VEGETATION 



FIGURE III-l — HISTORIC, CURRENT, AND 

 APPROPRIATE DISTRIBUTION COVERTYPB 

 DISTRIBUTION IN ANALYSIS AREA 



COVERTYPE DISTRIBUTION IN 

 HISTORIC FLATHEAD VALLEY 



Lodgepole pine 27% 



Mixed Conifer 6% 

 1% 

 Douglas-fir 1% 



28% Western larch/ 

 Douglas-fir 



1% Western 

 white pine 



36% Subalpine fir 



7/11/01 



CURRENT COVERTYPE DISTRIBUTION 



Western white pine 9% 



Western larch/ 

 Douglas-fir 23% 



Mixed conifer 27% 



35% Subalpine fir 



1 % Douglas-fir 

 5% Lodgepole pine 



past timber harvesting. Suppressing 

 fires allowed these shade -tolerant 

 species to grow in the understory. 

 Past timber harvests changed 

 covertype distribution by 

 selectively removing some of the 



shade-intolerant western larch, 

 Douglas-fir, and western white pine 

 from the timber stands . 



In the analysis area, compared to 

 the Historic Data from the Flathead 

 Valley, Stillwater State Forest 

 ownership has approximately 25 

 percent less area in the seedling/ 

 sapling age class {O-to-39-year age 

 class) and 11 percent more area in 

 the old-stand age class. 



OhD-GROVrVH DISTRIBUTION 



For this analysis, old growth is 

 defined as stands that meet the 

 minimum criteria (number of trees 

 per acre that have a minimum 

 diameter at breast height (dbh) and 

 a minimum age) for a given site 

 {old-growth group from habitat 

 type) . These minimums can be found 

 in Green et al (Old Growth Forest 

 Types of the Northern Region) . The 

 SLI indicates that the estimated 

 timber stands that meet the old- 

 growth definition total 

 approximately 8,070 acres, or 12.3 

 percent of the analysis area. 



The 2 covertypes most represented in 

 old-growth stands in the analysis 

 area are western larch/Douglas -fir 

 (40 percent) and subalpine fir (26 

 percent) . 



INSECTS AND DISEASES/FOREST HEALTH 

 CONDITIONS 



The most prevalent insect- and 

 disease-related tree mortality 

 recently found on Stillwater State 

 Forest was attributed to the 

 Douglas-fir bark beetles and fir 

 engravers. The attacks by Douglas - 

 fir bark beetles have caused 

 mortality to individual and clumps 

 of Douglas -fir trees throughout the 

 analysis area. The attacks by fir 

 engravers have caused the death of a 

 relatively high number of grand fir 

 and subalpine fir in the lower 

 portion of the Swift Creek drainage 

 in the past year. 



The occurrence of root rot is fairly 

 common in the project area, but the 



Chapter Ill-Existing Environment and Environmental Consequences Page III-3 



