Revegetation at Two Construction Sites in New Hampshire and Alaska

Revegetation techniques were investigated for gravel soils in cold regions. Two gravel soil test sites were established in Hanover, New Hampshire, and Fairbanks, Alaska. During three growing seasons, we studied the applicability and cost effectiveness of various nutrient sources and mulch materials. The nutrient sources included sewage sludge (at 40, 60 and 80 tons/acre) and commercial fertilizer (at 200, 400 and 600 lb/acre). The mulching materials were wood fiber mulch with various types of tackifiers, peat moss, and sewage sludge. The effects of refertilization during the second growing season were also studied. At both sites the use of sewage sludge produced superior results in many respects to the use of fertilizer at the application rates studied. Grasses receiving sludge showed better establishment rates and greater plant cover and growth, and were able to withstand the hot drying conditions encountered during the summer months. Slightly quicker grass establishment was noted at the higher rates of application of each nutrient source in Fairbanks, while grass establishment at all sludge rates was good in Hanover. All fertilizer treatments performed poorly in Hanover. No evidence of winter injury to the grasses was noted in any of the treatments. Supplemental applications of nitrogen fertilizer in Hanover during spring of the second growing season proved highly beneficial. The fertilizer helped maintain grass growth even during dry summer conditions. The mulches were applied at the rate of 2,000 lb/acre. They were found to be important in providing a more nearly optimum environment for seedling establishment. Wood fiber mulch and the commercial Wood Fiber Mulch 2000, generally, were the best performers.