analyses
are completed, but the data are not ready for publication.
If productive range is to be developed and maintained an active
support through research programs is essential, and to this IFAS is committed
through systematic, logical experiments.