b. Seed viability and longevity—Unknown. 



c. Dormancy— Unknown. 



d. Germination requirements—Unknown. 



e. Percent germination— Unknown. 



5. Seedling Ecology— Only a small number of seedlings were 

 observed during field work. Their ecology is unknown. 



6. Survival and mortal ity— Unknown. 



7. Overall assessment of reproduction success— Reproductive 

 success is minimal in most populations due to herbivory and 

 flower/furit abertion (see section on negative interactions). 

 Reproduction may be inadequate to maintain some populations. 



Population Ecology 



A. General summary— Astragalus scaphoides is a member of stable, 

 climax, shrubland communities. It is apparently able to compete 

 successfully with the vegetation of these communities. There is 

 evidence that herbivores, both insect and mammalian, are severely 

 restricting the reproductive ability of this species. 



B. Positive and neutral interactions— Astragalus scaphoides is, in all 

 likelihood, mycorrhizal with an endophytic fungi in the Family 

 Endogonaceae. A. scaphoides may also have nitrogen-fixing nodules 

 - a symbiotic relationship with bacteria of the genus Rhizobium . 



C. Negative interactions 



1. Herbivores, predators, pests, parasites and diseases— In the 

 five populations of A. scaphoides studied 45-39i of the 

 reproductive individuals had their inflorescence destroyed in 

 the flowering stage. Part of this damage is thought to be 

 caused by mammalian herbivores such as deer, antelope, or 



10 



