ENVIRONMENTAL CONSEQUENCES in rocky mountain coniferous ...

Considering the planned and unplanned modifications to the study plan, our study
design was based around four combinations of harvesting and residue treatments and a
control, as fol 1 ows :
Si 1 vicul tural
Treatment Prescription Block # Residue Treatment Subunit
1 Cl earcut 2 3 Residues burned 1
2 Cl earcut 23 Residues mechanically removed 3
3 She1 terwood 21 Residues burned 1
4 She1 terwood 21 Residues mechanical l y removed 3
5 Undisturbed forest 24 None 5
Sampling Design and Plot Layout
To facilitate the pre- and post- harvest sampling activities of all the involved
disciplines and studies, a permanent plot location system was established on each of
the cutting blocks. Permanent points were systematically located at 30.5 meter
(100 ft) Interyals within each of the subunits in the clearcut and shelterwood blocks
and at variable intervals within each of the eight group selection cuts, Twenty
potnts were also established in each control area, Blocks 14 and 24.
For our entomological work, we randomly selected from the permanent plot location
system three plots in each of the four treatments. The plots were randomly selected
with the exception that in treatments 1 and 3, if the plot initially selected was
missed by the prescribed fire, the random selection procedure continued until a plot
was selected that had, in fact, been burned.
Fi el d and Laboratory Procedures
Sampl ing began at the study area in September 1975 and continued through August
of 1977. At each sampling period, one sample was taken from each of the plots, for a
total of 15 samples over the 5 treatments. The sampl ing dates were as follows:
1975 1 September
1976 4 June
20 June
2 July"
21 ~ u l y ~
4 August
19 August
6 September
14 September
1977 19 July
29 August
'No samples were drawn in she1 terwood treatments 3 and 4 in July.