DISCUSSION 



Interpretation of results is conditioned by all of the challenging new questions surrounding 

 rare species and their habitats on the Ashland District. Foremost among these questions is the 

 heretofore unrecognized need for making distinctions between Astragalus harhi and A. 

 hyalUms, as the latter has now been documented from the District. Tliree previously - 

 identified^, barhi population sites and four potential ntw A. barrii sites that were found only 

 in vegetative condition need to be revisited and examined during the flowering times of both 

 species in order to make positive identifications. 



The study results provide evidence to support nomination of Carex gravida as sensitive, in 

 addition to naming two species known only from historical collections in the District 

 {Amorpha canescens and Ceanothus herbaceus) as watch. Two more species that are 

 represented by historical collections among the YCC set of important range plants are 

 recommended for designation after the specimens are verified: Cypripedium calceolus var. 

 parviflorum is already designated as sensitive, and Mentzelia nuda, not previously 

 documented on Montana units of the Custer National Forest, is appropriate for designation as 

 watch. The failure to turn up these two species and many others among the YCC collection 

 that were considered important range plants during the 1930s calls for further investigation. 



Two new additions to the state flora were documented (Heidel in progress), one of which has 

 provisionally been added to the state list (Evax prolifera), and the other of which is locally 

 widespread and under no immediate tlireats (Ipomopsis congesta var. pseudotypica). 



The appropriate state status of three species remains undetermined to date. These include: 

 Agastache foeniculum, Geum canadense, and Elatine americana. The first two are eastern 

 deciduous forest species whose documented distributions outside the District in eastern 

 Montana are under review. The latter is a minute aquatic plant which shows little response to 

 disturbance and is knouTi from a few widely-scattered locations in the state. Forest Service 

 T/E/S consideration is not appropriate as such for these three species, and their state statuses 

 remain under review. 



Many of the target species occupy successional habitats dictated by topographic and edaphic 

 features or by localized habitat features such as wetlands or well-developed woodlands, all of 

 which have not been well-studied in eastern Montana. Wetland and mesic woodland habitats 

 are particularly affected by surrounding land-use practices, so further investigation of these 

 status questions would be appropriate to consider as a management priority. The apparent 

 species' rarity may reflect habitat threats, patchy distribution patterns or simply a general lack 

 of botanical and vegetation information available for eastern Montana. 



While there are relatively few species that are globally rare in eastern Montana, and relatively 

 little public land, the scarcity of public land places a premium on identifying conservation 

 needs and priorities on the Custer National Forest districts in eastern Montana. In many 



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