FIRE EFFECTS
SPECIES: Quercus nigra | Water Oak 



IMMEDIATE FIRE EFFECT ON PLANT : 
Water oak is easily damaged by fire [50].  Low-severity surface fires
top-kill water oak less than 3 to 4 inches (7.6-10.2 cm) in d.b.h.  The
bark of larger trees is thick enough to protect the cambium from
low-severity fires and the buds are above the heat of the fire.  In a
study on the Santee Experimental Forest in South Carolina, periodic
winter and summer low-severity fires and annual winter low-severity
fires were effective at reducing the number of hardwood stems (including
water oak) between 1 and 5 inches (2.6-12.5 cm) in d.b.h.  Annual summer
fires also reduced the number of stems in that size class, as well as
nearly eliminating all stems less than 1 inch (2.5 cm) in d.b.h.  Root
systems were weakened and eventually killed by burning during the
growing season [53].
    
The mean time in seconds for water oak cambium to reach the lethal
temperature of 140 degrees Fahrenheit (60 deg C) when a standardized
flame was applied to living bark was 30.2 seconds for 0.2 inch-thick
(0.5 cm) bark, 61 seconds for 0.3 inch-thick (0.8 cm) bark, and 136
seconds for 0.4 inch-thick (1 cm) bark [17].


DISCUSSION AND QUALIFICATION OF FIRE EFFECT : 
NO-ENTRY


PLANT RESPONSE TO FIRE : 
Water oak, including seedlings, sprout from the root collar if
top-killed by fire.  Larger water oaks that survive fire but have fire
scars are extremely susceptible to butt and heart rot [50].  After being
fire scarred, the average rate of spread of rot in water oak is 1.25
feet (0.4 m) per decade [46].


DISCUSSION AND QUALIFICATION OF PLANT RESPONSE : 
NO-ENTRY


FIRE MANAGEMENT CONSIDERATIONS : 
Hardwoods growing within a pine forest are often controlled with
prescribed fire.  Water oaks up to 3 inches (7.6 cm) in d.b.h. are
top-killed and sprouts kept small and controllable with prescribed
winter fires.  Summer fires are also effective but are more detrimental
to the wildlife food supply [5].  Herbicides combined with fire can be
used to eradicate larger water oaks [51].

Because water oak leaves and habitat are often moist, fuels should be
allowed to dry at least 3 weeks following a rain of 0.5 inch (1.3 cm) or
more.  Some fires will not carry even under ideal conditions of less
than 4 percent fuel moisture, 20 to 30 percent relative humidity, and 2
miles (3.2 km) per hour winds within the stand [42].

Burning has only a slight effect on the quality of water oak browse.  In
one study, protein was slightly higher and phosphoric acid slightly
lower on burned plots than on unburned plots [26].

Related categories for Species: Quercus nigra | Water Oak