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7999 Soil Sampling: Seneca Mine, Hayden Colorado <br />Rock Fragments- Rock fragments average 40 percent and range 35 to 45 <br />• percent. Rock Fragments are predominantly cobble and stone size (75mm to <br />250mm and 250mm to 500mm) of sedimentary origin, primarily sandstone. <br />Structure- Structure of the subsoil is weak very coarse subangular blocky to <br />massive. Weak structure is developing as the result of drying and wetting of <br />the subsoil horizon throughout the year and to occasional freeze thaw cycles <br />within the soil profile. Such structure is typical of mechanically redistributed <br />subsoil. <br />Consistence- Dry consistence in the subsoil layer is very hard. Dry <br />consistence indicates moderate compaction through the use of mechanical <br />equipment for subsoil redistribution. Moist consistence is firm. <br />Lab Data- Lab data is located in Appendix II. The subsoil pH ranges 7.7 to <br />7.8 and averages 7.8 which is moderately alkaline. Organic matter averages <br />4.5 percent and ranges 4.2 to 4.8. These results and all other lab data <br />indicate subsoil in all sample pits as suitable (Appendix III, Table-2). <br />Vegetation- <br />Above Ground- At both sample pit locations, above ground foliar <br />development is fair for SEN-1-99 which is a grass/forb dryland site and good <br />• for SEN-2-99 which is a shrubland site. Plant form was typical for respective <br />species. Plant color is good and there is no color indications of mineral <br />deficiencies or toxicity. Soil lab data indicates that minerals are in sufficient <br />quantity to foster normal growth pattern. Plant vigor is fair for SEN-1-99. This <br />is likely due to moderate compaction. Plant vigor is good for shrubs at the <br />SEN-2-99 site. Ground cover is fair at both sites and a litter layer is starting to <br />develop. Small rills and gullies, probably the result of the runoff after initial <br />seeding have stopped and are filling with litter. <br />Below Ground- Root penetration into the upper topsoil is fair. Typically, roots <br />range common very fine, few fine and few medium roots typical of shrubs, <br />grasses and forbs in the initial stages of development. The lower topsoil has <br />roots starting to penetrate through the horizon with few very fine, fine and <br />medium roots. Root penetration should continue and even ameliorate soil <br />structure further. Roots are not matting along the upper topsoil/lower <br />topsoil/subsoil boundary indicating that root penetration will continue over <br />time. Root penetration into the upper part of the subsoil has not yet occurred. <br />Conclusions <br />Overall, topsoil and subsoil are suitable and are supporting a fair dryland pasture of <br />emergent grasses and forbs and a good stand of emergent shrubs. SEN-1-99 is <br />• shallow to cobble and stone spoil. This reduces available water holding capacity at <br />Page 7 of 11 <br />ovosioo <br />