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I 



33 



irregular in shape, and up to 2 mm in 

 size. It is likely that most seeds simply 

 fall directly to the ground from the 

 dehisced capsules. 



b. Specific agents: None known or apparent. 



c. Vulnerability of dispersal agents and 

 mechanisms: Not applicable. 



d. Patterns of propagule dispersal: Details 

 unknown. In demographic monitoring 

 transects established in 1989, some 

 seedlings were observed; these were always 

 in the vicinity of mature reproductive, 

 and presumably parental, plants (Shelly 

 1990b) . 



4. Seed biology. 



a. Amount and variation of seed production: 

 Seed production in three monitoring 

 transects varied only slightly, from 32.7 

 to 36.0 seeds per fruit; the average 

 number of fruits per fruiting plant ranged 

 from 12.1 to 19.2 (Shelly 1990b). 

 Continuing measurements from these 

 transects will provide information 

 regarding variation in annual seed 

 production. 



b. Seed viability and longevity: Unknown. 



c. Dormancy requirements: Unknown. 



d. Germination requirements: In laboratory 

 seed germination experiments, only seeds 

 that were cold-treated or treated with 

 gibberellic acid (a growth hormone) 

 germinated; it is likely that seeds of P. 

 lemhiensis require a cold treatment prior 

 to germination in the field (Ramstetter 

 1983) . 



e. Percent germination: In both the cold and 

 gibberellic acid treatments, only about 4% 

 of the seeds germinated after 

 approximately two weeks; most seeds did 

 not germinate at all (Ramstetter 1983) . 

 Germination trials have also been 

 conducted by Bitterroot Native Growers 

 (Corvallis, Montana) . The following 

 treatments were performed: 1.) seeds were 



