DISCUSSION 



A biodiversity picture of Carter County emerges in piecing together the ecological and botanical 

 results of this study. In it we identify the priority features, working toward a cohesive view of what is 

 truly rare on BLM-administered lands and the state as a whole and the relative significance of BLM 

 lands in the sustainability of these features across the county and state. The immediate products are 

 recommendations for deleting and adding sensitive species, the tools for identifying them in the 

 field, a reference for coordinating with other natural resource agencies in the state on vegetation and 

 sensitive species, and a body of reference information for management planning. 



The Carter County total of 1 8 Montana plant species of special concern represents the highest 

 number of rare Great Plains found in any single county of Montana, explained by the county location 

 as well as its diversity of plains habitat. Nine of these species are on BLM-administered lands. Two 

 of these are regional endemics, Visher's buckwheat (Eriogonum visheri) and bladder twinpod 

 (Physaria brassicoides), that are known from Montana only in Carter County. Three of the 18 

 species occur only on BLM lands among public lands in the county, including raceme milkvetch 

 (Astragalus racemosus), Visher's buckwheat {Eriogonum visheri), and bur oak (Quercus 

 macrocarpa); possibly also blue toadflax (Linaria canadensis var. texana). Immediate threats were 

 not identified for any of the nine species, except that two populations of narrow-leaved milkweed 

 (Asclepias stenophylla) are in apparent decline. 



The results from this study do not mean that each occurrence of the species regarded as rare need 

 fences around them now that the have been "discovered." Instead, the information is to be taken as 

 indication that the lands may represent something unusual. These species are all habitat specialists 

 that tell a story about range sites and plant associations. This information can potentially be used to 

 avert endangerment, maintain the vigor of species at geographic outposts that are intergral to overall 

 conservation, and come to better terms of appreciation for the diversity scattered across the plains. 



The total number of vascular plant species known to date from Carter County (507) is a significant 

 fraction (over 20%) of the species known in the entire state. It is only a preliminary flora because it 

 represents floristic documentation that was a secondary part of the studies, and it represents a 

 compilation drawing from public lands studies. Nevertheless, it presents a basis for comparison with 

 the more completely inventoried counties in South Dakota, North Dakota and Wyoming, as well as a 

 future reference in eastern Montana where county floras have not been prepared. At least as 

 significant as the diversity of native species is the relative paucity of noxious weeds. Apart from the 

 species of special concern, the native flora may not warrant single-species attention but ongoing 

 weed control vigilance and maintenance of the natural vegetation. 



It has been remarked "vegetation, more than any other biotic feature, gives character to the 

 landscape" (Knight 1996) and Carter County is distinguished by expansive tracts of intact native 

 plains vegetation, rendering this one of the most intriguing of landscapes. We have made huge 

 strides in documenting the vegetation. The most heartening result of this study on BLM- 

 administered lands is that it has become evident that a number of plant associations considered 

 potentially vulnerable (ranked G1-G3) may be more widespread than previously known and are 

 recommended for ranks changes to G4 or G5 as discussed below. 



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