RESULTS 



Ecological Results 



The following descriptions of 19 vegetation types represent most of the common, well-developed 

 habitats on BLM-administered lands in Carter County. These include 7 forest and woodland types, 6 

 shrubland types, and 8 graminoid- and forb- dominated types (Table 3). They are based on 52 semi- 

 quantitative plots that were established to document plant associations and community types on 

 BLM land in Carter County. The plots document representative stands judged to be in the highest 

 range condition and/or with the least weed infestations. Each vegetation type is described in terms of 

 environment, vegetation composition, and other observations. 



Of direct benefit to statewide vegetation classification, we document new plant associations, 

 recommend global and state rank changes to existing plant associations, and identify classification 

 research needs. There are three plant associations that are new to state vegetation classification 

 literature. There are at least fifteen vegetation types that were considered potentially imperiled or 

 vulnerable on a rangewide basis in provisional rankings (GRANKS=G2 or G3). This study and 

 related studies have provided the basis for changing the ranks in several cases to reflect that these 

 community types are more widespread than previously known. There are five plant associations 

 warranting classificafion research as to the fidelity and significance of the rhizomatous wheatgrass 

 component as it occurs in association with Artemisia tridentata ssp. wyomingensis, Atriplex 

 gardneri, Sarcobatus vermiculatus, Nasella viridula and as a single-species community dominant. 



In total, more than seventy distinct vegetation types in Carter County are documented or reported to 

 date, not just on BLM lands. The compiled information from this study, from observation, and from 

 the literature is presented in Table 4. These may be underestimates of community diversity given that 

 there are many miles of riparian corridor, bottomlands, and woody draws that are in private 

 ownership that were not considered. County-wide vegetation surveys have not been conducted for 

 other Montana counties so there is not a basis for comparing these results, but given the topographic 

 relief, wide variety of substrates, and extensive unbroken habitat, this number is likely to represent a 

 high figure. We highlight the significance and rank recommendations for plant associations below, 

 referring to the total number of documented types in the county unless otherwise stated. 



Forested types are sparsely represented on BLM holdings. Despite their limited extent, forest and 

 woodland types warrant attention as important wildlife habitat and because of their slow 

 regeneration. In addition, four of the six forest types on BLM lands in the county are currently rated 

 as potentially vulnerable (G3). In the course of this and other studies we encountered many 

 examples of two of these, PINPON / CARING and PINPON / SYMOCC, and suggest that these 

 types are more abundant and widespread than previously known, though they could be impacted by 

 invasion of exotic species. We suggest their rank be changed to potentially secure (G4), on the basis 

 of the southeastern Montana reconnaissance alone. 



Of the 10 woodland vegetation types, 5 are ranked G3 or higher, one is G4 and 4 have their G-rank 

 in question. All of these types are threatened by the invasion of exotics to varying degrees. Even the 

 JUNSCO/ORYMIC type occurs in a landscape where yellow sweetclover {Melilotus officinalis) is 



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