| Summary: | Open pit coal mining at the Sheriff minesite, in Northeastern British Columbia's Coal Block, will be located in the upper reaches of the subalpine and portions of the alpine zones. Because of the adverse growth conditions of this site, reclamation after mining will present problems in using agronomic plant species adapted to lower elevations. This will especially be a problem with clover, alfalfa and other legumes. Moreover, the after-use of the mined land requires a stable plant community capable of supporting wildlife forage (essentially Woodland Caribou and Mountain Goats) at least to the same ability as the pre-mining communities. To deal with these constraints, and to re-establish native plant communities, it will be necessary to incorporate native species in the reclamation program. As a preliminary selection process, this study has pre-selected five native species on the basis of the constraints mentioned above. These species, Salix arctica, Dryas integrifolia, Hedysarum alpinum, Oxytropis sericea, podocarpa (Arctic willow, Mountain avens and three high altitude legumes, respectively) were grown on crushed shale (from the minesite) to test inhibitions to growth on simulated spoils. Mature plant portions were collected from the minesite, rooted in the shale under a mist system in five inch (13 cm) standard pots and then placed outdoors. An equal number of each plant species was grown on the top mineral horizon on which these plants normally grow (the control). No fertilizer was added to either growth medium, with the exception of Oxytropis podocarpa. Testing was carried out at the University of British Columbia for one summer; lack of reclamation sites at the minesite and acclimatization of the plants to site growth conditions did not allow for, or require site testing for growth response to the type of growth medium. Following the growth period, above ground biomass was clipped and weighed after oven drying. Soil fertility analyses were concurrently conducted on the shale and control growth media. Statistical comparison of biomass between the two growth media indicated no significant difference for Salix arctica, Hedysarum alpinum or Oxytropis sericea; these species can be applied in site tests when reclamation begins, though Salix will need to be placed where drainage is not excessive. The rooting problem of Oxytropis podocarpa will necessitate further testing of this species, though seed propagation may overcome this problem. Dryas should probably not be planted early in the reclamation program as its growth is inhibited on the less weathered shale. Forestry, Faculty of Graduate
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