5. OTHER NEGATIVE INTERACTIONS: Cattle occur at 

 nearly all A^ fecunda sites. Although they 

 probably do not graze the plants, they may have 

 adverse effect in some areas by destroying 

 established plants or the soil crust that supports 

 them (Lesica and Shelly 1992) . Exclosure studies 

 at two sites near the Big Hole River suggest that 

 grazing may sometimes have detrimental effects 

 (Lesica 1993). At one site A^ fecunda increased 

 in the grazing exclosure, while at the other it 

 decreased relative to controls. Livestock are 

 important vectors for exotic weed infestations. 



6. HYBRIDIZATION: Arabis fecunda is a distinctive 

 member of the genus in Montana (Rollins 1984) . 

 Although A_^ holboellii does occur at some sites, 

 there is no evidence of hybridization. 



LAND OWNERSHIP 



1. U.S. NATIONAL FORESTS 



a. BEAVERHEAD NATIONAL FOREST: Six sites in the 

 East Pioneer Range in Beaverhead and Silver 

 Bow counties are entirely or partially on 

 lands administered by Beaverhead N.F. A list 

 of sites and ownership are given in Table 5. 



b. DEERLODGE NATIONAL FOREST: Three sites in 

 the Highland Mountains in Silver Bow County 

 are entirely or partially on land 

 administered by Deerlodge N.F. A list of 

 sites and ownership are given in Table 5. 



2. U.S. BUREAU OF LAND MANAGEMENT: Six sites in the 

 East Pioneer and Highland ranges in Beaverhead and 

 Silver Bow counties are on land administered by 

 BLM's Butte District. Two of the sites are in the 

 Humbug Spires proposed wilderness area. A list of 

 sites and ownership are given in Table 5. 



3. STATE OF MONTANA: Four sites in the Sapphire, 

 East Pioneer and Highland ranges in Ravalli, 

 Beaverhead and Deer Lodge counties are partially 

 on state lands. A list of sites and ownership are 

 given in Table 5. 



4. PRIVATE: Six sites in the Sapphire, East Pioneer 

 and Highland ranges in Ravalli, Beaverhead and 

 Deer Lodge counties are partially on deeded land. 

 A list of sites and ownership are given in Table 

 5. 



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