The effects of disturbance type on seedling environment and establishment of alpine species with different physiological and life history traits were examined during a 2—yr study on the Beartooth Plateau in southwestern Montana, USA. We compared soil temperatures, water potentials, and nutrients on mineral soils of a gravel borrow area with those on highly organic soils of a Geum turf area. Seedling emergence, growth, and survival of six seeded species (Geum rossii, Artemisia scopulorum, Potentilla diversifolia, Sibbaldia procumbens, Deschampsia cespitosa, and Festuca idahoensis) and emergence and survival of five unseeded species (Draba crassifolia, Draba incerta, Cerastium arvense, Arenaria rubella, and Androsace septentrionalis) were evaluated on both areas. The effects of N and P nutrient addition and surface organic mulch on the soil environment and seedling establishment were evaluated on the borrow area, while differences between uncleared turf and turf cleared of vegetation were compared on the Geum turf area. Plots cleared of vegetation on the Geum turf area had higher levels of soil N (NO3—) and P than uncleared turf and both higher levels of N (NO3— + NH4+) and P and higher soil temperatures (surface, 5, and 15 cm depths) than fertilized or not—fertilized borrow area treatments. Fertilization increased N and P on borrow area soils, but after 2 yr N had decreased significantly. Soil water potentials (5 and 15 cm depths) did not differ between cleared plots on the Geum turf area or any of the borrow area treatments and were never low enough to cause plant stress. Vegetated Geum turf had significantly lower water potentials than cleared plots, especially late in the growing season. Mulch had no effect on soil water potential or nutrients on the borrow area and increased soil temperatures only on clear days during the first growing season. Wind removed or redistributed the mulch over time, thus decreasing potential effects. Seedling emergence was highly dependent on soil surface stabilization and reflected species life history traits. Growth of seedlings was slow, and varied among species and treatments: 0.005—0.04 and 0.02—0.20 g total mass after the first and second growing seasons, respectively. Significantly higher total seedling mass was observed on cleared Geum turf plots than on any of the borrow area treatments, and on fertilized than on not—fertilized plots on the borrow area. Seedling mortality of most species was much lower than previously found for alpine ecosystems, rarely exceeding 50% even after 2 yr. On the borrow area mulch increased survival, probably through microenvironmental amelioration. The nutrient pulse from fertilization mortality of several species, presumably by creating plant nutrient demands in excess of availability during year 2. Both disturbance characteristics and species life history and physiological traits affected seddling establishment. Pretreatment soil properties of the two disturbance types had the greatest effects on soil temperatures and nutrients and, consequentl...

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JEANNE C. CHAMBERS has been a range conservationist with the Mined-Land Reclamation research work unit at the Forestry Sciences Laboratory in Logan, Utah, since January 1981. She earned a B.S. degree in wildlife conservation and an M.S. degree in range sciences from Utah State University. Her research responsibilities currently involve sampling methodology and community ecology of alpine mined land. RAY W. BROWN is a plant physiologist on the Mined-Land Reclamation research work unit at the Forestry Sciences Laboratory in Logan, Utah. He joined the staff of the Intermountain Forest and Range Experiment Station in 1965. He holds a B.S. degree in forestry and an M.S. degree in range ecology from the University of Montana, and a Ph.D. degree in plant physiology from Utah State University. His main research responsibilities include plant water relations and mined-land revegetation in alpine and other high-elevation life-zones.

To evaluate reclamation success on the Wooley Valley phosphate mine in southeastern Idaho, we compared vegetation structure and soil physical, chemical, and elemental properties of several different reclamation treatments with those of a nearby reference area (a native Artemisia tridentata vaseyana/Festuca idahoensis association) after 14 years. Vegetation data had been collected four years after reclamation, and we were able to compare differences in biomass and species composition between dates on the reclaimed area. Four years after reclamation there were no differences in total biomass between topsoil or spoil or between seed only, seed + mulch, or control treatments on the different soil types. Most treatments were dominated by seeded perennial grasses. Fourteen years after reclamation there were no differences in biomass or cover between spoil and topsoil plots, but on spoil plots the seeded and mulched treatment had higher total biomass and vegetation cover than on control or seed‐only treatments. The seeded perennial legume Medicago sativa was codominant with the seeded forage grasses on all of the treatments. High initial fertilization rates probably facilitated the early establishment and dominance of the forage grasses; once nutrient levels, especially nitrogen, began to decline, the legume increased in abundance. Similarity between the reclaimed area and the reference or native area was low. Reclaimed treatments had higher biomass but lower species richness. The topsoil and spoil plots had similar soil texture, bulk density, pH, cation exchange capacity, electrical conductivity, and phosphorus. Differences in organic carbon, total nitrogen, carbon: nitrogen ratios, and available moisture were related more to treatments than to soil type. High biomass and, thus, litter input on the seed + mulch treatment on spoil plots resulted in both higher OC and TN than any on other soil/treatment combination. The reclaimed area had lower OC, TN, and available moisture than did the reference area on all but seed + mulch spoil plots. Bulk density was higher on reclaimed plots. The long‐term differences observed between the reclaimed and reference areas parallel those obtained for other western reclamation sites. Although successional trajectories depend on the attribute measured, similarity to native reference areas depends on the initial reclamation methods. We discuss reclamation methods that would increase the structural and functional similarity of reclaimed and reference areas on the Wooley Valley phosphate mine.