2022-10-26_PERMIT FILE - C1981041

• Permit No: C1981041
• IBM Index Class Name: Permit File
• Doc Date: 10/26/2022
• Section_Exhibit Name: Tab 10 Vegetation Information
• Media Type: D
• Archive: No

• 4.0 SUMMARY
A quantitative vegetation study was conducted in July 1982 at the Roadside
and Cameo No. 1 Mines, Mesa County, Colorado. The study was designed in
accordance with the "Regulations of the Colorado Mined Land Reclamation
Division, 1980" to establish a standard for measuring revegetation success.
Powderhorn Coal personnel and Colorado Mined Land Reclamation specialists
determined that data from these study areas would be appropriate for
establishing reclamation success standards.
This study quantitatively determined the vegetation cover, production,
density, and shrub heights for each of the three study areas and mapped
the entire permit area and some adjacent areas. Tables 15, 16, and 17,
respectively, summarize the cover, production, and shrub density and height
data.
All three study areas have high densities and sometimes extensive cover
of native shrubs.
The vegetation cover of the study area varies from a low of 34.8 percent
for Shadscale Shrubland to a high of 50.9 percent for Greasewood Shrubland.
Greasewood/Shadscale Grassland had a cover of 44.2. Litter and soil
cover are relatively high in all study areas while rock cover is high in
the Shadscale and Greasewood/Shadscale sites.
• The vegetation composition of these study areas has been greatly affected
by past disturbance, mc•st likely prolonged and intensive grazing by live-
stock. This has resulted in a'decrease in the cover of native grasses
and forbs. Today, introduced and native annual grasses and forbs account
for a significant portion of the herbaceous cover in all study areas.
Prohibited and restricted noxious weeds are frequent and there are no
threatened or endangered plant species.
Table 16 summarizes the production for the three study areas. Greasewood
Shrubland is the most productive at 466.2 Ibs/ac. The production in
Greasewood/Shadscale Grassland is very low at 142.0 Ibs/ac. Shadscale
Shrubland is also quite low at 164.4 Ibs/ac. As with cover, most of the
production comes from annual and perennial weedy species and annual grasses
all of which tend to be unpalatable to livestock.
The shrub density ranged from a low of 1635 for Shadscale Shrubland to
a high of 2315 for Greasewood Shrubland. Greasewood/Shadscale Grassland
was intermediate in density at 2040. All these study areas have probably
increased shrub densities today due to a selective advantage resulting
from overgrazing as livestock tend to graze on the herbaceous component
rather than the shrubs. Shrub heights were varied per study area but
tended to be higher in the Greasewood Shrubland and lowest in the Grease-
wood/Shadscale Grassland.
• Either statistical adequacy or the maximum number of samples was taken for
cover, production, and density.
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