24 



rodents. The mericarps do have oil tubes (Evert and 

 Constance 1982), and the oil in the fruit may serve as 

 an attractant to animal dispersers (van der Pijl 1982), 



b. Specific agents: None known. 



c. 



Vulnerability of dispersal agents and mechanisms: 

 Unknown. 



d. Patterns of propagule dispersal: Unknown. 

 It. Seed biology. 



a. Amount and variation of seed production: Details are 

 unknown. Most plants that were observed produced some 

 fruit, and most inflorescences examined had at least 

 one maturing fruit. 



b. Seed viability and longevity: Unknown. 



c. Dormancy requirements: Unknown. 



d. Germination requirements: Unknown. 



e. Percent germination: Unknown. 



5. Seedling ecology: Details are unknown. Many species of 

 windswept alpine fellfields require the ameliorated 

 microclimate, and accumulations of organic matter, provided 

 by "nurse plants" (Griggs 1956). Shoshonea pulvinata may 

 have similar requirements. 



6. Survival and mortality: Details are unknown. Shoshonea 

 will tolerate only partial shading, and occurs mainly in 

 relatively open plant communities. These factors suggest 

 that it is a stress tolerator species sensu Grime (1979), 

 and is thus probably a poor competitor. 



7. Overall assessment of taxon's reproductive success: The 

 presence of small non-reproductive plants, which are 

 presumed to be juveniles, in all of the Montana Shoshonea 

 pulvinata populations indicates that the species is 

 reproducing successfully. The fact that no seedlings were 

 observed during the 1986 and 1987 field seasons may be a 

 result of the general drought conditions which have 

 prevailed during that time. Judging from the large size of 

 many of the plants, Shoshonea is a long-lived perennial. 

 The relatively long life of individual plants probably 

 compensates for sporadic seedling recruitment. There is 

 unoccupied, apparently suitable habitat in both the Pryor 

 and Beartooth mountains in Montana, perhaps indicating that 

 Shoshonea does not readily establish new populations. 

 Nevertheless, it appears that established populations are 

 stable at this time. 



