ENVIRONMENTAL CONSEQUENCES in rocky mountain coniferous ...

+
In the Lake States Simmons and others (1977) determined that prescribed burning
to control the maple leaf cutter Paraclemensia acerifol iella (Fitch)), which pupates
in the forest floor, was more effective t an insecticide treatments.
RESIDUE AND FIRE MANAGEMENT--SOME OPINIONS
Since the early 19001s, there has been an evolution in philosophy and strategy
concerning the management of forest residues. Two issues are involved: 1) residue
management and utilization as it involves protection from wildfire, and 2) residues
triggering forest Insect and disease outbreaks.
In the early 19001s, Mitchell (1913) indicated that in California the piling
and burning of residue was the accepted method because of 1) a desire to render the
cutover area as fireproof as possible, 2) the belief that protection of litter was
not necessary to insure reproduction, and 3) a desire to make the area as sightly as
possible. There was considerable controversy as to whether the increased protection
from wildfire by prescribed burning offset the danger involved, the expense, and the
damage to reproduction and standing timber.
The issue of the expense of burning forest residue was echoed the following
year by Koch (1914) in the northern Rocky Mountains. Citing examples on the Lolo
National Forest in western Montana, Koch 1) questioned the risk (to wildfire) of
unburned residue, and 2) chided the Forest Service for "...piling brush just because
we have always piled brush.. . ," adding, "it is time for us to quit blindly following
precedent and at least make a serious investigation of the possibility of less
expensive methods of protection. "
Shortly thereafter, Hopping (19151 acknowleged Mitchell 's and Koch's concerns
about protection and cost-benefi ts, but mentioned another protection aspect--the
dangers of insect infestations that can result fr~m destructive insects breeding in
unburned forest residues. Citing several examples to support his point, Hopping
concluded by saying that ".,.the consideration of the burning or non-burning of
brush must be taken up from a broad protection standpoint and not from the standpoint
of fire risk or cost alone."
Later, in studying residue management in the lake States, Mitchell (1921 )
advocated intensive rotection rather than prescribed burning. He felt that destroying
the residue E y burning did not mqterially reduce the fire hazard because
1) of the 1 itter accumulati~n normally present and 2). the close utilization of cedar
and spruce for pulp and posts resulted in 1i.ttle reslde created. Moreover, Mitchell
belieyed that prescribed burning actually increased the fire hazard by killing, but
not c~nsuming, reproduction, as well as damaging or destroyfng the soil organic
1 ayer.
The following year, Graham (1 922) discussed the entomologicql aspect of the
residue management problem, and pointed out that 1) "...we are burning up valuable
humus in our slash piles," 2) smaller pieces of residues are unfavorable to insect
deyelopment, while lar er branches, tops and broken logs are the most suitable
breedlng plqces, and 3 3 larger pieces of residue aye more difficult to burn, do not
materially increase the danger of wildfire, and after burning usually remain on the
ground uncharred. Graham (1922) concluded that in the Northeast prescribed burning
is not the best way to manage residue, nor can it be recomnended or is ". . .as effec-
tive a factor in forest insect control as has been generally be1 ieved."