Stabilization of Great Lakes Sand Dunes: Effect of Planting Time, Mulches and Fertilizer on Seedling Establishment

Abstract

Studies were conducted to test the effect of planting time, mulches and fertilizer on seed germination and seedling establishment of Calamovilfa longifolia (Hook,) Scribn, and Ammophila breviligultua Fern, in a blowout along Lake Huron shoreline. Seeds were planted in June or October 1982 and covered with various mulches (sodium silicate, asphalt emulsion, wood chips, peat moss, straw, jute mesh, hydro mulch plus erosion blanket and control). Two other treatments (fertilizer and weekly watering) were also tested. Planting of grass seeds in October was more appropriate than the June planting because the seeds did not have to be artificially stratified and watering was not essential for seed germination and seedling emergence in spring. In 1982, about 2 to 26% of Ammophila breviligulata seedlings established in different treatments probably owing to shading by the sides of wooden frames and well distributed precipitation during summer. However, in summer 1983 with normal precipitation and natural dune environment, none of the seedlings survived in any of the treatments. It is suggested that A. breviligulata should not be planted from seed. In contrast, the seedling establishment of C. longifolia was rather high (7 to 96%) in different treatments in all three years. After 63 or 67 weeks of sowing, none of the mulch treatments was significantly better than control except jute mesh and erosion blanket for C. longifolia. The application of fertilizer resulted in larger seedlings than control at the end of one year.