Potential of several native and introduced warm season grasses as components of Silvopastures in the Southeastern United States

The goal of this study was to evaluate growth and nutritional characteristics of seven warm season grasses, including several natives, produced under simulated partial shading (50%) typical of loblolly pine silvopastoral systems in the southeastern United States. Forages included ‘Tifton 9’ bahiagrass (Paspalum notatum), ‘Tifton 85’ bermudagrass (Cynodon dactylon), ‘Alamo’ switchgrass (Panicum virgatum), ‘Kaw’ Big Bluestem (Andropogon gerardii), ‘Americus’ Indiangrass (Sorghastrum nutans), ‘Harrison’ Florida paspalum (Paspalum floridanum), and Nacogdoches Eastern gamagrass (Tripsacum dactyloides). Shade affected several quality parameters, including crude protein (CP) (p?<?0.0001), acid detergent fiber (ADF) (p?=?0.0413), in vitro true digestibility (IVTD) (p?<?0.0001), and total digestible nutrients (TDN) (p?=?0.0132). Shade affected the parameters differently depending on forage type, but generally improved quality by increasing CP, IVTD, and TDN; however, shade significantly increased ADF (p?=?0.0413), though the magnitude was small (344.2 vs. 351.1 g kg^?1), and increases were isolated to big bluestem and bahiagrass. Shade reduced dry matter yield (DMY) (p?<?0.0001), and there were differences among forage species (p?<?0.0001). Bahiagrass and Florida paspalum showed the highest yields, regardless of shade treatment. Gamagrass and Florida paspalum would likely have performed better if harvested by days of rest, instead of by height. These could be viable forage species to a silvopasture system, but further studies should be conducted. Based on overall quality and yield, potential beef cattle gains, and persistence under intensive defoliation, the best forage was bahiagrass (introduced), and the best selections for native grasses were switchgrass and Indiangrass. These results indicate that there is potential for several warm season forages, including native grasses, to maintain productivity and quality under shade, which would increase the site-specific options for forage selections in this system.