34 



Erigeron linearis (Hook.) Piper 



LINEARLEAF FLEABANE 



Aster Family (Asteraceae) 



CONSERVATION STATUS 



U. S. Fish and Wildlife Ser\'ice: None. 



Bureau of Land Management: This species was not previously known from lands 

 administered by the Bureau of Land Management, so it has not been reviewed for ELM 

 status. It is not recommended for ELM designation at this time because of the questions 

 raised about the naturalness of the study area population. 



Montana Natural Heritage Program rank: G5 SI. 



DESCRIPTION: Linearleaf fleabane has unbranched stems, 5-30 cm (2-6 in) tall, from a stout 

 taproot and branched rootcrown. The mostly basal leaves are linear and 1-9 cm (0.5-3.5 in) long; 

 the bases of the stems and leaves are enlarged and straw-colored or purplish, and the herbage is 

 covered with fine gray hairs. The flower heads are usually solitary at the ends of the stems; the 

 involucral bracts are 4-7 mm long and are covered with long, appressed hairs and occasionally 

 also with glads. The 15-45 yellow rays are 4-1 1 mm long. The yellow disk flow^ers are 3-5 rmn 

 long (Figure 14; Appendix D-9). There are 10-20 pappus bristles at the top of each seed (achene). 

 Plants were near peak flowering at 14 June 1995. 



This is the only yellow-flowered fleabane in Montana. The Erigeron genus is distinguished from 

 other yellow-flowered genera in the Aster Family with which it might be mistaken in having 

 involucral bracts that are in only one series. 



GEOGRAPHICAL DISTRIBUTION 



Global distribution: Southern British Columbia, south through eastern Washington and 

 Oregon to northern Nevada and Yosemite National Park, east through central Idaho to 

 Yellowstone National Park and southwestern Montana. 



Montana distribution: The three collections include one in the Eitterroot Valley made 

 on private lands in 1973, one historic collection west of Dillon, and the recent study area 

 collection which may correspond to the vague location information of the historic 

 collection (Figure 15). 



Grasshopper distribution: The single study area collection was confined to a small 

 discrete area. It may be a part of the native flora elsewhere in the local landscape, or an 

 accidental introduction that was brought in with mining activity (Figure 15). 



