While this is not globally rare, few other occurrences 

 are protected and documented on public lands in 

 Montana, and they are smaller or lower 

 quality/condition. The absence of surrounding natural 

 vegetation does constrain options for landscape-scale 

 management if not also its value in having landscape 

 context. Nevertheless, it provides a good rangeland 

 reference and ecological baseline. 



The RNA may contribute habitat to previously- 

 documented upland grassland bird Species of Special 

 Concern including Ferruginous Hawk, Burrowing Owl, 

 Loggerhead Shrike and Baird's Sparrow, but does not 

 contain the wetlands that provide primary habitat for 

 the waterfowl and colonial nesting birds found 

 elsewhere on the Refuge. Wildlife values were not 

 evaluated. 



intermedium) are at low levels within and outside the 

 RNA. The very aggressive yellow sweetclover 

 (MeUlotus officinalis) and crested wheatgrass (Agropyon 

 cristatum) probably pose greater threats in the long 

 term. A narrow band of encroaching crested wheatgrass 

 is found along the road grade disturbance zone along 

 the west boundary of the area. 



Historically, ftre and bison grazing were two major 

 driving forces in this landscape, responsible for 

 renewing the vigor of the grasses, stimulating forb 

 numbers, and keeping shrub density low. 

 Reintroduction of appropriately timed fire is a 

 management option to consider in containing nearby 

 weed populations and stimulating forbs; realizing that it 

 can help control or increase Bromus tectorum and 

 MeUlotus officinalis depending on conditions. 



OTHER VALUES: 



The RNA also preserves a segment of the Old MuUan 

 Trail, part of a 642 mile wagon road linking the 

 western-most navigable waters of the Missouri River at 

 Fort Benton with the eastern-most navigable waters of 

 the Columbia River at Walla Walla, Washington. 



LAND USE: 



Prior to and after refuge establishment in 1929, the 

 area was grazed as a part of a large common grazing 

 allotment. A summer-fall season grazing permit system 

 was instituted in the 1940s. After the refuge was staffed 

 and facilities developed in the early 1960s, a new 

 grazing management plan provided for a much-reduced 

 level of suimner and fall grazing. Although it is not 

 possible to determine the exact grazing regime applied 

 to the RNA, grazing on the whole refuge dropped from 

 about 2,700 animal utut months (AUMs) in 1960 to 

 1,631 AUMs in 1966. In 1976, livestock grazing was 

 terminated on the refuge, and the area has been rested 

 since that time. The existing composition suggests that 

 is was part of secondary range or more likely a relatively 

 recovered primary range in good condition. 



Since the time of RNA establishment, there has been 

 at least one experimental fertilizer application over 

 undefined segments of the area. Refuge records indicate 

 that it did not have the desired effect of increasing 

 productivity or stand structure, and was discontinued. 

 Records do not specify treatment area, application 

 concentrations, or include monitoring. 



MANAGEMENT COMMENTS: 

 Exotic species are uncommon at present. Although 

 both are present, populations of cheatgrass (Bromus 

 tectorum) and intermediate wheatgrass (Agropyron 



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