PERMFILE67186

• Permit No: C1981028
• IBM Index Class Name: Permit File
• Doc Date: 6/15/2006
• Doc Name: Revegetation Success Criteria
• Section_Exhibit Name: Appendix TR-37
• Media Type: D
• Archive: No

. correlation coefficients aze high (R2~.8059 and 0.8446). Individual plots of the
reclamation azeas for cover and the precipitation regimes also show low variation in the
curves and very similaz responses to increases in precipitation (Figures 26 and 28).

The plots of total herbaceous production for the 1985, 1986 and 1987 reclamation azeas
and the two precipitation regimes (Figures 29 through 32) reflect similar results as those
for total vegetation cover. Second order polynomial curves over the data range reveal
increasing production with increased precipitation. Unlike the cover plots, total
herbaceous production rates are increasing with increased precipitation over the data
range, indicating that total herbaceous production responds in a different manner than
total vegetation cover. Both precipitation regime plots reveal very high levels of
correlation (R2=0.9494 and 0.9431).
The following table compares the values of the best-fit curves and those more closely
representing predicted relationships for the 1985, 1986, and 1987 reclamation areas, the
two parameters, and the two precipitation regimes.
Parameter reci nation Re ime Third Order RZ Second Order RZ
Total Ve etation Cover Janu -Jul O.8S97 0.8059
Total V etation Cover Se tember-Jul 0.9327 0.8446
Total Herbaceous Production Janu -Jul 0.9654 0.9494
Total Herbaceous Production Se tember-Jul 0.9654 0.9431
The differences in explained variation range from 1.60 percent (Total Herbaceous
Production/January-July) to 8.91 percent (Total Vegetation Cover/September-July).
3.7 Species Composition
Table 5. identifies all species encountered in quantitative cover sampling at the Osgood
sand reference azea during the period of record (1994-2001). The total number of plant
species encountered during sampling over the period between 1994 and 2001 at the
reference area was twenty-five. Yearly total numbers of species ranged from seven (1994,
2000) to eighteen (1995). Of the species encountered during the period of record, only
five were present during every season sampling was conducted, Andropogon hallii,
Bouteloua gracilis, Calamovilfa longifolia, Stipa comatafviridula. and Artemisia filifolia.
Of the remaining species, those that were present for fifty percent or more of the years
included, Bromus tectorum (six of eight yeazs), Erigeron bellidiastrum (five of eight
years), Helianthus anrruus (five of eight years), Agropyron smithii (four of eight years),
and J.crppula redowskii (four of eight years).
Figure 33 presents the numerical data from Table 5 in a more visual format. Note that the
relative cover axis is logarithmic, further revealing the dominance of Artemisia filifolia.
From the Table S data, the species that consistently provided three percent relative cover
• or greater were identified and plotted on Figure 34. Bromus tectorum was added to show
the invasive and pervasive nature of this annual grass in the native community over time.
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