ENVIRONMENTAL CONSEQUENCES in rocky mountain coniferous ...

Control Chapped Picked up Broadcast Piled and Piled and
and and Burned Burned Burned
Spread Removed (~n rows) (between row)
LOGGING RESIDUE DISPOSAL TREATMENTS
Figwe 3.--Organic matter content of the surface Z-inches of soil associated with
- various residue treatments on lo&epo2e pine cZearcuts.
P H
The effects of the residue tfeatments on the pH of the surface 2-inches of
soil are shown in figure 4. The only signi ficant chanae was the increase
in pH associated with burning windrowed residues. ~hese windrowed residues
burned hotter than the broadcast residues. The increased pH is attributed to the
release and concentration of both monovalent and divalent cations and nitrates
as the residues are oxidized by fire. These increases have persisted throughout
the 4-years since the windrows were burned.
VEGETATIVE COVER DENSITY
Effects on Vegetative Characteristics
The effects of logging and residue treatments on the density of vegetation
covering the ground are shown in figure 5. Prior to logging, total cover density
at the ground surface (including plants, litter, and logging residue) was similar
to that on the unlogged control tracts--about 99 percent. Because the density of
vegetative cover on the logged units was already nearly complete, even the
addition of large quantities of residue had little effect on total cover density
measurements, increasing them, on the average, less than 1 -percent. Following
logging, the cover densities of those blocks where residue was chipped and
respread were still about 100-percent, although the cover was mainly chips rather
than plants and litter. This cover of chips was still intact in 1977, 4-years
after spreading.