Enhanced Establishment of Native Warm-Season Forage Grasses Using Seedling Transplants.

To asses alternative establishment approach for native warm-season forage grasses in southeastern USA, high-tunnel raised 6-week old seedlings of Andropogon gerardii (big bluestem), Tripsacum dactyloides (eastern gamagrass), Sorghastrum nutans (indiangrass) and Panicum virgatum (switchgrass), were transplanted to clean seedbeds in June, spaced 30 and 45 cm within and between rows, respectively. In the same summer, control plots were seeded ≤ 2 cm deep for comparison. As needed, tall-growing broadleaf weeds were manually controlled by chopping them down with a hoe. In the first year, plants were allowed to grow undisturbed and early in the succeeding spring, dead standing biomass was mowed down. Sward heights were recorded at boot and full bloom stages. Plots were harvested by machine to determine dry matter yield per area, after which 7-day regrowth heights were recorded. No fertilizers were applied. Data were analyzed as a randomized complete block design for effects of planting methods within species and that of species within planting methods in four replications. Generally, plants were healthier in transplanted than seeded plots which suffered more weed competition. Plant heights, at boot stage, were greater in transplanted than seeded plots, except for indiangrass. Mean height at full bloom was shortest for seeded indiangrass (75 cm) and tallest for transplanted switchgrass and big bluestem (average, 180 cm). Except for switchgrass, regrowths were 5-, 11-, and 14-cm taller in transplanted than seeded plots for indiangrass, gamagrass, and big bluestem, respectively. Data indicate that transplanting, under similar growing conditions, may be a reliable strategy to successfully establish native warm-season grass stands in one year. Strategies to support faster growth and control weeds during establishment are also needed.