Seedling establishment of wild and cultivated Leymus chinensis (Trin.) Tzvel. under different seeding depths

Seedling emergence, survivorship, and production of Leymus chinensis were monitored for 2 years at a semi-arid degraded steppe grassland site in northern China. Seeding depth (1, 2, 4, or 6 cm) and seed source (wild and cultivated) were used to study their effects and interaction on L. chinensis seedling establishment. Seeding depth negatively affected seedling emergence, seedling density, and shoot biomass. The highest emergence rate was 60% at a 1 cm seeding depth, and the lowest emergence rate was 13% at a 6 cm seeding depth. Seedling emergence rate of the cultivated seed source of L. chinensis was higher than the wild source. However, survivorship at the beginning of the second growing season was higher for the wild seed source than cultivated source. In the second year, plant density and shoot biomass were greater in plots planted at shallow seeding depths and with the wild seed source. Thus, the control of seed source and seeding depth are both critical in the revegetation process of degraded sites; however, seeding depth may be more important than seed source. Seeds from a wild seed source and a seeding depth of 1–2 cm can improve seedling establishment, growth, and yields of L. chinensis in semi-arid, degraded steppe grassland sites in northern China.