Effect Of Mowing Frequency And Nitrogen Application Quantity On The Species Changing Of Bermudagrass Overseeding Turf In Spring

In the climatic transition areas of the lower-middle reaches of the Yangtze River, overseeding Warm-season turf with cool-season turf in autumn fall is an effective method to maintain the turf green in winter, and extending the turf green throughout the year. The previous studies and practices have shown that whether the overseeding technology is successful or not depends on two factors, one is that the overseeding turf established or not before winter, the other is that whether the overseeding turf could successfully finish its species changing or not in the green returning stage in the spring. The previous studies also have shown that the speed of turf establishing rate mainly depends on the seeding date, seeding rate and basic lawn cutting height, while the green returning rate of the overseeding turf in the next year depends on the lawn cutting height and other factors. In this study, hybrid Bermudagrass [C. dactylon×C. transvaalensis)]328was used as the warm-season basic turf, which had been planted for three years, and the perennial Ryegrass [Lolium perenne L cv. pinnacle] was used as the overseeding cool-season turf, when autumn fall came, the perennial Ryegrass was overseeded into the hybrid Bermudagrass basic turf, and then determined the effect of nitrogen application quantity and mowing frequency on the overseeding turf in grass green returning stage in the spring of the next year. The results showed that:1. In Bermudagrass grass green returning stage, higher nitrogen application quantity and mowing frequency is more beneficial to increasing the tiller, density and the green returning speed of Bermudagrass.2. During the species changing between Bermudagrass and perennial Ryegrass, the results showed that different nitrogen application quantity and mowing frequency have little effect on the Ryegrass death rate, the death rate of the Ryegrass is obviously effected by temperature, the higher temperature in spring led to a higher death rate of the Ryegrass and a smaller density of the over-seeding turf.3. There is no significant difference in the leaf width of Ryegrass and Bermudagrass when the treatments were treated with different mowing frequency and nitrogen application quantity. But the result showed that higher mowing frequency and higher nitrogen application quantity led to a higher per unit area dry weight in Bermudagrass.The results showed that higher nitrogen application quantity and higher mowing frequency promoted the growth of Bermudagrass and accelerated species changing of the overseeding turf in spring. It so indicated that higher nitrogen application quantity and mowing frequency can accelerated the speed of the overseeding turf returning green.