FIRE EFFECTS GUIDE - National Wildfire Coordinating Group

Bunting et al. (1987) suggest that selection of area to be burned will dictate many
of the economic variables such as fire prescription and characteristics and whether
it achieves its objectives . . . the higher potential sites produce the highest benefit.
He also states that burning during the spring with snow lines and increased fuel
moisture on varying aspects adjacent to the proposed treatment area may aid in
fire control and reduce overall cost. The limited burn size, however, may increase
the amount of time and personnel required for ignition resulting in higher average
costs per acre or not achieving the planned objectives. Bunting says that
economics is also a factor in determining the size of fires. The costliest portion of
conducting prescribed fires is establishing and burning out the fire lines. The
smaller the size, the greater the perimeter per unit area. Without natural fuel
breaks, an extensive system of fire lines may have to be established to restrict the
fires to the desired size. This often makes the prescribed burns economically
unfeasible.
From an economic standpoint, spring burning is cheaper as it can be accomplished
with fewer individuals and without firebreaks in some situations (Blaisdell et al.
1982). West and Hassan (1985) state that the highest potential for prescribed
burns is on sites in good condition. Haslem (1983) provides several guidelines to
maximize returns from burning including realistic prescriptions, treating
manageable units, using livestock use for controlling escapes, use of natural
control barriers, and use of test burns. Smith (1981) states that followup
management is essential in extending the fire's useful lifetime.
Young and Evans (1978) state a general rule that one must be able to step from
one bunch grass plant to another to have a reasonable chance of enhancing the
site by recovery of existing plants. Bunting (1984) also notes the bluebunch
wheatgrass response is from existing plants for the first 3 or 4 years after a fire.
Dramatic increases in numbers of plants of exotic annual species can occur after
fire, particularly if the existing bunchgrass community was in poor condition or
many of the plants were killed by the fire. This potential for site invasion must be
considered along with the above guidelines when deciding if a site can recover
without artificial seeding.
5. Examples of Different Intensities of Grazing Management. Many different
grazing management strategies have been implemented after burns, however, few
have been intensively monitored to determine their impacts on fire effects. Two
prescribed burns in northwest Wyoming, which escaped into adjoining grazing
allotments, were monitored during 1987 to provide data on effects of postfire
grazing management on vegetative response.
a. Blue Creek Coordinated Resource Management Plan (CRMP). In 1984, the
operators agreed to a CRMP with the Wyoming Game and Fish Department and
the Bureau of Land Management. The area is located south of Meeteetse,
Wyoming, in the 15 to 19 inch (38 to 48 centimeters) precipitation zone at the 7,800
foot (2,377 meters) elevation. The vegetation type is composed of limber pine
(Pinus flexilis) and mountain big sagebrush (Artemisia tridentata vaseyana) on a
shallow loamy range site. Key graminoid species include Idaho fescue (Festuca