Stargrass field day

Material Information

Stargrass field day
Series Title:
AREC Ona research report
Agricultural Research and Education Center, Ona
Place of Publication:
Ona FL
Agricultural Research and Education Center, Institute of Food and Agricultural Sciences, University of Florida
Publication Date:
Physical Description:
9 p. : ; 28 cm.


Subjects / Keywords:
Grasses -- Varieties -- Florida ( lcsh )
Pastures -- Florida ( lcsh )
Grazing -- Florida ( lcsh )
Cane Patch ( local )
Grasses ( jstor )
Canes ( jstor )
Regrowth ( jstor )
government publication (state, provincial, terriorial, dependent) ( marcgt )
non-fiction ( marcgt )


General Note:
Cover title.
General Note:
"June 17, 1988."
Research report (Agricultural Research and Education Center, Ona) ;

Record Information

Source Institution:
University of Florida
Rights Management:
All applicable rights reserved by the source institution and holding location.
Resource Identifier:
99017852 ( OCLC )


This item has the following downloads:

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




RC 88-4
June 17, 1988

Stargrass Field Day

Institute of Food and Agricultural Sciences
University of Florida

GCJ:Url Science

JUIL 20 1S8
L : '.: : ; of Florida

Production and Management of
Puerto Rico and Cane Patch Stargrass
P. Mislevy, M. B. Adjei and A. Larbi

Puerto Rico and Cane Patch (Cynodon nlemfuensis Vanderyst var.
nlemfuensis) are two stargrasses which have been field tested at Ona for
about 15 years. Both grasses grow vigorously and spread rapidly after
planting, provided adequate moisture and fertility are available. When
planted in areas with no vegetative competition, runners 15 to 20 ft
long can develop in 30 days, rooting (pegging down) at various nodes as
they spread. Both grasses can produce dense stands in a relatively
short time after planting. When properly managed dry matter yield and
forage quality are good. These grasses have the ability to continue
producing forage into late November and December when properly
fertilized. Animal performance for both grasses has been excellent,
producing average daily gains more than double that for bahiagrass.
Persistence of both grasses has been superior to 'Ona' star, however the
persistence of Cane Patch is far superior to any stargrass tested at Ona
to date. Good quality hay has been produced from both grasses when
harvested at the proper physiological stage.

One of the most important factors when developing a forage program
to be used in a grazing system is management. The performance of a
grass on a specific soil, time of year for maximum production, seed bed
preparation, method of establishment, fertility program, grazing
management and advantages and disadvantages. Many of these factors will
be discussed for both Puerto Rico and Cane Patch stargrass.

Region of adaptation: Both grasses are well adapted to many of south
Florida's flatwood soils. The tropical nature of these stargrasses
limits its productivity and persistence to the southern two-thirds of
peninsular Florida (south of Orlando). These grasses have performed
well under saturated soil conditions, but will not tolerate long periods
of flooding.

Season of Growth: Grasses are warm season perennials, however, like
other stargrasses and bermudagrasses they will make excellent growth
under cool fall conditions. When adequate fertility is provided these
grasses could continue producing forage at a relatively high level into
late November to early December. Once these grasses are frosted, all
desirable forage must be consumed within 1 wk, since forage quality
drops rapidly. Under drought spring conditions Cane Patch tends to
produce more forage than Puerto Rico when both are well fertilized.

Growth Habit: Both grasses spread by long, above-ground runners
stolonss), similar to Ona stargrass. Under well fertilized conditions
both grasses form a relatively dense stand, with Puerto Rico expressing
a dark green color and Cane Patch a light shade of green.

Establishment: Both stargrasses are established vegetatively from
stolons (runners) or stem pieces. When placed in a moist, firm seed
bed, nodes germinate in 5 to 10 days. This is accomplished by
distributing freshly cut planting material on clean cultivated soil,
covered by disking 2 to 4 inches deep, followed by an extremely firm
packing. Fresh planting material must be disked into the seed bed
immediately after distribution to prevent drying on the soil surface.
Be sure planting material is uniformly distributed over the seed bed
with areas no larger than 3' x 3' void of planting material.

To be highly successful in the establishment of these stargrasses
the seed bed must be clean (free of common bermudagrass and all other
vegetation) and moist.

Approximately 7 to 10 days after establishment and signs of
vegetative growth appear, the newly planted area should be sprayed with
1 qt/A Weedmaster in 20 to 30 gal. of water to help control annual
sedges (water grass) and broadleaf weeds. When new tillers (shoots) are
approximately 1 to 3 inches tall the newly planted grass should be
fertilized (see fertilizing stargrass, J. E. Rechcigl). A second
application of a mixed fertilizer should be applied when plants are 6 to
8" tall. This should be sufficient to provide a dense stand of grass 24
to 30" tall within 60 to 90 days after planting.

Management and Utilization: Clipping and grazing studies have
demonstrated that both Puerto Rico and Cane Patch stargrass should be
allowed a rest period of 4 to 5 weeks between grazing or clipping.
These management variables result in excellent persistence and high dry
matter yields, with good crude protein (9 to 14%) and good digestibility
(56 to 60%). If the rest period is shorter, forage quality increases,
but persistence of the stand decreases. If the rest period is increased
to 7 weeks, persistence is improved, but crude protein (8%) and
digestibility (53%) are relatively low. Research has shown that the
digestibility of Puerto Rico is about 2 to 3 percentage units higher
than Ona and Cane Patch stargrass. The stubble height of these grasses
needs to be maintained at 6 to 10 inches for best persistence. However,
since plant height above the stubble has a major effect on forage yield
and quality, plants should be grazed when plant height ranges between 6
and 18 inches above the stubble. Grazing studies at the AREC Ona
yielded an average daily gain of 1.2 lb and 700 lb/A beef on Puerto Rico
stargrass and 0.9 lb average daily gain and 600 lb/A beef on Cane Patch
stargrass. Both grasses were stocked at 3 yearling steers/A over a 200
day summer period. The hydrocyanic acid potential (HCNp) of both
stargrasses, like Ona star, are very high. Therefore, if cattle have
not previously grazed stargrass caution should be exercised as described
in the Ona stargrass IFAS circular S-268 A.

Both stargrasses drop rapidly in forage quality after a freeze or
frost, therefore, it should be consumed by December 15. Dog fennel
control can be accomplished by applying 1 qt/A Weedmaster when
weeds are less than 6 inches or 1.5 qts/A when dog fennels are above
6 inches. This herbicide treatment also controls'many other
broadleaf weeds. Insect problems are generally limited to the
striped grass looper and fall armyworms.

Advantages and Disadvantages of Puerto Rico Stargrass



1) Digestibility about 2 to 3% higher than Ona
2) Dry matter yields generally higher than Ona
stargrass at both Ona and Immokalee.
3) Generally more persistent than Ona stargrass.
4) Two year average daily gain by steers of 1.2 lb and
700 Ib/A beef at stocking rate 3 yearling steers/A.
5) Palatable when grazed every 4 to 5 weeks.
6) Makes excellent growth in late fall, and in the
spring with adequate moisture and fertility.

1) High HCNp following heavy Nitrogen (100 lb/A)
fertilization, any time during the growing season.
2) Top growth easily killed by frost, followed by a
rapid reduction in forage quality.
3) Should not be grown north of Orlando.
4) Produces little forage during drought stressed
period of April to May.
5) Requires higher fertility program than bahia,
hemarthria and pangola.
6) Vegetatively propagated from stem cuttings.
7) Forage quality drops rapidly after 6 weeks of

Advantages and Disadvantages of Cane Patch Stargrass



1) Rapid establishment from vegetative cuttings.
2) Dry matter yields are about 15% higher than Ona
stargrass, with forage quality equal to slightly
lower than the latter.
3) Makes excellent growth in late fall and spring
(April to May) under drought stress conditions, when
adequately fertilized.
4) Extremely persistent when properly managed.
5) Steers grazing this grass had an average daily gain
of 0.9 lb and 600 lb/A beef at a stocking rate of 3
yearling steers/A over a 200 day period.
6) Palatable and high forage quality when harvested or
grazed every 4 to 5 weeks.

1) High HCNp following heavy (100 lb/A) nitrogen
fertilization, any time during the growing season.
2) Top growth easily killed by frost.
3) Should not be grown north of Orlando or where
temperatures drop below 20 to 250 F.
4) Requires high fertility.
5) Vegetatively propagated from stem cuttings.
6) Forage quality drops rapidly after 6 weeks of growth
and following a heavy frost or freeze.


W.F. Brown AREC-Ona

Due to its increased growth rate and..improved quality potential
(if managed properly) stargrass has advantages over other widely-used
tropical grasses such as bahiagrass. Examples of advantages of
stargrass include increased grazing potential during the growing
season (April to November), and for hay production. However,
stargrass quality declines rapidly after frost, and increased
management is required in order to maintain stand persistence and to
obtain adequate quality forage. A majority of the comments made in
this paper will be related to quality of conserved forage (hay,
haylage, or silage).

When adequate fertilizer is applied and moisture is available,
stargrass can grow rapidly and produce large yields in a short period
of time. However, quality of stargrass forage declines at a rapid
rate as the plant matures. Therefore a trade-off exists between yeild
and quality. The objective is to manage the forage, primarily through
maturity (weeks of regrowth), in order to obtain acceptable quality
forage for the class of cattle to which the forage will be fed. To
illustrate this, a clipping study was conducted to determine the

Table 1. Influence of maturity on the yield and quality of tropical

Weeks of regrowth, Date

2 4 6 8
8-28 9-12 9-25 10-9

YIELD (lbs DM/acre)
Ona stargrass 390 2280 4060 4710
Cane Patch stargrass 550 2080 4260 4860
Puerto Rico stargrass 740 2190 4020 5110
Pangola digitgrass 260 1530 1660 1860
Pensacola bahiagrass 500 900 1030 1150

Ona stargrass 28.1 12.7 9.7 8.3
Cane Patch stargrass 28.1 12.6 11.0 7.7
Puerto Rico stargrass 29.6 10.4 8.8 7.4
Pangola digitgrass 27.6 11.9 8.7 5.5
Pensacola bahiagrass 18.2 14.9 11.5 9.1

Ona stargrass 71.2 59.3 .50.0 47.2
Cane Patch stargrass. 70.0 56.8 49.1 38.7
Puerto Rico stargrass 70.0 60.7 53.8 48.7
Pangola digitgrass 65.9 60.9 55.8 51.2
Pensacola bahiagrass 59.6 54.5 53.8 45.6

DM = dry matter, IVOMD = in vitro organic matter digestion.

effect of maturity on the growth and quality of several tropical
grasses grown during the fall. Forage from all plots was harvested on
August 14 and discarded. Plots were then fertilized, and forage was
harvested after 2, 4, 6, and 8 weeks regrowth (Table 1). As harvest
was delayed from 2 to 8 weeks regrowth, all three stargrass varieties
grew rapidly with no large differences in yield between them. All
three stargrass varieties produced more yield than Pangola digitgrass,
which produced more yield than Pensacola bahiagrass.

The protein requirement of a lactating beef cow is approximately
10%, while the protein requirement of a growing heifer or steer is 10
to 12%. High crude protein values for all grasses at 2 weeks regrowth
is a reflection of the nitrogen fertilizer which was applied 2 weeks
earlier (Table 1). Protein value of all grasses declined rapidly as
harvest was delayed, with values below animal requirements by 6 weeks
of regrowth. No large differences existed in crude protein content
among the stargrass varieties. Protein content of Pangola digitgrass
was similar to that of the stargrass varieties until 6 weeks regrowth,
but was lower than that of the stargrass varieties at 8 weeks of
regrowth. Pensacola bahiagrass was slightly greater in protein at 4,
6 and 8 weeks regrowth than the other grasses; however, this was a
function of reduced growth rate of bahiagrass compared to the other

In vitro organic matter digestion (IVOMD) of all grasses declined
rapidly as harvest was delayed from 2 to 8 weeks regrowth (Table 1).
Puerto Rico.stargrass tended to be greater in IVOMD compared to the
other stargrass varieties, and was similar in IVOMD to Pangola
digitgrass. Pensacola bahiagrass was lowest in IVOMD. Because too
much yield must be sacrificed in order to obtain adequate quality
bahiagrass hay, other grasses such as stargrass should be considered
for hay or silage production. In order to obtain appropriate quality
forage for lactating cows or growing calves, forage should be
harvested after approximately 5 weeks regrowth.

The above clipping trial shows the influence of maturity upon
relative differences in chemical composition and in vitro digestion
among tropical grasses; however, it does not indicate animal responses
to these forages. A digestion trial was conducted to evaluate the
chemical composition, intake, and digestibility by cattle of Ona, Cane
Patch and Puerto Rico stargrass. All grasses were harvested after six
weeks regrowth in the spring and stored as hay. Forage quality
parameters were measured, and the hays were fed to cattle for the
measurement of voluntary intake and digestibility.

Crude protein content of the three grasses was similar (Table 2).
Neutral detergent fiber (NDF) and acid detergent fiber (ADF)
concentrations were high, with only small differences existing among
the three grasses. Lignin concentration (ADL) which has a large
influence on digestibility was lowest in Puerto Rico stargrass and
greatest in Cane Patch stargrass. In vitro digestion did not vary
greatly among the stargrass varieties, with the value for Puerto Rico
stargrass being slightly greater than that for Ona or Cane Patch

There were no differences in voluntary intake or organic matter
and fiber digestibilities among the three stargrass varieties
(Table 2). Although no statistical differences occurred among the
stargrass varieties, Puerto Rico stargrass had numerically greater
voluntary intake, organic matter, and fiber digestibilities compared
to Ona or Cane Patch stargrass.

Table 2. Chemical composition, intake, and digestibility of Ona, Cane
Patch and Puerto Rico stargrass.

Stargrass variety

Item Ona Cane Patch Puerto Rico

Chemical composition, %
Crude protein 8.8 8.1 9.4
NDF 75.8 77.1 79.4
ADF 39.7 .38.9 40.6
ADL 7.0 7.3 6.0
IVOMD 50.1 48.6 52.9

Digestion trial
Intake, lbs DM/day
Ad libitum 16.3 16.5 16.9
Restricted 11.0 11.0 11.0
OM digestibility, % 49.4 49.8 52.8
NDF digestibility, % 56.1 53.8 58.4
ADF digestibility, % 50.0 47.9 51.4
HC digestibility, % 60.2 60.6 62.5

NDF = neutral detergent fiber, ADF = acid detergent fiber, ADL = acid
detergent lignin, IVOMD = in vitro organic matter digestion, DM = dry
matter, OM = organic matter, HC = hemicellulose.

The importance of maturity upon forage quality and animal
performance was investigated in a digestion and cattle growth trial
using Ona stargrass (Table 3). Fall regrowth of stargrass was
harvested after 6 and 12 weeks (trial 1), and 5 and 10 weeks
(trial 2). In both trials, less mature forage was greater in crude
protein content compared to the more mature forage, with the value for
5 week regrowth being appropriate for lactating cows and growing
calves. Less mature forage was lower in fiber content content and
greater in in vitro digestion compared to more mature forage. In the
digestion trial less mature stargrass hay had greater digestibilities
of organic matter and fiber compared to more mature hay.

In growth trial 1, Brahman crossbred steers (430 lbs initial
weight) were fed ad libitum amounts of hay for 99 days in drylot pens.
In growth trial 2, Brahman crossbred heifers (450 lbs initial weight)
were placed on bahiagrass pasture from January through April and fed
ad libitum amounts of hay. In both trials the hays were supplemented

Table 3. Chemical composition and digestibility
by cattle fed, less mature compared to
stargrass hay.

Trial 1
Weeks of regrowth

6 12

Chemical composition, %
Crude protein

Digestion trial
OM digestibility
Fiber digestibility

Growth trial
Feed intake, lbs DM
Daily gain, IbS







of, and performance
more mature Ona

Trial 2
Weeks of regrowth

5 10







NDF = neutral detergent
detergent lignin, IVOMD
OM = organic matter, DM

fiber, ADF
.= in vitro
= dry matte

= acid detergent fiber, ADL = acid
organic matter digestion,

with protein. Cattle fed less mature hay ate 18 to 48% more hay and
gained over 100% more weight per day.compared to cattle fed more
mature hay.

From a conserved forage (hay, silage, haylage) standpoint very
little difference exists between the three stargrass varieties. The
more important factor influencing the feeding value of these stargrass
varieties is maturity of the forage when it is harvested. If lactating
cows or growing calves are to be fed, then stargrass forage should be
harvested after approximately 5 weeks regrowth. Factors such as stand
persistence under grazing, and performance of cattle grazing these
grasses should be considered when choosing one of these stargrass


Stargrass Fertilization

Jack Rechcigl

Proper fertilization of stargrasses is extremely important in order
to get high yields of high quality forage. Overall stargrasses have
very high fertilizer requirements, thus it is essential that a proper
fertility program be maintained.

Before a fertilizer recommendation can be made for stargrasses it
is essential that a soil test be taken and analyzed by a reputable soil
testing laboratory. A soil test will determine the nutrient status and
pH of the soil from which a fertilizer recommendation can be made.

Stargrasses generally perform well in a soil pH between 5.5 and
6.0. In this pH range nutrients are most available to the crop, whereas
if the pH is too high or too low certain nutrients are chemically
changed into forms unavailable to the plants. If the soil pH is too low
dolomitic lime should be applied to the field to raise the soil pH. The
advantage of dolomite over other forms of limestone is that in addition
to raising the pH and providing calcium to the plant, magnesium is also
supplied. As a rule of thumb approximately 1 ton/acre of pure lime
should be applied to raise the pH 1 unit on sandy soils of Florida.
Limestone should be applied approximately every 3 to 4 years, or when
ever the pH drops below 5.0.

Phosphorus and potassium should be applied according to the soil
test recommendation. In addition, micronutrients should also be applied
if the soil test shows the micronutrient levels to be low in the soil.
Though micronutrients are only used by the plant in small amounts, they
are essential for optimum plant growth. Micronutrients normally need to
be applied every 3-4 years. This of course should be determined by
annual soil testing.

Nitrogen is by far the major plant nutrient which stargrasses will
respond. Nitrogen application has a direct effect on yield and quality
of stargrasses. Recent studies at Ona have shown yields to increase
linearly as the amount of applied N increases up to 450 pounds/acre/year
(Table 1). In addition to increased yields, forage quality has also
been shown to increase with increased levels of applied N. As a general
fertilizer recommendation, 350 pounds/acre of a 16-8-16 fertilizer or
equivalent should be applied 3 times a year if the grass is going to be
intensively grazed. If the stargrass is going to be harvested for a hay
crop about 400-450 pounds/acre of a 15-15-15 fertilizer or equivalent
should be applied 4-6 weeks before each cutting. It should be
remembered that this recommendation would be modified depending on the
soil test results.

Until recently, little attention has been focused on the need of
sulfur fertilization for plant growth. This is understandable since in
the past fertilizers were contaminated with sulfur, thus there was not a
need to be concerned with sulfur fertilization. However, today in the
age of modern technology, fertilizer manufacturing processes have become
highly advanced and as a consequence fertilizers are free of sulfur
impurities. As a result, sulfur deficiencies are becoming more
pronounced throughout the world. When soils are low in sulfur, crop
yields, protein quality, and digestiblity may be reduced. Recent
results have shown sulfur application to increase the quality of
stargrasses. Thus, it may be advantageous to use a nitrogen source
containing sulfur such as ammonium sulfate especially when making grass
plantings on newly developed land from native conditions.

Research studies are currently being conducted to determine optimum
levels of N and the best pH for the growth of stargrasses on Florida
flatwood soils.

Table 1. Influence of nitrogen rate on yields of 'Cane Patch' and
'Puerto Rico' stargrasses in 1987.

'Cane Patch' 'Puerto Rico'
Nitrogen Yields Yields

Ib/A ----------tons/acre----------------
(split 3 times)

0 2.0 1.9
75 2.4 2.6
150 3.0 3.5
225 3.5 4.0
300 3.9 4.7
450 4.4 5.1
600 4.7 5.2

Field plots also received an annual application of 400 lb/acre 0-10-20.

Yields are a summation of 4 harvests in 1987.