scientific Name: ARTEMISIA TRIDENTATA/AGROPYRON SPICATUM PA 

 Common Name: BIG SAGEBUSH/BLUEBUNCH WHEATGRASS ASSOCIATION 



Global rank: G5 Forest Service status: 

 State rank: S5 Federal Status: 



Element occurrence code: C3A2BCACA0 . 019 



Survey site name: BLOCK MOUNTAIN - CENTER 



EO rank: AB 

 EO rank comments: PRISTINE EXAMPLE OF A COMMON COMMUNITY. 



County: MADISON 



USGS quadrangle: BLOCK MOUNTAIN 



Township: 004S Range: 008W Section: 23 Precision: S 



Township-range comments: SE4,26NE4NE4 



Survey date: 1991-06-03 Elevation: 5990 

 First observation: 1991 Slope/aspect: 0% / NORTH 



Last observation: 1991-06-03 Size (acres) : 5 



Location: 



FROM GLEN, PROCEED SOUTH ON PAVEMENT CA. 0.7 5 MILE TO THE BURMA ROAD. 

 TAKE THIS ROAD 7.5 MILES TO SANDY HOLLOW. BLOCK MOUNTAIN IS 1.5 MILES 

 NORTHEAST. PLOT IS LOCATED ON BROAD, FLAT SUMMIT RIDGE, 0.15 MILE 

 SOUTH OF THE HIGHEST SUMMIT OF BLOCK MOUNTAIN. 



Element occurrence data: 



WITHIN PLOT, 18 SPECIES OBSERVED. DOMINANTS INCLUDE: ARTEMISIA 

 TRIDENTATA (30% CANOPY COVER), ARTEMISIA FRIGIDA (10%), AGROPYRON 

 SPICATUM (20%), BOUTELOUA GRACILIS (5%), AND ORYZOPSIS HYMENOIDES 

 (3%) . COMPLETE LIST ON FILE AT MONTANA NATURAL HERITAGE PROGRAM. 



General site description: 



STRUCTURALLY CONTROLLED MOUNTAIN SLOPE; PLOT POSITION IS WIDE RIDGE 

 SUMMIT. BASALT PARENT MATERIAL AND BOROLLIC LITHIC CALCIORTHID SOIL 

 SUBGROUP. GROUND COVER: BARE SOIL (10%), TOTAL COARSE FRAGMENTS (40%). 



Land owner/manager: 



PRIVATELY OWNED LAND (INDIVIDUAL OR CORPORATE) 

 BLM: BUTTE DISTRICT, DILLON RESOURCE AREA 



Comments: 



MTNHP PLOT #91RD003. SURVEY CONDUCTED BY R. L. DEVELICE, P. ACHUFF AND 

 A. McALPINE. ADDITIONAL PLOTS OF THIS COMMUNITY TYPE WERE SAMPLED AT 

 THE SITE, INCLUDING PLOT #91RD005, LOCATED CA . 0.3 MILE NORTH, AND 

 PLOT #91RD002, LOCATED CA. 0.12 MILE SOUTHWEST. 



Information source: 



DEVELICE, ROBERT. [COMMUNITY ECOLOGIST] . MONTANA NATURAL HERITAGE 

 PROGRAM, 1515 EAST 6TH AVE., HELENA, MT 59620. 



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