FIRE EFFECTS
SPECIES: Panicum hemitomon | Maidencane 



IMMEDIATE FIRE EFFECT ON PLANT : 
Maidencane grows in wet to moist areas where its rhizomes are generally
protected from damage by fire when aerial portions burn [48]. 

In the upper Everglades area, fires which occur during normal
hydroperiod cycles, when water levels do not recede more than 4 or 5
inches below the surface of the ground, have a positive effect on
maidencane.  It recovers very rapidly and grows more vigorously than
prior to burning.  During extreme drought periods, water levels may
recede 3 or 4 feet below the surface of the ground.  Then fire destroys
not only the aerial vegetation but also the upper, dry, compacted peat
layers to a depth of 3 or 4 inches and up to a foot or more in localized
areas.  Maidencane is killed when its rhizomes are burned [29]; whether
death occurs is determined by depth of rhizomes and depth of burning.


DISCUSSION AND QUALIFICATION OF FIRE EFFECT : 
NO-ENTRY


PLANT RESPONSE TO FIRE : 
Maidencane grows quickly from rhizome buds following a growing-season
fire in which rhizomes are not injured [27].  It can sprout within 3 or
4 days after burning [29].  Significant growth of maidencane occurs
within 1 month after fire, and often within 6 months density is as great
as before fire.  However, the fire's impact depends on how fast and how
deeply the organic soil burns and how slowly the water level rises after
the fire [27].  In a greenhouse study using maidencane from South
Carolina freshwater wetlands, inundation reduced maidencane growth after
fire.  Rhizomes from plants that had been recently burned and from those
that had not were grown in four water level treatments:  (1) permanently
inundated soil; (2) inundation followed by moist soil; (3) saturated
soil; (4) moist soil.  Burning reduced stem numbers and stem height of
maidencane in the first and second treatments and had no measurable
effects in the remaining two treatments [25].

During the growing season after fire, maidencane sprouts earlier and
more thickly on burned than on unburned sites.  It also flowers earlier.
Fire stimulates seedstalk production and yields [49].

On Gannet Pond in northern Leon County, Florida, maidencane that had
been burned a month before while dormant produced green shoots the third
week in February 1971.  In the first week of March, maidencane was 4
inches (10 cm) tall.  By the end of April it was 24 inches (60 cm) tall.
Inflorescences were present by the first week in May.  Maidencane in the
unburned control section did not produce green shoots until March 15,
and inflorescences did not appear on unburned shore line until May 11
[48].


DISCUSSION AND QUALIFICATION OF PLANT RESPONSE : 
The north shore of Gannet Pond, a man-made impoundment in northern Leon
County, Florida, was burned during the winter of 1969-70.  An
experimental section was burned again on January 21, 1971, under
conditions which closely simulated a severe wildfire.  A line of fire
was spread along the water's edge and moved as a headfire 60 feet (18 m)
from open water into timber.  Fire also backed toward the open-water
edge in the emergent aquatic growth.  After treatment, maidencane was
taller, more robust, and more dense in the burned area.  The greatest
difference in yield between unburned and burned vegetation was found in
the drier portions of the grassy zone, where a 15-inch (37-cm) mat of
the previous year's maidencane growth suppressed new growth in the
unburned area [48].

In the upper St. Johns Basin in east-central Florida, maidencane marshes
have expanded at the expense of sawgrass marshes following deep-burning
fires.  They now cover 37 percent of the headwater wetlands [27].


FIRE MANAGEMENT CONSIDERATIONS : 
Maidencane can be burned to improve wildlife habitat and range [50].
The burning of maidencane along shorelines usually leaves areas of
litter, stubble, "rough", and unburned vegetation which provide cover
for some species, while improving food sources for others [48].

Maidencane-cattail marsh in southeastern Louisiana can be burned in late
winter just before the start of the spring growing season to encourage
food plants for muskrats and waterfowl.  If this marsh remains unburned
for more than 2 or 3 years, maidencane overwhelms more valuable food
plants [31].

In Leon County, Florida, recently burned maidencane sites were preferred
to unburned sites by many animal species for 4 months after fire.
Common moorhens, purple gallinules, and eastern kingbirds preferred
burned sites as territories and probably for nesting sites.  Great
egrets, great blue herons, little blue herons, and snowy egrets were
more frequently found on burned than on unburned sites, possibly because
they were attracted by the shallow flats on the burned shore line.
Mourning doves and common snipe were most common on the fresh burns,
where the newly exposed ground made food more available.  American
alligators used the burned shore almost exclusively [48].

Surface fires do not affect the vegetational structure of a marsh if
standing water protects the basal parts of perennial plants [41].
Controlled burning produces favorable results for maidencane except when
burning is conducted late in the growing season or under unusually dry
conditons that result in ground or peat fires which destroy rhizomes
[48].  There should be at least an inch of standing water at the time of
a prescribed fire to prevent root burns, which occur in peaty marshes
burned during drought conditions.  Root burns kill maidencane and allow
invasion by earlier successional species [41].

Maidencane disappears when fire exclusion allows woody vegetation to
invade wetlands [23].  Fire was excluded from some southwestern Florida
maidencane habitats from 1939 to 1968.  In that time forest and shrubby
vegetation invaded; in the areas of invasion maidencane disappeard [23].
In Florida, shallow maidencane marshes can be completely replaced by
woody thickets within 5 to 10 years.  Relatively frequent fires help
maintain Florida marshes [27].

In Sarasota and Manatee counties, southwestern Florida, prescribed fire
in dry conditions early in the growing season is more effective in
reducing woody species cover than are dormant-season fires or later wet
growing-season fires [23].

Maidencane occurs in open marsh areas of the Okefenokee Swamp, but not
in the 80 percent of the swamp covered with forests of pondcypress
(Taxodium distichum var. nutans) or swamp tupelo (Nyssa sylvatica var.
biflora).  The open marshes are the result of very severe fires which
have killed woody growth and burned away the upper part of the peat bed.
Maidencane then invades the marshes.  In the absence of severe fires
accompanying extreme drought, these marshes gradually revert to swamp
forest through the formation and expansion of clumps of trees and shrubs
[7,8].

Maidencane in Corkscrew Swamp Sanctuary in south Florida grew in sites
that had been logged (1954), burned (1962), or logged and burned (1954
and 1962).  Maidencane importance value (the sum of relative dominance,
relative abundance, and relative frequency) was recorded between
November 1975 and September 1976; importance value was highest (35.5) at
the site that had been burned only.  Importance value was 8.3 and 1.5 on
two logged sites.  Maidencane was not present where the land had been
both burned and logged, probably because of the severity of soil
disturbance and exposure of the organic layer [18].

The lowering of the water table and the shortening of the hydroperiod in
drained areas of Florida have contributed to more severe wildfires which
have burned out surface layers of peat.  Most of the resulting
depressions have changed to wet prairies; the lengthening of the
hydroperiod in these depressions has resulted in displacement of
sawgrass by associations including maidencane.  Maidencane flats are
becoming more widespread partly because maidencane can tolerate both
recurrent fire and widely fluctuating water levels [50].

Related categories for Species: Panicum hemitomon | Maidencane