Biology and control of cogongrass (Imperata cylindrica) in southern forests
Cogongrass (Imperata cylindrica (L.) Beauv.) is a warmseason perennial grass species found throughout tropical and sub-tropical regions of the world (Hubbard 1944). Native to Southeast Asia, cogongrass is an aggressive invasive plant that that has spread to all continents except Antarctica (MacDonald 2004) and is considered among the worst problematic weeds on a global scale (Holm et al. 1977). In the United States, it is naturalized in Virginia, North Carolina, South Carolina, Georgia, Florida, Alabama, Mississippi, Louisiana, Texas, and Oregon (USDA Plants 2017). It was first accidentally introduced in the United States near Mobile Alabama in 1912 (Tabor 1949 and 1952, Dickens 1974) and subsequently intentionally introduced from the Philippines into Mississippi as a forage crop in 1921 (Tabor 1949 and 1952, Patterson et al. 1979, Tanner and Werner 1986). Plants from Mississippi were replanted in Florida for forage and soil stabilization in the 1930s (Tabor 1949, Hall 1983, USDA NISIC 2017), though its high silica and low protein content made cogongrass an inadequate forage crop (Coile and Shilling 1993, Garrity et al. 1993). These early regional introductions contributed to the establishment of cogongrass in the Southeast. Points of introduction, including forage trials, are often areas where cogongrass remains most well established (Willard et al. 1990). Cogongrass is regulated as a federal noxious weed (USDA Plants 2017).