FIRE EFFECTS
SPECIES: Cynodon dactylon | Bermuda Grass 



IMMEDIATE FIRE EFFECT ON PLANT : 
Fire top-kills Bermuda grass but rhizomes probably remain undamaged
except during severe fire that burns organic soil [80].  Cultivars that
are strongly stoloniferous may be more damaged by fire than those that
are predominantly rhizomatous [62].  Soil- or litter-stored Bermuda
grass seed did not germinate after litter was removed by fire; seeds may
have been destroyed by fire [29].


DISCUSSION AND QUALIFICATION OF FIRE EFFECT : 
NO-ENTRY


PLANT RESPONSE TO FIRE : 
Bermuda grass productivity and cover have both increased and decreased
after early spring fires.  Bermuda grass response depends on postfire
moisture conditions and nutrient levels [34,56,57,63].

Four treatments (fertilized, burned in early April, burned and
fertilized, and control) were applied to an Oklahoma grassland of
prairie threeawn (Aristida oligantha), Bermuda grass, little bluestem
(Schizachyrium scoparium), and paintbrush bluestem.  Bermuda grass cover
increased significantly (P<0.05) over control levels with fertilization
and the burning-fertilizing combination, but increased only slightly
with burning alone.  The burning-fertilizing treatment resulted in
slightly higher cover than the fertilized treatment [63].

A March 5 fire on a Georgia old field resulted in a decrease in Bermuda
grass yield.  The control produced 14.7 grams per square meter and the
burned area produced 0.24 gram per square meter in the summer after the
fire.  Bermuda grass was a minor species on the site [60].  Postfire
moisture conditions were not reported.

No change was detected in Bermuda grass cover after a dormant season
fire in a mid-grass community in Serengeti National Park, Tanzania,
Africa [5].

Spring burning stimulates seed production of Bermuda grass.  In Georgia
Bermuda grass burned on March 29 produced 46 pounds of seeds per acre
compared to 16 pounds per acre on the unburned control.  The following
year the site was burned on April 15, and Bermuda grass produced 29
pounds per acre on the burn compared to 3 pounds per acre on the control
[13].


DISCUSSION AND QUALIFICATION OF PLANT RESPONSE : 
NO-ENTRY


FIRE MANAGEMENT CONSIDERATIONS : 
Early spring prescribed burning is regularly used in Bermuda grass
pastures to remove old stubble and manure, reduce insects and disease,
control woody sprouts, and reduce weeds [34,36,45,56,57,62].  Prescribed
burning of Bermuda grass may control leaf spot and stem blight caused by
Helminthosporium spiciferum and H. rostratum [36].  Hamilton [34]
recommended burning only in years with sufficient soil moisture to
promote rapid postfire growth.  However, in areas with high rainfall (30
to 40 inches [760-1,020 mm]) or where irrigation is available, burning
can be done on an annual basis [34].  Pinkerton and Rice [62] reported
that some cultivars can be burned as often as needed with either
headfires or backfires.  Burning should take place while plants are
still dormant.  The recommended time is 1 week before the average date
of the last killing frost [34,56].

Average dry matter yield of Bermuda grass pasture burned March 1 in
Georgia was 832 pounds per acre (1,000 kg/ha) higher than yields of
unburned controls.  Digestibility and crude protein content of the
Bermuda grass were not affected by burning.  Because of an increase in
absorbed solar radiation, burning increased the soil temperatures at 1-,
2-, and 4-inch (2.5, 5, and 10 cm) depths for 2 to 3 weeks after
burning.  Dry matter yields were positively related to soil
temperatures, but the relationship was subject to the modifying
influences of rainfall, air temperature, and soil fertility [56].

Morris [57] reported that burning Bermuda grass pastures had differing
effects on forage yields depending on fertilization levels.  Yields
increased by 1,017 pounds per acre (1,140 kg/ha) after annual spring
burning followed by a high level of fertilization on a Georgia site, but
yields remained unchanged with medium and low levels of fertilization.
Burning reduced weeds regardless of fertilization level.  Burning on
April 1 provided better weed control than burning on January 1 or March
1 [57].

The effects of fire on Bermuda grass yield vary among cultivars.
Pinkerton and Rice [62] investigated the effects of annual March
backfires and headfires on the yields of six Bermuda grass cultivars.
After 3 years of annual burning, yields of `Coastal,' `Common,'
`Brazos,' and `Tifton 44' were unaffected by either backfire or
headfire; `Tifton 78' was reduced by backfire only; and `Grazer' was
reduced by both backfire and headfire.  Fire-related yield reductions
occurred during only the first two of the five yearly harvests.  Yield
reductions appeared to be related to how stoloniferous the cultivar was,
with the more stoloniferous cultivars showing greater reductions,
particularly when burned with backfires which traveled more slowly than
headfires [62].

Spring burning prior to urea application may decrease the amount of
gaseous ammonia lost when urea reacts with organic matter.  In a Georgia
study Bermuda grass yields from fields burned and fertilized with urea
did not differ significantly from fields fertilized with ammonium
nitrate fertilizer [45].

Related categories for Species: Cynodon dactylon | Bermuda Grass