PERMFILE48738

• Permit No: C1981026
• IBM Index Class Name: Permit File
• Doc Date: 12/11/2001
• Doc Name: FISH & WILDLIFE RESOURCES INFORMATION
• Section_Exhibit Name: APPENDIX G
• Media Type: D
• Archive: No

• a. Big sagebrush-grassland plateau
This type dominates the northeast portion of the
lease area, where the terrain is relatively flat and
soils relatively deep. The differentiation of sagebrush
and grassland can be made only on a subjective basis,
with the aspect dominance varying markedly in relation
to site factors and microclimate, and in the long term
with wild and domestic ungulate use. In general,
big sagebrush (Artemisia tridentata) tends to dominate
on well-drained sites which are relatively free of
snow. Perennial grasses dominate in snow accumulation
area and occupy the interspaces between shrubs.
The coverage of big sagebrush tends to increase
in proportion to livestock use, as the more palatable
grasses and forbs are removed. Likewise, the dominant
grass cover tends to change with livestock use, as
the more highly preferred species such as bluebunch
wheatgrass (Agropyron spicatum) and Idaho fescue
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such as Letterman needlegrass (Stipa Zettermanii) and
related species.
The lease area shows evidence of past and present
moderate to heavy grazing and is in a relative condition
of disclimax. Taking into account regional range studies,
and with reference to representative research natural
areas, it is believed that under climax conditions, this
habitat type would be dominated by bluebunch wheatgrass
and Idaho fescue. Following nearly a century of heavy
grazing in the region, these species have been markedly
reduced and now constitute only 2.6$ of the flora of the
lease area (see vegetation, Appendix F).
It is believed that big sagebrush, once predominant
on a site, is able to maintain itself in the presence of
continued grazing and in the absence of fire. Such has
been the pattern over much of the western range, with
• big sagebrush presently occupying many former grasslands.
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