Dalea villosa (Nuttall) Sprengel 



SILKY PRAIRIE CLOVER 



Bean Family (Fabaceae) 



CONSERVATION STATUS 



U. S. Fish and Wildlife Service: none 



Bureau of Land Management: Watch (USDI BLM 1996). 



Montana natural Heritage Program: G5 SI; demonstrably secure globally, but may be 

 critically imperiled in Montana where it is extremely rare. 



DESCRIPTION: Silky prairie clover is a perennial herb with ascending, branched stems, 20-35 

 (50) cm (8-14 in) high, arising from red-orange roots and rootcrown. The alternate, pinnately 

 compound leaves are 2-4 cm (ca. 1 in) long and have 11-21 linear leaflets. Foliage has numerous 

 sunken glands and is densely long and hairy. Pink to rose-purple flowers are densely crowded in 

 cylindrical spikes, 3-12 cm (1-5 in) long, at the ends of stems and branches. Each flower is 4-6 mm 

 long and has 4 separate petals, a densely spreading-hairy, 5-lobed, cup-shaped calyx, and 5 stamens 

 that are usually longer than the petals. The narrowly egg-shaped pods are 2-3 mm long and densely 

 long-hairy. Flowering in July-August. 



Other Dalea species in Montana usually have 1 1 or more leaflets, and are not as conspicuously hairy. 

 Its flowers form an elongate spike and its stems are more highly-branched than other species in the 

 genus; it may superficially resemble a shrub in its growth form. The combination of long-hairy calyx 

 and 5 stamens further separate this from other species of Dalea and species of scurfpea (Psoralea) 

 and leadplant (Amorpha). 



GEOGRAPHICAL DISTRIBUTION 



Global distribution: Midwest and Great Plains, 

 from western Wisconsin and southern Manitoba 

 to southern Saskatchewan and eastern Montana, 

 south to Oklahoma, Texas and Colorado (Great 

 Plains Flora Association 1986). 



Montana distribution: Carter County. 



Carter County distribution: Prior to 1997, one 

 population was known from the state at Medicine 

 Rocks State Park. Another population was found 

 in 1997 adjoining and possibly extending onto 

 BLM land in the vicinity of the Humbolt Hills in 

 northeastern Carter County. 



silky Prairie Clover 



vQ 



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