17 



flowering; anthesis occurs in July, and the 

 plants are most conspicuous in the field at that 

 time. The taxon appears to have non-functional 

 anthers. Tetrazolium tests indicated 0-3'/. 

 production of viable seeds. Thus, Tr isetum 

 or thochaetum appears to be a sporadically 

 produced, virtually sterile hybrid. 



B. Demography. 



1. Known populations: Tr i setum or thochaetum is 

 known from eight populations, which are 

 herein grouped into three occurrences. 

 These populations are located along a 1.35 

 mile area on the southeast side of Granite 

 Creek, in association with four meadows 

 along the drainage. The total number of 

 stems observed was 66. 



S. General demographic details. 



a. Granite Creek South 



1. Area: Five populations, occurring 

 along edge of one meadow over cs. 

 10 acres. 



S. Number: 37 stems, all flowering; 

 occurs in clusters of 11, 5, S, ^ 

 and 15 stems, south to north. 



3. Density: Plants very scattered in 

 5 small clusters. 



^. Presence of dispersed seed: 

 Unknown, probably none. 



5. Evidence of reproduction: None. 



6. Evidence of population expansion 

 or decline: None. 



b. Granite Creek Central 



1. Area: Two populations, each on 

 edge of one of two meadows, over 

 ca. 12 acres. 



2. Number: SU stems, all flowering; 

 occurs in clusters of 13 (south 

 meadow) and 11 (north meadow) 

 stems . 



3. Density: Plants very scattered, 

 in two small isolated clusters. 



^. Presence of dispersed seed: 

 Unknown, probably none. 



5. Evidence of reproduction: None. 



6. Evidence of population expansion 

 or decline: None. 



c. Granite Creek North * 

 1. Area: One population, on edge of 



a single meadow, ca. 10 sq . ft. 



