FIRE EFFECTS
SPECIES: Rudbeckia hirta | Black-Eyed Susan 



IMMEDIATE FIRE EFFECT ON PLANT : 
Black-eyed Susan is probably top-killed by fire during the growing
season.  It may survive by sprouting from the root crown [56].


DISCUSSION AND QUALIFICATION OF FIRE EFFECT : 
NO-ENTRY


PLANT RESPONSE TO FIRE : 
Black-eyed Susan does not respond uniformly to burning.  Depending on
season of burning and local conditions, it often establishes
successfully; existing populations may either increase or decrease in
abundance.

In south-central New York wildfires burned goldenrod (Solidago spp.)-
poverty oatgrass (Danthonia spicata) fields in the springs of 1962,
1963, and 1964.  Adjacent burned and unburned areas were measured for
vegetative response 10 to 26 months after the fires.  The average
frequency of black-eyed Susan in unburned areas was 29 percent; in
burned areas it was 2 percent [54].

In southwestern Missouri after a decade of prescribed burning on glade
grasslands black-eyed Susan had decreased in abundance [42].

Black-eyed Susan seeds were broadcast in the fall of 1988 on sites in
tallgrass oak savanna in northwestern Illinois.  Consecutive spring
prescribed fires were conducted in 1989, 1990, and 1991.  By the fall of
1991 there were both seedlings and mature plants of black-eyed Susan on
burned sites [9].

Black-eyed Susan decreased with repeated dormant season prescribed fire
on one test plot in south-central Wisconsin, but increased every year in
another field subjected to the same treatment [39].

In south-central Wisconsin the Curtis Prairie has had a biennial burning
schedule since 1950, one-third being burned one year and the other
two-thirds the following year.  Black-eyed Susan was not present in
1951, but had appeared in small numbers by 1961.  An extended growing
season on the burned prairie appears to enhance presence of black-eyed
Susan.  During the spring, daytime temperatures are substantially warmer
on the burned than on the unburned prairie, where the litter layer
retards soil warming.  The burned surface also cools faster at night.
These effects are most pronounced in May and June [2]

Black-eyed Susan in tallgrass prairie in eastern Nebraska on silty clay
loam was burned in early May, early July, and mid-September, 1983.
Plots were sampled in the fall of 1983, 1984, and 1986.  Burning,
particularly summer and fall burning in years with adequate
precipitation, resulted in higher black-eyed Susan seedling
establishment than occurred without burning.  In dry years burning
reduced seedling establishment.  Black-eyed Susan cover also increased
with summer and fall burning; cover decreased without burning [7].

Black-eyed Susan on a poor condition prairie range site in north-central
Oklahoma was burned April 1, 1965-1967, in conditons where the soil was
moist and the fire burned against a 5 to 10 mile-per-hour (8-16 k/h)
breeze.  Matched unburned plots were mowed earlier in the spring, and
the residue removed.  In the spring of 1966, black-eyed Susan flowered
profusely on unburned plots, but was absent on burned plots [27].


DISCUSSION AND QUALIFICATION OF PLANT RESPONSE : 
NO-ENTRY


FIRE MANAGEMENT CONSIDERATIONS : 
NO-ENTRY

Related categories for Species: Rudbeckia hirta | Black-Eyed Susan