plants, six had between 501-1000 plants, four had over 

 1000 individuals. Thus the majority of the populations 

 are quite small, with approximately 55 percent of the 

 populations containing under 100 plants, and 

 approximately 78 percent containing fewer then 500 

 plants. The final 10 populations have no accurate 

 population counts (Table 1) . All populations occur in 

 Missoula and Powell counties, Montana. 



I.7.B.2. General demographic details: The 1990 survey assessed 

 population survivorship characters: seed dispersal and 

 establishment (= number of basal rosettes) and 

 reproduction (= number of flowering or fruiting plants) 

 Data collected for the 27 populations are in Table 2, 

 pp. 9-14. 



I.7.D.6. Survival and mortality: Better then half (15) of the 

 27 populations surveyed in 1990 declined from the 1986 

 or 1988 population levels (Table 1) . Two populations 

 contained approximately the same number of individuals 

 as the 1986 counts, and 10 populations increased in 

 size. Of the twelve populations with greater than 25 

 plants, there was a nearly even split between immature 

 (rosette stage) and adult plants (flowering stage) 

 (Table 2). Thus, at least in these populations, 

 reproduction and seedling establishment appears to be 

 high. However, road maintenance and use, herbicide 

 applications, and cattle grazing affected the roadside 

 habitat of G. howellii and reduced plant reproduction 

 and survival in the other 13 populations (Table 2) , 



I.lO.A.l. Review of past management and land-use experiences: 



The Cottonwood Creek population (040) on the Blackfoot- 

 Clearwater Wildlife Management area underwent a 

 substantial decline. This population was rated as the 

 "best" G. howellii population in Montana during the 

 1986 survey. In 1990, only four basal rosettes were 

 located during the survey. The occurrence of dead 

 spotted knapweed ( Centaurea maculosa ) plants, the 

 absence of spotted knapweed basal rosettes or other 

 broadleaf plants, and the presence of dead shrubs in a 

 20 foot strip along the fence suggest that a persistent 

 herbicide was used on the area. Cattle grazing in the 

 fenced area may have created additional stress on the 

 G. howellii population. Mike Thompson, Montana Fish, 

 Wildlife, and Parks Dept., confirmed that Tordon was 

 used in spot treatments during fall 1989 on this 

 pasture. He was unaware of the G. howellii population 

 in the pasture. 



