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Soils at the Trapper Mine have physical and chemical properties similar to Colowyo (Table 7). Soil pH ranges <br />from 6.9 to 7.7. Macronutrients appear to be adequate for sustained plant growth, except for phosphorus. <br />Phosphorus levels are substantially lower at Trapper (0.2 to 3.1 mg/kg) compared to Colowyo (7.8 to 29.0 <br />mg/kg). A phosphorus level considered to be adequate for plant growth is about 7 mg/kg. Organic matter <br />levels are higher at Trapper compared to Colowyo, with values ranging from 4.8% to 6.5%. Salt <br />concentrations are low (EC ranges from 0.6 to 1.6 mmhos/cm and SAR ranges from 0.6 to 1.8) and CEC is <br />in a normal range. Textures are clay loam and sandy clay loam. <br />Comparisons between topsoil and spoil at Trapper indicate that pH is slightly higher in spoil (7.6 to 7.7) <br />compared to topsoil (6.9 to 7.1), NH4-N levels average about the same between spoil and topsoil and N03- <br />N levels are higher in topsoil (6.8 to 15 mg/kg) compared to spoil (6.3 to 7.7 mg/kg). Phosphorus levels are <br />substantially lower in spoil (0.2 to 0.5 mg/kg) compared to topsoil (2.6 to 3.1 mg/kg) and both are considered <br />to be low. Potassium levels are also much lower in spoil (76 to 118 mg/kg) compared to topsoil (193 to 428 <br />mg/kg). Electrical conductivity, SAR, CEC and texture are similar between topsoil and spoil. The only <br />chemical properties that appear to be markedly different between topsoil and spoil at Trapper are N03-N, <br />phosphorus, and potassium levels. <br />Soils at the Seneca Mine are also similar to Colowyo and Trapper (Table 8). Soil pH ranges from 6.8 to 7.6. <br />Macronutrients appear to be adequate for sustained plant growth, except for phosphorus. Phosphorus levels <br />are more similar to Trapper than Colowyo. Phosphorus concentrations range from 0.4 to 4.3 mg/kg at <br />Seneca. Organic matter levels are lowest at Seneca and range from 3.2% to 3.9%. Salt concentrations are low <br />(EC ranges from 0.3 to 0.9 mmhos/cm and SAR ranges from 0.3 to 0.6) and CEC is in a normal range. <br />Textures are clay loam and loam. <br />Spoil material at Seneca has lower pH than topsoil (6.8 compared to an average of 7.5) and lower phosphorus <br />levels (0.4 compared to an average of 3.1 mg/kg). Ammonium-nitrogen levels are similar between topsoil (4.1 <br />to 5.1 mg/kg) and spoil (4.6 mg/kg), as are N03-N levels (4.6 to 13.1 mg/kg in topsoil and 7.5 mg/kg in <br />spoil). Organic matter levels in topsoil range from 3.2 to 3.9% and the organic matter level in spoil is 3.2%. <br />Potassium levels, CEC, EC, and SAR are all similar between topsoil and spoil. Texture of spoil is loam and <br />clay loam in topsoil. Phosphorus and pH are the only two soil properties that appear to be different between <br />topsoil and spoil at Seneca. <br />In summary, topsoil and spoil at all mine sites were found to have favorable characteristics for plant growth, <br />with the possible exception of phosphorus at Trapper and Seneca. However, plant growth from previous <br />reclamation efforts has not shown evidence of phosphorus deficiencies and so it has been assumed that <br />phosphorus levels are adequate. <br />Vegetation Sampling <br />In July of each year (2000 through 2004) demonstration plots were sampled for vegetative cover by species, <br />bare ground, rock and litter using a point-intercept method. Sampling was stratified in the fenced and non- <br />fenced areas in order to examine the effects of game exclusion. Within each fenced (five plots) and unfenced <br />(five plots) plot at Colowyo and Trapper Mines (Figures 1 and 2), five 50-m transects were randomly located. <br />One of the five transects in each plot at Trapper Mine was stratified in mycorrhizae inoculation strips in order <br />to test for a treatment response. Cover data was collected every one meter along each transects (250 cover <br />points per plot). At the Seneca Mine, where plots are considerably smaller (Figure 3), we used three 30-m <br />transects and collected cover data every one meter (90 cover points per plot). Only three plots at the Seneca <br />Mine were divided into subplots by a fence. <br />In addition to cover sampling along these transects, we estimated shrub establishment and shrub height in <br />each demonstration plot within 0.5m2 quadrats along each transect. At Colowyo and Trapper, the quadrats