Methods to increase native warm-season grass diversity in bermudagrass

摘要

Bermudagrass [Cynodondactylon (L.) Pers. ] is the most common warm-season introduced forage species grown in the southern portion of the United States. Often grown as a monoculture, bermudagrass responds well to fertilizer and intensive management butprovides little wildlife or microbial soil community benefits due to the lack of species diversity. A methods study to evaluate methods of increasing diversity of bermudagrass by adding switchgrass (SG) or a native warm-season grass mixture (NGMIX) wasconducted in southern Oklahoma. An established bermudgrass stand was suppressed using either 7, 11, or 19 months of seedbed preparation time (PREP) with either zero, one, two, or three cover crops depending on PREP time and applied to either till or no-till strips. Initiation of PREP times were staggered so a common date for SG and NGMIX planting was achieved in two consecutive planting years, April 2011 (Year 1) and April 2012 (Year 2). On both soil textures, till establishment increased stand frequency of SG and NGMIX the year of establishment compared to no-till. Stand frequency was repeated in 2015 (3 and 4 years post planting, respectively). The loam soil, no-till stand frequency counts in 2015 had improved for SG and NGMIX and were similar to till. The sandy loam site 2015 stand frequency counts of till established SG and NGMIX remained higher than no-till. No-till establishment was slower than and not as successful as till but it still achieved plant diversity in bermudagrass at a lower cost compared to till. Cover crops and PREP time had little effect on establishment.