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Effects of Stockpiling Initiation Date and Nitrogen Fertilization Rate on the Yield
of Stockpiled Bermudagrass Harvested Throughout the Fall and Winter
D. A. Scarbrough, 1 W. K. Coblentz, 1 K. P. Coffey, 1 J. E. Turner, 1
J. B. Humphry, 1 and K. F. Harrison 2
Story in Brief
Limited information is available that describes the DM yield potential of stockpiled bermudagrass [Cynodon
dactylon (L.) Pers.] during late fall and early winter. Well-established stands of ‘Common’ and ‘Tifton 44’ bermudagrass
at Fayetteville and Batesville, AR, respectively, were chosen to evaluate the effects of stockpiling initiation date and
nitrogen (N) fertilization rate on the dry matter (DM) yield potential of stockpiled bermudagrass forages throughout late
fall and early winter. At Fayetteville, DM yields of stockpiled bermudagrass initiated on August 8 decreased (P < 0.05)
between November 8 and November 29, but did not change (P > 0.05) between October 18 and November 8, or between
November 29 and January 8. Yields for forage that began the stockpiling period later (September 6) were highest (P <
0.05) on November 8. At Batesville, DM yields of stockpiled bermudagrass initiated on August 10 and September 6 followed
trends similar to those observed at Fayetteville. High temperatures and low moisture availability during the early
fall, in addition to an early killing frost and unusual weather patterns during the sampling period probably limited the
yield potential of stockpiled bermudagrass throughout the late fall and early winter.
Introduction
Beef cattle producers in Arkansas and the southeastern
US face many economic obstacles, one of which is feeding
mother cows throughout the winter. Many of these producers
rely on bermudagrass [Cynodon dactylon (L.) Pers.] as a primary
warm-season forage source during the growing season.
Bermudagrass has the potential to produce high forage yields
in response to fertilization with N (Doss et al., 1966; Hill et
al., 1993). This growth has traditionally been used to support
grazing livestock, but large quantities are also harvested as
hay which is subsequently fed during the late fall and early
winter after bermudagrass enters dormancy. However, costs
associated with hay production, and adverse weather conditions
during spring and summer make extended grazing systems
attractive to producers. Recently, winter-feeding systems
that involve stockpiling standing bermudagrass at the
end of the growing season have received increased interest.
Stockpiled bermudagrass can provide winter pasture for grazing
livestock, thereby reducing the need for supplemental hay
and its associated costs (D’Souza et al., 1990; Hitz and
Russell, 1998). However, most agronomic research studies
have focused on measuring DM yields of bermudagrass during
the growing season (Burton et al., 1963; Jolliff et al.,
1979). Little information is available that describes the DM
yield potential of stockpiled bermudagrass forages.
Therefore, the objectives of this study were to evaluate the
effects of stockpiling initiation date and N fertilization rate on
the DM yield potential of stockpiled ‘Common’ and ‘Tifton
44’ bermudagrass forages throughout late fall and early
winter.
Experimental Procedures
Well-established stands of ‘Common’ and ‘Tifton 44’
bermudagrass were divided into four blocks consisting of
eight plots each at Fayetteville and Batesville, AR, respectively,
in July 2000. Half of the plots in each block received
their final summer harvest on August 8 and 10 at Fayetteville
and Batesville, respectively; the remaining plots were harvested
for the last time during the growing season on
September 6 at both locations. These two final harvest dates
were used to create different initiation dates for autumn forage
accumulation, which ultimately resulted in different plant
ages throughout the accumulation and sampling periods of
the trial. Nitrogen fertilizer treatments (0, 33, 66, or 99 lb
N/acre) were applied as ammonium nitrate (34-0-0) to plots
on each initiation date. Forage growth was allowed to accumulate
until mid-October, when the sampling period of the
trial was initiated. Plots were sampled (2-in stubble height) in
3-wk intervals between mid-October and late-November to
determine DM yields. A fourth and final sampling date was
delayed until early-January due to poor weather conditions
that included substantial snow-fall events and subsequent
1 Department of Animal Science, Fayetteville
2 Livestock and Forestry Branch Station, Batesville
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