1987-12-01_PERMIT FILE - C1981017 ‎(245)‎

• Permit No: C1981017
• IBM Index Class Name: PERMIT FILE
• Doc Date: 12/1/1987
• Doc Name: Vegetation Inventory Reference Area Establishment
• Section_Exhibit Name: Chapter III Appendix III-H-1
• Media Type: D
• Archive: No

• Tree density data in reference areas were obtained using two
methods. Aspen Woodland and Aspen Shrubland reference areas were sampled
using the point—centered quarter method described in Section 2.2.4 above.
Because of the patchiness of Spruce/Fir Parkland, a total census method was
employed. This technique consisted of counting all individuals and dividing
the total for each species by the total area (3 acres = 12,140 m2) . Diameters
were also measured for all trees in each reference area.
Sample adequacy for reference area production used the OSM formula
described above. However, reference area cover and shrub density data were
collected in 1979, prior to the publication of OSM's recommendation. There—
fore, adequacy for these data were calculated with a somewhat different
formula,
2(sz)2
nmin (dx)2
where s = sample standard deviation, z = 1.28 (cover) and 0.84 (shrub
density) , and d = 0.1 (cover) and 0.2 (shrub density) . Tree density adequacy
for Aspen Woodland also used this formula, while densities for the other two
reference areas were based on total counts.
2.4 Plant Species Inventory
Specimens of vascular plants were collected each field trip
during both the 1979 and 1980 growing seasons. Field identifications were
verified by Dr. William A. Weber, Curator of the University of Colorado
Herbarium in Boulder.
In addition to a thorough species list for the study area, the plant
inventory provided information on the occurrence of noxious weeds and the
actual or potential presence of species designated as threatened or endangered.
2.5 Timing of Sampling
Cover and woody plant data for reference areas were collected late in the
1979 growing season. production data for reference areas, as well as cover ,
production, and woody plant data for affected areas were collected during the
middle and late growing season in 1980. Species inventories were conducted
in conjunction with each of the sampling efforts; additional field trips for
the species inventory were conducted in fall 1979 and late spring and early
summer 1980.
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