Final Environmental Impact Statement Rio de los Pinos Vegetation ...

Final Environmental Impact Statement Rio de los Pinos Vegetation Management Project
Alternative 1 – No Action
With no action, there is the potential for a short-term build-up of fuels on the forest floor and in
the canopies of the spruce trees as they begin to die. The first year or so after an Engelmann
spruce is infested by spruce beetle, the tree begins a slow drying process, brought about by the
larvae eating the phloem layer of the tree. During the second summer of an attack most needles
turn yellowish-green and begin to fall (Holsten et al. 1999). This period is when the potential for
large crown fires would be at its highest. After the needles have fallen the potential would
significantly decrease until many years later when there would be a greater potential for a heavy
build-up of fuels as the roots of snags begin to rot and snags begin to fall. As noted by Veblen
and others (1994) in some areas large outbreaks of spruce beetle and root rot in subalpine fir
have also resulted in heavy loadings of large woody fuels, which would support future standreplacement
fires. This could take from ten to thirty years or more. If fine fuels, weather
conditions, and ignition sources are available for a potential future fire event, the heavy fuels that
have fallen to the forest floor could increase the severity of the burn and possibly damage soils,
watersheds, and the ability of the area to regenerate.
Alternatives 2 and 3
Since the action alternatives allow for salvage harvest of the large diameter fuels (1000 hour
timelag fuels) and the slash left in the harvest units can be treated, this is the most ideal situation
for avoiding a severe fire event that could severely damage soils and the watershed. Contract
provisions allow for treating slash to make it less than 2 feet in height, creating fuels that are
more compact and part of the duff and litter layer. The only difference between the action
alternatives, as it relates to fire and fuels management, would be in the acreage treated by
salvage.
Alternative 2 would have the most positive effect on fuels and fire management from the
standpoint that it is the largest acreage treated with some sort of harvest activity. Removing trees
infested with spruce beetle and the resulting slash treatment would remove the largest amount of
potential fuels from the stands. However, it would not serve to eliminate the potential for a stand
replacement fire, because even a low intensity surface fire in spruce-fir can cause high
percentages of mortality.
Alternative 3 would concentrate its treatment to only the infested areas in the center portions of
the analysis area and eliminating areas with high stream concentrations. This would key in on the
concern at hand by treating the fuels generated by dying trees and then subsequently treating the
slash in areas proposed for harvest, but not within areas around streams, thus leaving the area at
risk for a wildfire damage soils due to high concentrations of fuels remaining on site.
Cumulative Effects:
There is a risk of a future fire impacting the analysis area in the short term following treatment.
This increased risk of wildfire could increase the potential danger to life and high-value property,
both on private and federal lands. With the high density of dead and live material adjacent to and
within the analysis area, a favorable environment exists for ignition and rapid spread of wildfire
during periods of extremes in temperature, winds, and low fuel moistures.
Chapter 3 – Affected Environment & Environmental Consequences Page 3-98