A total of 329 taxa of vascular plants in 52 families were 

 identified in the study area (Appendix B). Almost 9% (29 

 species) are adventive to this continent from Eurasia; many of 

 these are potentially serious weeds. Other species are 

 undoubtedly adventive to the area or to the sites they now 

 inhabit, but this is difficult to determine. 



The remainder of this section is devoted to summaries of 

 information on each of the seven proposed or prospective 

 sensitive and watch species in the study area. These summaries 

 provide information for identification and management for 

 conservation of the species, and include recommendations on 

 formal BLM status. Subheadings include description, present 

 legal or other formal status, geographic distribution, habitat, 

 population demography and biology, and management concerns. The 

 information is based on data collected from populations in this 

 study area as well as from other occurrences of the species in 

 Montana which are entered in the Biological Conservation Database 

 and on citations from literature. Throughout these summaries, 

 individual occurrences are referred to by the site name and last 

 three digits of the element occurrence code given on the EORs in 

 Appendix C. 



Astragalus scaphoides (Jones) Rydb. 

 Bitterroot Milkvetch 



A. DESCRIPTION 



General description: Astragalus scaphoides is a member of 

 an extremely diverse genus in the Fabaceae (Pea or Bean 

 Family). The plants are relatively large herbaceous 

 perennials with pinnately compound leaves borne on the 

 flowering stems. The inflorescence is a compact to somewhat 

 elongate raceme of many relatively large, zygomorphic 

 flowers. The perianth consists of a fused, five lobed calyx 

 and a cream to yellowish corolla which includes a banner 

 (the top segment), two wings (the side segments), and a keel 

 (the boat shaped bottom segment). There are 10 stamens, 

 nine connected in a group and one free, and a single ovary. 

 The mature fruit is a distinctively stalked legume which 

 contains several seeds. Photographic slides of the plant 

 are attached at the end of this report. 



Technical species description (guoted from Hitchcock and 

 Cronguist 1961): Sparsely strigillose perennial with a 

 taproot and branched crown; stems several, stout, ascending 

 to erect, 2-6 dm tall; leaves 10-25 cm long; stipules 

 lanceolate, 1-4 mm long, not connate; leaflets 15-21, lance 

 oblong to elliptic-oblong, 1.5-3.5 cm long, as much as 13 mm 

 broad, glabrous on the upper surface at least; peduncles 



