ENVIRONMENTAL CONSEQUENCES in rocky mountain coniferous ...

At Coram, steep harvested slopes had a much longer frost-free period (based on
air temperature) than did the local creek bottom (fig. 21) or two nearby valley
stations (Hungry Horse and West Glacier). In the clearcut, radiation cooling of
surfaces depressed minimum temperatures compared to those of the uncut stand.
Clearcuts received freezing temperatures 10 days sooner than uncut areas, but 30 days
later than the local creek bottom. Differ~nces were not nearly as great as at
Lubrecht, At Solo Creek, 1 i ke Coram, freezing temperatures in midsummer were not a
problem, although clearcutting did decrease the number of frost-free days (fig. 22).
CLEARCUT
SHELTERWOOD
F?&ww 21.-- mber of days to the first frost in the cutting iSreaemeni4s foZZowing
the first post in *ha old cZeareut beZow the treatments. Based on air temper-
atures at Corm in 1976.
RES l DUE LEFl CLEARED UNCUT
Figure 22. -- h'umber of frost-free days in 1978 by cutting a7zd residue treatment,
So20 Creek. Temperatures of -1'~ or less at the swface are defined as
frost.
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