Native seed mix richness impacts revegetation of reclaimed land

Abstract

Interest in using native plant species for land reclamation and ecological restoration continues to increase. Yet sufficient knowledge of characteristics of native species for revegetation, specifically their response in field settings, continues to lag. Thus our study was conducted to determine whether the richness of native seed mixes impacted plant community development following reclamation in the Aspen Parkland ecoregion of Alberta, Canada. Four seed mixes were used: mix I with 6 grasses, mix II with 10 grasses, mix III with 6 grasses and 10 forbs, and mix IV with 10 grasses and 10 forbs. Each seed mix was designed with equal amounts of pure live seed for each species. After two growing seasons, seed mix richness generally had little or no effect on seeded species richness, individual seeded species, density, non-seeded species density, and ground cover, except for seeded forbs. Seed mixes II and III, with moderate species richness, provided the most benefit for developing species rich communities. Seeding with high species richness is more expensive, sometimes difficult to procure seed, and may not associate with communities of greater species richness, negating their need.