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34 



sewn immediately, and given 70° days/35 

 nights, and 2.) seeds were sewn in flats 

 and given 35° temperatures for 30, 45, and 

 60 days; after each time interval, 

 portions of the seed were removed from 

 cold treatment and germination attempts 

 made. None of these treatments resulted 

 in germination. It was thought that this 

 may have been due to the drought year in 

 1988; additional attempts are currently 

 being made using seed collected in 1989 

 (P. Burke, pers. comm.). 



5. Seedling ecology: Details unknown. Ramstetter 

 (1983) felt that because seed dispersal occurs 

 so late in the growing season, germination 

 probably occurs in the spring; the apparent 

 requirement for a cold treatment upholds this 

 hypothesis. In the three monitoring transects 

 established in 1989, very few seedlings were 

 observed (a total of 17 in 100 lm 2 plots) . 

 Those observed were very small, and it is 

 possible that others within the transects were 

 missed during the studies. Also, numerous 

 seedlings may perish or become dormant earlier 

 in the growing season, as the habitats become 

 drier; such a dormancy pattern has been 

 observed for seedlings of Silene spaldinqii . a 

 rare perennial plant species occurring in 

 northwestern Montana. Seedlings of the latter 

 become dormant during the summer months under 

 greenhouse conditions (Lesica 1988) . 



6. Survival and mortality: No quantitative 

 information; future readings of the monitoring 

 transects will provide detailed data. See 

 Section I.7.B.2., p. 26, for a discussion of 

 observed fluctuations in some population sizes. 



7. Overall assessment of t axon's reproductive 

 success: Although details on rates of seed 

 germination and seedling establishment are 

 largely unknown, these appear fairly low in P. 

 lemhiensis . especially considering the relative 

 abundance of observed seed production. Also, 

 the small average population size suggests that 

 reproductive success is fairly low. Additional 

 studies on the ecology of seed germination and 

 establishment are needed. 



