ENVIRONMENTAL CONSEQUENCES in rocky mountain coniferous ...

Control Chjpped Plcked up Broadcast Piled and Piled and
and and Burned Burned Burned
Spread Removed (in rows) (between rows)
LOGGING RESIDUE DISPOSAL TREATMENTS
Figure 8.--SoiZ erosion Losses associa$ed with various residue krea&mmts on
ZodgepoZe pine ctearcuts during 30 minutes of infiltromeker rainfall at; 3.25
inches per hour.
CONCLUSIONS
The results of this study show that the residue disposal treatments employed
on these tracts produced changes in surface soil and vegetative characteristics--
changes that sometimes enhanced and sometimes impaired the hydrologic performance
and soil stability behavior of the lodgepole pine sites. In general, the recovery
of impaired watershed protection conditions does not occur rapidly given the
high altitudes and the short growing seasons that characterize these forests.
Furthermore, recovery of impaired conditions appears somewhat slower on sites
where the vegetation and soil mantle have been drastically disturbed by mechanized
equipment than on similar sites where residue disposal did not disturb the forest
floor.
The most effective residue treatment in terms of surface runoff and erosion
control is the chipping and respreading of the residue as a protective mulch.
This particular treatment, however, has serious di sadvantages--the almost complete
suppression of vegetation and the elimination of natural lodgepole pine reproduction.
The most adverse soi 1 and vegetative characteristics, the poorest surface
runoff and erosion control, and the slowest recovery rates were encountered where
residue was dozer piled and burned.