er aspen clones which suggests that these 

 clones expanded following treatment. Today, 

 understory vegetation and litter cover 54 to 

 90 percent of the ground and natural repro- 

 duction has largely stocked the forest. 



Twenty-eight specific vegetation types 

 were delineated in the original survey. These 

 have been broadly grouped into seven major 

 classifications (page 53). It should be recog- 

 nized that many variations in both species and 

 composition exist within these broad groups. 

 For example, the grass-forb type along the 

 ridge is quite different from that along the 

 stream bottom. Aspen, and the lush under- 

 story of grasses and forbs, covers more than 

 60 percent of both watersheds (table 3). Near 

 the ridgetops, aspen gives way to a sagebrush- 

 grass type and finally to a narrow band of 

 grasses and forbs near the -crests. A second 

 band of the grass-forb type generally follows 

 the stream bottoms of the two watersheds, 

 changing occasionally to a wet-meadow type. 

 Small areas of mountain brush (snowberry, 

 chokecherry, and serviceberry)' are scattered 

 throughout the watersheds, each of which has 

 one small area of conifers (Douglas-fir and 

 subalpine fir). 



^The common and scientific names of all species 

 identified on the watersheds are listed on pages 43 

 and 44. 



Timber stands on the study area have lit- 

 tle or no commercial value because of their 

 generally poor form and a lack of a suitable 

 market. 



Aspen 



The aspen type (fig. 7) occupies more than 

 60 percent of each of the two watersheds and 

 is found throughout except along the stream 

 bottoms and the ridgetops. The aspen general- 

 ly have poor form and show a fairly high in- 

 cidence of canker and heart rot, although 

 these characteristics vzxy considerably be- 

 tween clones. Average age of the aspen is 32 

 years although a few individual trees are in 

 the 70- to 80-year-old class. Average diameter 

 (d.b.h.) is 4.2 inches and the average height is 

 23 feet. Basal area varies from 20 to 140 

 square feet per acre and the average is 82. A 

 lush understory of forbs and grasses is charac- 

 teristic of these aspen stands. Some of the 

 more prevalent associated species are: Cali- 

 fornia brome; western wheatgrass, rye grass, 

 bluebell, sweetpea, and false hellebore. 



Grass-Forb 



The grass-forb type (fig. 8) occupies 12 to 

 13 percent of each of the two watersheds and 



Table 3. — Vegetation types of the Chicken Creek watersheds. A comparison of their extent on 

 each watershed and ground cover conditions on both watersheds 





Percent area 



Average ground cover on both watersheds 



Vegetation 



East 



West 











type 



Branch 



Branch 



Vegetation 



Litter 



Bare 



Rock 











Percent 







Aspen 



63.1 



66.0 



71.2 



18.7 



10.1 







Grass-forb 



11.6 



13.4 



51.4 



11.4 



24.6 



12.6 



Mountain brush 



7.0 



10.6 



64.1 



6.3 



23.3 



6.4 



Sagebrush 



15.1 



4.4 



49.4 



4.5 



19.1 



26.5 



Conifer 



2.4 



3.6 



48.5 



34.5 



16.5 



0.5 



Wet meadow 



0.8 



2.0 



82.0 



9.3 



8.2 



0.5 



11 



