Road Ecology Center

The Federal Highway Administration (FHWA) Central Federal Lands Highway Division is conducting a comprehensive study to identify techniques that maximize the opportunities for successful revegetation along high altitude portions of U.S. Highway 212, the Beartooth Highway. A portion of the Beartooth Highway that travels through alpine and subalpine areas is proposed for reconstruction by the FHWA. FHWA has conducted revegetation experiments in the form of test plots and seed-increase experiments since 1999 to identify the most successful revegetation techniques for revegetating alpine areas. Over a period of four years, four revegetation experiments have been placed on the Beartooth Highway to investigate the most effective revegetation techniques for subalpine and alpine disturbances. Variables tested include topsoil placement, organic amendments, surface mulches, seeding rate, and seed source (locally collected or commercial sources). In addition, three seed-growout experiments have been conducted at a nearby farm in Manderson, Wyoming, to assess whether seed collected on the Beartooth Plateau can be produced in large quantities and used to revegetate disturbed areas associated with construction. These seed-growout experiments tested the potential to commercially produce a variety of alpine and subalpine forb, grass, and sedge seed. The results from this study will assist highway departments, mining, oil and gas, and utility companies, and other land-management agencies in revegetating high-altitude disturbances to meet requirements of various state, local, and federal permits. The study makes conclusions about the effectiveness of several revegetation items, such as seeding rate, type of organic amendment, fertilizer reapplication, and topsoil placement and makes recommendations for further study regarding native-seed propagation. Key words: alpine revegetation, native-plant restoration, highway revegetation, soil amendments, seeding rates, topsoil.