The Research Ranch is dominated by native grasses. However, Lehmann Lovegrass (Eragrostis lehmanniana) and Boer Lovegrass (E. curvula var. conferta = E. chloromelas), both native to South Africa, were planted in 1949 on approximately 400 acres of what is now the Research Ranch. In 2000, these species were mapped on approximately 2,000 acres. Studies have shown areas dominated by these exotic species support fewer native plant and animal species than native grasslands.
Reestablishment of native grass first requires control or elimination of the undesirable species. Currently, we use Glyphosate at 2% and individually spray each exotic, taking care not to spray any native species. This is extremely labor intensive, but we feel it presents the minimum amount of disturbance to the ecosystem. Simultaneously, we are researching to find other means to control the spread of these exotic species.
To reestablish natives, we harvest seed from sideoats grama, green sprangletop, plains lovegrass, cane beardgrass and other native species within existing stands on the Ranch, then sow this site-adapted native seed into areas recently dominated by exotic lovegrasses. Actively sowing each area with a mixture of desireable seeds, rather than depending on natural dispersal mechanisms, will reduce the exotic grasses' opportunity to recolonize areas.
Audubon Research Ranch Exotic Grasses