Bermudagrass–White Clover–Bluegrass Sward Production and Botanical Dynamics

Cool‐season forages dominate pastures in the Appalachian region where midsummer weather conditions often depress productivity. Warm‐season forages can buffer variation in available herbage, but land resources may limit the area dedicated to special‐use crops. A replicated field plot experiment was conducted for 3 yr (1995–1997) in a bermudagrass (Cynodon dactylonL.) stand oversown with Kentucky bluegrass (Poa pratensisL.) and white clover (Trifolium repensL.) to determine the influence of defoliation on productivity, nutritive value, and botanical dynamics of the mixture. Botanical composition changed with defoliation and varied among years. Bermudagrass comprised as much as 55% of the sward in mid‐ and late‐season 1995. By 1997, the proportion was similar to other grasses and rarely exceeded 20%. Maximum instantaneous growth rates occurred later in the growing season in 1995 when bermudagrass was a dominant sward component compared with subsequent years when bermudagrass was <10% of the sward. Rates in 1995 were greatest for swards clipped at 6‐wk intervals (70 kg ha−1d−1) or when 20‐cm tall and least when clipped at 2‐wk intervals (33 kg ha−1d−1) and at 10‐cm height (45 kg ha−1d−1). The trend was reversed by 1997 when sward composition shifted away from bermudagrass to cool‐season grasses and white clover. Yields were greatest when cool‐season species dominated the sward. Creating a self‐regulating mixture of warm‐ and cool‐season perennial forages may be a means of achieving some stability in sward productivity and might be useful where wide fluctuations in growing conditions occur among years.