Wildlife, Animals, and Plants
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FIRE EFFECTS
SPECIES: Sassafras albidum | Sassafras
IMMEDIATE FIRE EFFECT ON PLANT :
Low-severity fires kill seedlings and small saplings. Moderate- and
high-severity fires injure mature trees, providing entry for pathogens
[41,75]. In oak savanna in Indiana, sassafras showed significantly less
susceptibility to low-severity fire than other species [4]. Sassafras
exhibited 21 percent mortality of stems after prescribed fire in western
Tennessee. This was the lowest mortality of all hardwoods present.
Season of burning did not affect susceptibility [17].
DISCUSSION AND QUALIFICATION OF FIRE EFFECT :
NO-ENTRY
PLANT RESPONSE TO FIRE :
Sassafras occurs on charcoal hearths, which are patches of ground that
were used for charcoal making. These areas are characterized by very
poor soil structure. Sassafras on these sites shows poor growth [10].
The effects of annual and 5-year interval prescribed burning over a
27-year period in Tennessee has been reported. After 6 years, sassafras
density was higher on annually burned plots than on unburned plots. The
highest sassafras density occurred on the 5-year interval plots [80].
Sassafras gradually decreased with increasing canopy closure on the
5-year interval plots. By year 27, however, sassafras was eliminated
from the annually burned plots. Sassafras was also eliminated from
unburned plots; these plots developed closed canopies which are
unfavorable to sassafras [19].
A large number of root sprouts occurred after sapling and small diameter
sassafras trees were top-killed by fire in an Illinois post oak (Quercus
stellata) stand [12]. Sprout production by top-killed sassafras was
stimulated by prescribed fire, and greatly increased its cover in the
shrub layer [13].
In Illinois, the number of small sassafras stems increased after a
single winter prescribed fire from 9 percent frequency to 36 percent
frequency. This increase was largely due to root sprouting by
top-killed plants. The number of sassafras seedlings also increased
after the same fire [3]. In Virginia, in Table Mountain pine stands
that experienced a high-severity wildfire (98 percent top-kill),
sassafras increased from 0 to 12.1 in relative importance in 1 year.
Sassafras also increased on plots experiencing low-severity fire, but the
difference in importance value was not as great [42].
In the absence of fire or other disturbances, sassafras frequency
decreases with increasing canopy closure; the number of new sassafras
seedlings also decreases with canopy closure [2,3].
Fire does not always lead to increased sassafras. Grelen [40] reported
sassafras occurrence on unburned, young slash pine (Pinus elliottii)
plots but not on plots burned annually, biennially, or triennially in
March or May over the course of 12 years. In Florida, sassafras was
found on unburned, 15-year-old old fields, but not on oldfield plots
that were burned annually in February or March for 15 years [26].
DISCUSSION AND QUALIFICATION OF PLANT RESPONSE :
NO-ENTRY
FIRE MANAGEMENT CONSIDERATIONS :
Prescribed fire for hardwood control in southern pine stands results in
the predominance of American beautyberry (Callicarpa americana) and
sassafras. This predominance is a useful indicator of temporary control
over other hardwoods that usually occupy later seres and are more
serious competitors of pine. Prescribed fire at 8- to 12-year intervals
can control sprout growth or new plant invasion [74].
In South Carolina, a prescribed January fire in loblolly pine increased
sassafras browse quality and availability. Prior to the fire, sassafras
stems were out of reach of white-tailed deer [21]. The protein content
of sassafras leaves and twigs was highest in June following prescribed
fire. By September, the protein content of all browse plants was
similar on burned and unburned sites [23]. After logging and
presecribed burning in an oak-pine stand in South Carolina, white-tailed
deer browsed sassafras heavily [27].
Frequent prescribed fire can improve spring and summer forage quality in
the southern pine forests, where sassafras often occurs.
Prescribed fire on utility rights-of-way does not control sassafras [5].
Vigorous root sprouting maintains sassafras even after repeated fires.
Annual prescribed fire, however, may have a detrimental effect on
sassafras fruit production [50]. On some sites, repeated annual fires
may eventually eliminate sassafras [19,26,40].
A regression equation to calculate the relationship of sassafras bark
thickness to stem diameter has been reported [46]. An equation for
predicting standing sassafras dry weight (and therefore fuel loading)
from sassafras basal diameter has also been reported [70].
Related categories for Species: Sassafras albidum
| Sassafras
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