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Restoration of Native Grasses on the Research Ranch

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. We anticipate that over the past three years (2000-2003) the impact area has nearly doubled. 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 Roundup 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 will 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.

Anticipated negative effects are minimal. By harvesting seeds on a nearby approximately 100 acre native mesa, we will slightly reduce the seed crop available there for grasshoppers, mice, and overwintering birds. This will not impact the grass plants themselves, as these are established perennial grasses that do not depend on annual seed production to survive. We feel the harvesting of the seed crop is an acceptable impact over a limited area and that its potential benefit is enormous in that it allows site-adapted seeds to be used in the site restoration.