(USDA/NRCS) — Indiangrass (Sorghastrum nutans) is a native, warm-season perennial grass that occurs across most of the United States east of the Rocky Mountains. It is commonly found in several ecosystems, including tallgrass prairie, savannahs, and as an understory component in southeastern pine forests across the South. In pine forests, it provides nesting habitat for game birds and songbirds, cover and concealment for other wildlife, and is an important component of the natural fuel load needed for successful prescribed burning practices. Indiangrass can also be used as a forage crop for both grazing and hay or as a component of native pollinator habitat mixes.
One of the most important decisions a landowner or conservationist must make when planning to utilize native plants, cover crops, or cash crops is selecting the best-adapted cultivars and/or seed sources that meet their planting objective(s). Using Indiangrass seed from a source not well-adapted to a specific region has resulted in stands with poor growth potential, lacks persistence, and often requires replanting after a few years. To identify well-adapted seed sources for the Deep South, the USDA-NRCS Jimmy Carter Plant Materials Center (PMC) in Americus, Georgia, evaluated four Indiangrass selections released by PMCs to determine their suitability for large scale conservation plantings. Releases included ‘Americus’, which originated from seed sources in Georgia and Alabama, Wynia Germplasm from seed sources in Arkansas and Eastern Oklahoma, ‘Rumsey’ from a seed source in Illinois, and ‘Cheyenne’ from seed sources in western Oklahoma.
The four releases were planted on an upland site, indicative of the coastal plain soils that are prevalent across the Deep South. Indiangrasses were evaluated for plant growth indicators such as plant height, plant vigor, maturity, and persistence. After three years of evaluation, both ‘Americus’ and Wynia Germplasm exhibited great persistence, good vigor, and high levels of plant growth indicating that they are well adapted to the soil conditions and climate of the region. The other releases, with seed sources further from Georgia, exhibited lower plant vigor and thinning stands by the third year, as well as less total plant growth overall.
It is vital to the success of conservation plantings that seed sources are well-adapted to the soil and climatic condition of the region. The Jimmy Carter Plant Materials Center identified two Indiangrass releases that are well-adapted to the Deep South. ‘Americus’ and Wynia Germplasm were more vigorous, exhibited better persistence, and had greater productivity potential, than Indiangrass cultivars that originated from the Southern Plains and Midwestern U.S.
For more information on the results of these evaluations, Click Here.
Source: USDA/Natural Resources Conservation Service