ENVIRONMENTAL CONSEQUENCES in rocky mountain coniferous ...

STUDY AREA
General
The study focused on the Corarn Experimental Forest (CEF) , located approximately
9 miles (14.5 km) east of Columbia Falls, in northwestern Montana. Latitude is
approximately N 48" 25' and longitude W 114" 00'. The CEF (part of the Flathead
National Forest) encompasses 7,460 acres (3,019 ha), 811 acres (328 ha) of which are
set aside as a natural area. Elevations range from 3,500 to 6,300 feet (1,067 to
1,920 m). Mean annual precipitation in the central (~bbot Creek) basin is 35 in (89
cm). The mean annual temperature is 42°F (5.6"C). The western larch/Douglas-f ir
forest cover type predominates. Average number of trees per acre, mean d. b. h., and
mean height for tree species (based on sarnpl ing units total 1 ing 80 acres (32.4 ha))
on typical sites in the CEF are shown in table 1. Timber, terrain, soils and wildlife
are representative of many areas in western Montana and northern Idaho. More
detailed descriptions of various environmental parameters on the CEF study site are
given later in this paper or have been presented in earlier papers in this symposium.
TABLE 1 .-- Number of trees (4 9 in (23 cm) d. b.h. ) per acre based on total sample of
80 acres (32.4 ha), CEF.
Tree species Trees per Relative Mean dbh Mean height
acre (ha) density (%) in (cm) ft (m >
Douglas-f ir
Subalpine fir
Engelmann spruce
Western larch
Western hemlock
Lodgepole pine
Western white pine
Western redcedar
All woodpecker feeding observations and general bird censuses were done on the
CEF, primarily in and near units harvested in 1974. We searched for active nest trees
on the CEF and other areas of the Flathead National Forest, and in Glacier National
Park.
1974 Harvesting Treatments
Two sets of timber harvesting units were logged in 1974 by the sky1 ine method.
In each set, in this report termed the lower units (average elevation approximately
4300 ft (1311 m) and higher units (average elevation approximately 5030 ft (1534 m))
there were control, she1 terwood, group selection, and clearcut units. Unit treatments
were as follows:
CONTROL: No manipulation. Uncut forest adjacent to cutting units was sampled.
No precise boundaries were deslgnated in the controls.
SHELTERWOOD: About 50% of the merchantable timber was removed in 1974. The
remainder is to be removed after a new stand becomes established. Lower unit:
34.1 acres (13.8 ha). Higher unit: 21 -5 acres (8.7 ha).