44 



CONSERVATION STATUS 



Lomatiiim attenuatum Evert 



TAPERTIP BISCUITROOT 



Parsley Family (Apiaceae) 



U.S. Fish and Wildlife Sen-ice: 3C (USDI Fish and Wildlife Service 1993); This 

 signifies that the species has "proven to be more abundant or widespread than previously 

 believed and/or.. ..(is) not subject to any identifiable tlireat." 



Bureau of Land Management: Lomatium attenuatum is included on the BLM's list of 

 proposed sensitive species for Montana (USDI Bureau of Land Management 1993). 



Montana Natural Heritage Program rank: G2 SI; in Wyoming, the species has 

 recently been reranked as S2 from S3 (Fertig 1996), and its global rank changed from G3 

 to S2 accordingly. 



DESCRIPTION: Taper-tip biscuitroot is a perennial herb with 1 to several stems, 10-25 cm (4- 

 10 in.) high, from a long, thick taproot and a simple or branched rootcrowTi. The few alternate, 

 elliptic leaves are 3-times divided into narrow ultimate segments, 2-5 mm long and less than 2 m 

 wide. The leaf petioles form a dilated sheath that enfolds the stem. Foliage is mildly sandpaper- 

 like but without hair. Tiny yellow flowers are borne in hemispherical clusters, subtended by 0-6 

 separate, linear bracts (involucel), that are arranged at the ends of 5-8 stalks, 3-5 mm long, in an 

 umbrella-like inflorescence at the top of the stem. Five separate petals, 1-2 mm long, sunnount 

 an ovary that matures into a glossy, glabrous, flattened elliptical fruit 5-8 mm long, with four low 

 ridges on each face (from Evert 1983; Figure 18; Appendix D-14). The flowers appear with the 

 leaves by early May. Individual plants ha\e a range in maturity between umbellets on a plant so 

 that flowering and fruiting is staggered and extended for several weeks in favorable years. 

 Flowering continued into early June in 1995. 



Lomatium is a difficult genus; a hand lens or microscope and technical key are essential for 

 determination. This species is most similar to L. cous, which it resembles in habit and leaf 

 dissection. The latter has an involucel of elliptic bracts and is less scabrous. 



GEOGRAPHIC DISTRIBUTION 



1. Global distribution: The species is known only from Park County in northwestern 



Wyoming (Evert 1983, Dom 1992) and fi-om southwestern Beaverhead County, Montana. 



2. Montana distribution: Lomatium attemmtum was first discovered in the state in 1993 by 



Peter Lesica on BLM land in the Tendoy Mountains (Vanderhorst and Lesica 1 994). 

 Additional populations were found in 1 994 in the Tendoy Mts. and to the north near 



