Pseitdotsuga menziesii/Festuca idahoensis plant association 



(PSEMEN/FESIDA; Douglas-fir/Idaho fescue; MTNHP rank G5/S4; 1 plot) 



Environment: PSEMEN/FESIDA, one of three study area woodland plant associations, was 

 sampled once in the southwestern part of the study area on a moderate upper slope with west 

 aspect at 7,900 feet. Nearby dryer aspects have Artemisia tridentata ssp. vasyana communities. 



Soils: The plot is within the Shadow complex soil mapping unit (USD A Soil Conservation 

 Service 1989). These are deep, somewhat excessively drained stony, chaimery, and sandy loams, 

 which are locally derived from gneiss basement rock. The ground surface of the plot is mostly 

 covered by litter, and the little exposed substrate is mostly soil. 



Vegetation: The sampled stand had a typical woodland structure with a relatively open canopy 

 (ca. 50% cover) dominated by short-stature, multi-aged Pseudotsuga menziesii. Pole-sized Pinus 

 flexilis is well represented. Slirub cover is limited to a trace of Artemisia tridentata var. vasyana. 

 Cover by grass is about 20%, dominated by Festiica idahoensis and Poa secunda. Forb cover is 

 also around 20%, dominated hy Astragalus miser. There is a trace of bryophyte cover. 



Comments: The sampled plot is nearby an area recently opened to logging and may represent the 

 community type of some of the cutting units. Timber productivity of the type is low (Pfister et al. 

 1977), and may be especially low in the Ruby Range as the low canopy cover in the plot is 

 indicative of droughty conditions for the type. 



Pseudotsuga menziesii/scree community type 



(PSEMEN/scree; Douglas-fir/scree; MTNHP G5/S4; 1 plot) 



Environment: In the Ruby Range PSEMEN/scree occupies steep, dry, warm, south and 

 southwest facing canyon slopes with unstable limestone scree substrate. Where it was sampled in 

 Laurin Canyon it is above a bench with a big sagebrush community {Artemisia tridentata ssp. 

 Uidentata/Agropyron smithii). Cooler aspects on the slopes across the canyon ai-e mostly 

 Pseudotsuga menziesii/Arnica cordifolia communities. 



Soils: The plot is located within the Whitecow-rock outcrop complex soil mapping unit (USDA 

 Soil Consers'ation Service 1989). The Whitecow series is a deep, well drained Cryoclirept formed 

 in limestone colluvium. PSEMEN/scree occupies the scree slopes witliin the complex. Scree 

 substrates are unstable, with high content of coai'se rock fragments and little horizon 

 development. 



Vegetation: The plot in the study area has widely spaced Pseudotsuga menziesii, Juniperus 

 scopulorum, and Pinus flexilis with depauperate shrub and forb understories. Typically 

 Pseudotsuga menziesii develops into large old growth trees on scree slopes (Cooper et al. 1995), 

 but much of this community type in the study area has been logged for fuelwood. Cercocarpus 

 ledifolius is the only well represented shrub in the plot. There is a trace of the bunchgrasses 

 Agi'opyron spicatum (syn. Elymus spicatus, Pseudoregneria spicatum) and Oryzopsis 

 hymenoides. The most common forb is Senecio canus while scattered Cirsium subniveum, 



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