The World's Largest Public Domain Media Search Engine
Conserving globally rare plants on lands administered by the Dillon Office of the Bureau of Land Management (2003) (16042420994)


Conserving globally rare plants on lands administered by the Dillon Office of the Bureau of Land Management (2003) (16042420994)



Elymus flavescens
Title: Conserving globally rare plants on lands administered by the Dillon Office of the Bureau of Land Management
Identifier: 7A3084E0-64D5-462D-AFB1-40FDC685EE2D (find matches)
Year: 2003 (2000s)
Authors: Lesica, Peter; United States. Bureau of Land Management. Dillon Office
Subjects: Rare plants; Rare plants; Habitat conservation
Publisher: Helena, MT : Natural Heritage Program
Contributing Library: Montana State Library

Text Appearing Before Image:
Text Appearing After Image:
fendleri is sparsely distributed throughout much of western North America, but is known from only two widely separated areas of Montana. Elymus flavescens occurs in sandy soil in the northwest U.S., but in Montana occurs only in the Centennial Sandhills. All three species are found in the sandy soil of early-seral communities and are absent or rare in late-seral sagebrush steppe (Schassberger 1988). Succession will tend to diminish the amount of early- seral habitat. Disturbance regimes that create or maintain early-seral vegetation (fire, drought, gophers, grazing) will be necessary to preserve these rare species in the sandhills landscape. Conservation significance The Centennial Sandhills are the highest-elevation sandhills in Montana and the ^hmusflave7cens entire Northern Rocky Mountains. They support the only Montana populations of the globally rare Astragalus ceramicus var. apus, which occurs only in the Centennial Sandhills and the sandhills of southeastern Idaho. Elymus flavescens and Cryptantha fendleri, two other species found here, are more widespread globally but are highly restricted in Montana. The Centennial Sandhills also include the only Montana location for two plant communities, the Chrysothamnus viscidiflorus/Stipa comata and Artemisia tridentata tridentata/Stipa comata community types. The area also provides habitat for two animal Species of Concern: Preble's shrew and the Great Basin pocket mouse (Hendricks and Roedel 2002). Without special management, many of the biological values of this unique site could be lost. Management Maintaining the biological diversity of the Centennial Sandhills depends on maintaining a mosaic of different serai vegetation types. The three rare plants. Astragalus ceramicus var. apus, Cryptantha fendleri and Elymus flavescens, all require the open sand of early serai vegetation to persist. Late serai vegetation of the Sandhills, the Artemisia tridentata ssp. tridentata/Stipa comata association, is found nowhere else in Montana and may also harbor rare or unusual organisms. Disturbance regimes in the Centennial Sandhills have likely been altered significantly. Human fire suppression has been effective at reducing the frequency of wild fires in Montana over the past 50-60 years. Although there have been fires in the Centennial Sandhills during this time, it is likely that fire- return intervals have become longer. The intensity of grazing by bison in pre-European times is not known. We suspect that livestock densities (mainly sheep) were high, and grazing was season-long in the late 1800's and the early 1900's. Livestock grazing on public lands in the Sandhills has probably been more moderate in the past 50 years. Lower fire frequencies and moderate stocking rates have probably resulted in a decrease in early serai vegetation compared to presettlement conditions. Much of the eastern portion of the Sandhills, including Red Rock Lakes Wilderness, has lower topographic relief and is almost completely dominated by mid- to late serai vegetation. Pocket gophers are uncommon, probably due in part to the paucity of slope habitat. Of the three rare plant species, only Cryptantha fendleri was observed in this area. Controlled fire followed by intense livestock grazing for 1-2 years should significantly reduce vegetal cover, allow reinitiation of active blowouts, and ultimately increase the proportion of early serai vegetation. Returning to presettlement fire return intervals of 20-30 years and moderate ungulate grazing, at least in years following burns, will probably maintain a significant proportion of early serai vegetation. There is more topographic relief in the western third of the sandhills. Active blowouts, early serai vegetation, and pocket gophers are common. All three rare plants are present, although Elymus flavescens is uncommon. Gopher activity is an important force in initiating blowouts and maintaining early serai vegetation in this area. Managing for presettlement fire return intervals of 20-30 years should increase the proportion of mid-seral vegetation, thereby increasing pocket gopher habitat. Increased Appendix C - 16





Internet Archive

Copyright info

public domain

Explore more

2003 books
2003 books