low cover here would not necessarily indicate 

 overgrazing at present or in the recent past. Scarlet 

 globemallow (Sphaeralcea coccinea) is a forb found here 

 and across all maimer of range sites. [Plot 

 NHMTECRN98SC0008] 



Sdpa comata - Bouteloua gracilis - Carex filifoUa 



Herbaceous Vegetation 



[STICOM - BOUGRA - CARFIL] 



needle-and-thread - blue grama - threadleaved sedge 



This is one of the most extensive of Great Plains 

 grassland community types, occurring from the 

 Midwest to the Rocky Mountain Front of Montana and 

 north well into Saskatchewan and Alberta. In eastern 

 Montana and North Dakota it occurs, as at this site, on 

 soils with a higher percentage of sand than is 

 represented in soils of adjacent communities; it occurs 

 on both glaciated and unglaciated landscapes. In 

 eastern Montana landscapes these sites are frequently 

 on ridge systems where sandstone strata are exposed. 

 In the shale- and siltstone-dominated plaiiw of eastern 

 Montana it is often maiufested as a small patch type on 

 projecting ridge crowns and hillocks. 



It has also been the subject of some vegetation 

 classification uncertainty because there have also been 

 two other plant associations named with needle-and- 

 thread in separate combination with the two other 

 species. There is no existing unequivocal key to 

 vegetation types that can distinguish among these 

 types, so the most inclusive name was chosen, one that 

 appears to fit published descriptions of the type (Allen 

 et al. 1999). This type is potentially extensive on the 

 sandstone-underlain benchlands that cap the local 

 landscape. It is in particularly good condition as it 

 occurss within the RNA whereas this type has 

 undergone a grazing-induced conversion to a fringed 

 sage (Artemisia frigida) and blue grama {Bouteloua 

 gracilis) -dominated disclimax on directly adjoining 

 tracts separated by fence. Litter and lichens dominate 

 the ground cover within the RNA type and are a 

 decidedly reduced outside the fenceline, where exposed 

 soil is the dominant surface category. 



Within the RNA's expression of this type, Artemisia 

 frigida is the only shrub-like plant, present in trace 

 amounts. Needle-and-thread (Stipa comata) strongly 

 dominates the herbaceous component. Throughout this 

 grassland, threadleaved sedge (Carex filifolia) has cover 

 values ranging from 50 to 70 %, though blue grama 

 (Bouteloua gracilis) , is still an important component. 

 Western wheatgrass (Pascofryrum smithii) is consistently 



present m trace amounts m contrast to its greater cover 

 on adjacent heavier-textured soils. There are no forbs 

 with greater than trace amounts of cover; those noted 

 to have with high constancy in this type and present 

 throughout the stand are rush skeletonweed 

 (Lygodesrrm juncea) and scarlet globemallow 

 (Sphaeralcea coccitKa) . (Plot NHMTECRN98SC0006 ) 



Fraxinus penr^sylvaruca I Prunus vir^rwma Temporarily 



Flooded Forest 



[FRAPEN/PRUVIR] 



green ash / chokecherry temporarily flooded forest 



Typically this type occurs along riparian corridors, 

 springs and ponds and other floodplain positions, but in 

 this landscape it is associated with v-shaped ravines 

 known colloquially as "woody draws". It is very similar 

 to the green ash-American elm/ western snowberry 

 forest (Froxtnus penrxsrjlvaruca - Vlmus americana I 

 Symphoricarpos occiderualis Forest) identified for North 

 and South Dakota, though in Montana only slightly 

 more than 10% of the stands of this type have Ulmus 

 americana present. Most of this stand is confined to the 

 ravine bottom and toeslope positions. The forest floor 

 is nearly completely covered with litter, the limited 

 ungulate trails being the only areas where soil that is 

 sandstone-derived, fine sandy loam is exposed. This 

 example of the type is of good to moderate quality due 

 to the dominance of the alien Poa prater^sis (Kentucky 

 bluegrass) and the somewhat low diversity of the forb 

 component, though noxious weeds are not present 



The upper canopy is rather open, appropriately 

 classified as woodland cover (40-60%) and height (25 

 ft.), with Fraxinus pennsylvaruca generally the dominant 

 tree species, as well as being represented in all layers of 

 the multi-storied canopy. Conks (bracket fungi) were 

 present on almost all larger Fraxim« stems, though 

 elevated mortality rates were not evident. In some 

 portions of the stand quaking aspen (Populus 

 tremuloides) is codominant with the Fraxinus. Both 

 Populus tremuloi^ and Rocky Mountain juniper 

 Quniperus scopulorum) also occur in multiple size classes 

 throughout the stand. The shrub component is 

 relatively diverse with at least seven species 

 consistently represented. Common juniper (Juniperus 

 commujus) and western snowberry (Symphoricarpos 

 occiderualis) are the dominants, but if the browsing 

 pressure on chokecherry (Prunus virginiana) and 

 western serviceberry (Amelanchier alrdfolia) were 

 relaxed, it is possible that these species might increase 

 in cover. Past disturbance is probably the reason that 

 Kentucky bluegrass (Poa pratensis) is the dominant 

 grass. Other important grasses are Canada wildrye 



31 



