Site Basic Record 

 CENTENNIAL SANDHILLS 



From Monida, proceed east on main Centennial Valley gravel road ca. 10 miles to a dirt road 

 leading north. Take this road 3 miles to a T intersection. Stay on the most prominent road 

 leading east and continue for 16.5 miles to a Y intersection. The site extends east from this 

 point ca. U mi les. 



The site is characterized by sandhills of glacially-derived alluvial sands up to 50 feet tall 

 in various stages of stabilization by vegetation. The most stable surfaces feature Artemisia 

 tripartita and A. tridentata/Festuca idahoensis communities, while Agropyron 

 dasystachum/Phacel ia hastata communities occur in blowout areas and more active dune surfaces. 

 Five state rare plant speces are known to occur on the site. 



COUNTY: Beaverhead 



USGS QUADRANGLE: LOUER RED ROC< LA<E 



TOWNSHIP-RANGE: 013S002U SECTION: 23 



QUARTER/ADDITIONAL SECTIONS: Portions of 10,11,13,14,22,24,26,27 



BOUNDING RECTANGLE: S: 444035N N: 444245N E: 1114510W W: 1115045U 



BOUNDARY JUSTIFICATION: The site encompasses the sand dune complex, including rare plant populations and 

 a spring north of the dune area, which may be one source of groundwater for 

 sandhills and plant populations. 



APPROXIMATE ACREAGE: 4000.00 



GENERAL RATING: 2 



A and B-ranked element occurrences. 



BIODIVERSITY SIGNIFICANCE: B2 



Five rare plants are associated with the sandhills and blowouts, including Astragalus ceramicus 

 var. apus (G4T3S1), Cryptantha fendleri (G4S1), Elymus flavescens {G4S1), Eriogonum ovalifolium 

 var. nevadense (G5T4S1), and Oenothera pallida var. idahoensis (G5T3QS1). A rare plant 

 community, Agropyron dasystachyum/Phacel ia hastata {G2?S2?) is present. Ferruginous hawks nest 

 on the top of sand dunes, and badger, red fox, and coyotes maintain dens in the dune complex. 

 Other species that use the area include: sandhill crane, snowshoe hare, antelope, mule deer, 

 elk, and moose. 



OTHER VALUES: VI 



One of only two sandhill complexes in Montana. 



PROTECTION URGENCY: P3 



Potential threats from oil and gas development. Cattle grazing on portions of the site may 

 degrade vegetation quality significantly. ACEC designation and withdrawal from grazing for at 

 least the east half of section 22 may be desirable. 



MANAGEMENT URGENCY: M3 



Maintain dynamic nature of dunes. Carefully manage cattle use to minimize impacts. 



CONSERVATION INTENT: Recommend establishment of a BLM ACEC. 



PROTECTION COMMENTS: 



LAND USE: Section 22, the U2 of 23, and N4 of 27 have received light grazing from 1977 to 1981, and 



little or no grazing each year from 1982 to 1987. the E2 of section 23, all of section 24, and 

 the W3 of section 19 are privately-owned and have been continuously grazed from 1977-1987. 

 There is also a cattle trough on the private land that concentrates cattle in a small area for 

 long periods. Grazing is effective in maintaining blowouts in the early successional stages 

 most conducive to the maintenance of rare plant populations. 



NATURAL HAZARDS: None known. 



EXOTICS: This is a very pristine site, with very few introduced species. Bromus tectorum is present but 

 not in abundance. 



