Fraise Mowing as a Spring Transition Aid

摘要

Perennial ryegrass (Lolium perenne L.) often must be removed culturally or chemically from overseeded hybrid bermudagrass [Cynodon dactylon (L.) Pers. x Cynodon transvaalensis Burtt-Davy] in the spring. Fraise mowing has traditionally been used for shallow organic matter management. However, turfgrass managers are utilizing this novel cultural practice for additional uses including annual blue-grass (Poo annua L.) removal in cool-season turf. The objective of this study was to evaluate fraise mowingas a viable spring transition aid. Hybrid bermudagrass was overseeded with perennial ryegrass in the fall of 2016 and 2017. Fraise-mowing treatments were made at three depths (0.25, 0.5 and 0.75 inches) in May and June of 2017 and 2018. Perennial ryegrass-cover, bermudagrass-cover, and turfgrass quality (TQ) were assessed weekly after fraise mowing until late July each year. Intermediate and deep (0.5- and 0.75-inch) fraise mow treatments in May reduced perennial ryegrass cover compared with the untreated control. All fraise-mowing treatments performed in June resulted in decreased ryegrass cover. However, all treatments including untreated controls had no ryegrass present and > 90% bermudagrass cover in late July of both years. Unacceptable TQ (<6) followed fraise mowing at all depths. Fraise-mowing depth and timing impacted the duration of unacceptable TQ. The intermediate June fraise-mowing treatment effectively removed perennial ryegrass and had unacceptable TQ for the shortest duration after treatment. Fraise mowing at 0.5- or 0.75-inch depths provides turf managers with an effective cultural practice for removing perennial ryegrass from overseeded bermudagrass.