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Sericea lespedeza [Lespedeza cuneata (Dum.-Cours.) G. Don], an exotic, drought-hardy perennial legume was first introduced into the United States from Japan. It was planted from the 1930s through the 1950s as a forage crop, for healing erosion scars on farmlands, establishing cover on mine spoils, and as cover for wildlife. The species range was unintentionally increased in the 1980s when seeds harvested from infested rangelands were planted on Conservation Reserve Program (CRP) acres. Sericea lespedeza has spread to extensive areas of native prairie and other lands not under cultivation in the more humid regions of the Great Plains in Texas, Oklahoma, Nebraska, Kansas, and eastward into Missouri and Iowa in the past decade. Left uncontrolled, the plants may dominate native grasslands. Hectares infested with sericea lespedeza in Kansas increased from 3,200 in 1988 to 187,492 in 2001, and it now occurs in 72 of the 105 counties. Seeds are disbursed primarily by wildlife and humans. Herbicides are available but expensive and often ineffective in long-term control. A potential biological control is the lespedeza webworm (Tetralopha scortealis Lederer, Family Pyralidae), a defoliating moth, larva that reduced seed production 98% in infested plants. Lespedeza webworms were successfully transplanted into a sericea lespedeza population not previously infested. Severe drought in 2001 reduced lespedeza webworm numbers by 87% to 100% in sites sampled in eastern Kansas.