(potential natural vegetion based associations) are yet 

 to be documented. The area capable of supporting the 

 subalpine fir / western meadowrue forest (Abies 

 lasiocarpa I Thalictrum occidentak Forest; 

 ABILAS/THAOCC) ranges from the steep, north- 

 facing slopes at the lowest elevations of the RNA to the 

 upper slopes (7,900 ft. plus) where it extends to warmer 

 slopes as increasing elevation with colder temperatures 

 and increased precipitation compensate for aspect with 

 increased solar insolation load. The ground surface is 

 continuously carpeted with litter, having virtually no 

 stone or gravel exposed. This plant community could 

 be "typed" in two ways, using Pfister et al. 1977 (which 

 is specific to Montana) and Steele et al. 1983 (which is 

 specific to eastern Idaho and western Wyoming) ; the 

 undergrowth and associated mesic environment better 

 correspond to the ABILAS / THAOCC climax 

 association described in Steele et al. (1983) as a minor 

 type in northwestern Wyoming. 



Most of the stands are rather open (verging on 

 woodland at less than 70% canopy cover) , not 

 exceeding 65 to 75 ft. in height, single-aged to two- 

 aged and dominated by Pseudotsuga in the upper 

 canopy. At least two old-growth stands were 

 encountered, where Pseudotsuga exceeding 20 inches 

 and 200 years were common. Though there are 

 occasional mature Abies specimens in the upper 

 canopy, P. engelmanrdi is the more common 

 representative of mature to late serai tree species. At 

 the start of reconnaissance from the slope bottom, it 

 was especially notable that virtually all smaller Abies 

 projecting above the snowline had been browsed, 

 ostensibly by moose. Given that most of these Abies 

 stems were decidedly shorter than they should have 

 been given the thickness of their stems, it is inferred 

 that this snowline browsing has continued for years and 

 is the primary reason these stands will never become 

 Abies dominated. Serai Pinus flexilis is perhaps the most 

 abundant canopy tree after Pseudotsuga and Picea. 



Undergrowth cover, which varies inversely with the 

 degree of canopy shading, ranges from just barely more 

 than trace amounts to 50% plus and is dominated by 

 forbs; those with the greatest cover and constancy 

 include showy aster (Aster conspicuus), western 

 meadowrue (Thaliarum occidentale) , mountain sweet- 

 cicely (Osmorhiza chileTisis), heart -leaved arnica (Arnica 

 cordifoUa), northern valerian (Valeriana dioica) and 

 slender cinquefoil (Poteruilla gracilis). Shrub cover 

 barely exceeds trace amounts; various Ribes species 

 (currant or gooseberry) and mountain snowberry 

 (Symphoricarpos oreophilus) are regularly present. The 

 grass component is also depauperate with nodding 



bluegrass (Poa reflexa) and pinegrass (Calamagrostis 

 rubescens) usually the only species present and always 

 with low cover, usually not exceeding 5%. [Plots 

 NHMTECRN98SC0033, NHMTECRN98SC00351 



Abies lasiocarpa /Juniperus communis Woodland 



[ABILAS /JUNCOM) 



subalpine fir / common jumper woodland 



This is a very common plant association, identified 

 from the drier mountain ranges of eastern Oregon and 

 Washington, eastward into Montana and Wyoming 

 and south as far as New Mexico and Arizona (see 

 explanation under ABILAS / THAOCC association as 

 to why these stands dominated by Douglas-fir 

 (Pseudotsuga menziesU) are named for subalpine fir 

 (Abies lasiocarpa) . Common juniper Quniperus 

 communis) is a relatively stress-tolerant shrub. Within 

 the context of this relatively mesic, generally north- 

 facing flank of the Centennial Range it represents 

 habitats experiencing greater moisture stress than are 

 reflected by the presence of other forested associations 

 commonly encountered that instead have subalpine fir 

 (Abies lasiocarpa) in association with either western 

 meadowrue (Thalictrum occidentale), pinegrass 

 (Calamagrostis rubescens) or with shiny-leaf spireaea 

 (Spiraea betulifoUa). On the RNA, ABILAS / 

 JUNCOM was encountered on warmer exposures, 

 those with a westerly component, and above 7,800 ft., 

 though it is capable of occurring at much lower 

 elevations. It generally grades to ABILAS / mountain 

 gooseberry (Ribes montigenum) , which is present on the 

 RNA as narrow patches where snowpacks are deeper 

 than on surrounding terrain. 



Being a woodland, tree canopy cover is generally below 

 60% and tree form approaches "stunted" with heights 

 barely exceeding 40 feet at more than 350 years of age. 

 Engelmann spruce (Picea engelmannii) and Abies 

 lasiocarpa are present mostly in the sapling/seedling 

 layer, though scattered mature and old-growth Picea 

 engelrruinnii are typically present as well. This 

 association is at the dry extreme of Abies lasiocarpa 

 distribution and this species probably will never achieve 

 canopy dominance. The canopy dominant over most of 

 the stand is Pseudotsuga, though limber pine (Pinus 

 flexilis) is a major component in patches. Common 

 juniper (juniperus communis) dominates the 

 undergrowth, its cover generally exceeding 10%. The 

 graminoid element is especially depauperate with only 

 traces of nodding bluegrass (Poa reflexa) and Ross sedge 

 (Carex rossiil) . Showy aster (Aster conspicuus) is the forb 

 with highest cover in the plot and it and lanceleaved 



54 



