Pascopyrum smithii (well represented in our plot, constant in theirs), but differs in composition of 

 native forbs (they describe an abundance of Maianthemum stellatum in ungrazed habitat). The 

 eighteen stands sampled by Hansen et al. (1995) in Montana are more variable; only Populus 

 deltoides is 100 % constant. The successional sequence envisioned by Hansen et al.(1995) in the 

 absence of sediment deposition includes development of a lush, tall shrub layer characteristic of 

 stands of POPDEL / Cornus stolonifera followed by the Fraxinus pennsylvanica / Prunus virginiana 

 or Acer negundo / Prunus virginiana plant associations (depending on seed sources). The 

 development of these later or potential natural community stages as Hansen et al. (1995) envisage for 

 POPDEL/SYMOCC in Montana may be geomorphically, (climatically) or topographically limited. 

 This plant association also corresponds with the major subtype of the Cottonwood community 

 documented in southwestern North Dakota (Wall et al. 1980) which has a distinct tall shrub 

 component that includes Shepherdia argentea, Rosa woodsi and Salix amygdaloides. We interpret 

 their absence in the sample plot to reflect the increased aridity of the climate, perhaps a drier western 

 phase. Management of the sample stand as an exclosure could provide answers to questions 

 concerning management and classification of POPDEL/SYMOCC in Carter County. Further survey 

 for and sampling of this and other Cottonwood community types in Carter County on BLM lands is 

 identified as a tentative priority. 



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