livestock. A large part of the damage appears to be due to 

 stem-girdling insects. Both beetles (Order Coleoptera, 

 Families Buprestidae and Cerambycidae) and sawflies (Order 

 Hymenoptera, Family Cephidae) are known to exhibit 

 stem-girdling behavior. Conclusive evidence linking any 

 particular herbivore to the destruction of the inflorescences 

 of A. scaphoides is not currently available. In addition to 

 the inflorescence destruction, leaf damage was observed on many 

 A. scaphoides plants. This damage appears to be caused by 

 biting and chewing insects (probably Orders Orthoptera and 

 Lepidoptera) (see Lesica in review). 



2. Competition 



a. Intraspecific— Unknown. 



b. Interspecific—Species does not seem to suffer any adverse 

 effects in dense stands of sagebrush. Competition with 

 grasses and forbs may occur. 



3. Toxic and allelopathic interactions — None known. 

 Hybridization 



1. Naturally occuring--At a number of the sites in Idaho A. 

 scaphoides co-occurs with A. atropubescens . These two species 

 are closely related and are very similar vegetatively. No 

 obvious hybrids were observed. 



2. Artificially induced—Unknown. 



3. Potential in cultivation— Unknown. 



Other factors of population ecology — None known. 



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