Managed grazing in WICST prairies: Tradeoffs between plant functional diversity, forage availability, and resistance to weed invasion

To explore the relationships between plant functional diversity, forage production, and forage quality in native grasslands managed for sequential grazing, managed grazing was employed across a diversity gradient in reconstructed tallgrass prairie communities. A well-established switchgrass monoculture was compared to reconstructed (planted) prairies that had been seeded with varying levels of native plant functional diversity (including native C4 grasses, native C3 grasses, native forbs, and native legumes, and which were invaded over time by non-native C3 grasses and non-native legumes). Native legumes were interseeded across all diversity levels to test if this functional group can be successfully established in existing native grasslands and how increased legume cover affects forage production and quality. We hypothesized that:
• increased functional diversity would be correlated to increased forage production; and
• across diversity treatments, native legume interseeding would result in greater increases in forage quality and production in C4 monocultures than in diverse prairies.

Authors: Craig M. Maier, Daniel J. Undersander, Randall D. Jackson, Janet Hedtke, Josh Posner