Bromus tectorum 



Capsella bursa-pastoris 



Carex geyeri 



Chaenactis douglasii 



Chrysopsis villosa 



Cryptantha celosloides 



Danthonia unispicata 



Erioqonum ovalifolium 



Gayophytum decipiens 



Lesquerella klausii 



Lomatium dissectum 



Lomatium triternatum 



Mentzelia dispersa 



Oryzopsis hymenoides 



Penstemon attenuatus 



Phacelia hispida 



Polygonum douglasii ssp. douglasii 



Prunus virginiana 



Purshia tridentata 



Ribes cereum 



Symphoricarpos albus 



TOPOGRAPHY: Polygonum douglasii ssp. austinae 

 occurs on flats to steep slopes at elevations 

 ranging from 4320-6600 feet. On the Helena 

 National Forest, the plant is found on east, 

 south, or west-facing slopes of 5-45%. It is 

 typically restricted to an upper portion of the 

 exposed slope, though also found in an unvegetated 

 channel bottom that cut through the outcrop at one 

 site. Elevation at these sites ranges from 4320- 

 6220 feet. 



SOIL RELATIONSHIPS: In Montana Polygonum douglasii 

 ssp. austinae grows in silty soils derived from 

 shale parent material, or at less weathered sites, 

 in the shale itself. This is particularly true of 

 these sites in the Helena National Forest. 



REGIONAL CLIMATE: The climate of west-central 

 Montana can generally be classified as cool, dry, 

 and continental, with locally greater amounts of 

 precipitation in the mountains. In the Helena 

 National Forest the northern populations of 

 Polygonum douglasii ssp. austinae are 15-20 miles 

 southeast of the closest weather station, Holter 

 Dam. However these populations occur at 4320-6220 

 feet elevation as compared to the weather station 

 at 3487 feet. The southern populations are 12-15 

 miles east-southeast of the closest weather 

 station at Townsend. These populations occur at 

 4920-6220 feet elevation as compared to Townsend 



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