Bermudagrass Recovery From Scalping Injury in Shade.

Bermudagrass is the most widely used warm season grass in the southern United States because of its good resistance to drought, heat, disease and insect damage. However, bermudagrass does not tolerate shade very well. Recently the OSU turfgrass breeding team developed two new bermudagrass varieties, Latitude 36 and NorthBridge that establish quicker and recover faster from many stresses. However, bermudagrass with a faster growth rate tends to have more thatch accumulation which promotes scalping injury. It is commonly believed that the high shoot to root growth ratio common in shade makes grass more susceptible to scalping. Even though bermudagrass tolerates scalping well, shade following scalping may delay its recovery after the injury or eventually kill the plant. The objective of this study was to evaluate the recovery rates of bermudagrass cultivars from scalping injury in shade. Plots (2.3 m x 2.3 m) with 0.23 m borders were established by sod with 10 replications of four bermudagrass cultivars, Tifway, Northbridge, Latitude36, and OKC70-18 in a completely randomized design in 2008. The plots were maintained as a typical golf course fairway at a mowing height of 1.3 cm. Three light treatments; full sun, 31% shade, and 63% shade, were randomly assigned to three replicates of each cultivar. Different plots were assigned for each experiment. Portable shade structures (0.3 m height) made of polyvinyl chloride (PVC) pipes covered with black woven shade cloth were placed shade plots for four weeks before scalping. Visual quality (VQ) and NDVI were collected weekly following scalping to evaluate the recovery rates of bermudagrass from scalping injury. Data was collected from 11 June to 6 Aug (summer) and 14 Aug to 15 Oct (fall) in 2012. There was no significant difference found in VQ among cultivars in full sun. However, Latitude36 had higher VQ than OKC70-18 and Tifway at 2 weeks after scalping (WAS) in 63% shade and 1 WAS in 31% shade. In full sun there were no significant differences in NDVI except at 3 WAS when Latitude 36 exhibited faster recovery from scalping than Tifway. Also, NDVI indicated that Latitude36 recovered faster than Tifway in both 31% and 63% shade at 2 WAS, but the cultivar did not differ at the end of the rating period.