Brown Patch Occurrence in a Zoysiagrass-Tall Fescue Polystand Compared with a Tall Fescue Monostand

Abstract

Core Ideas A polystand mixture of tall fescue and zoysiagrass showed reduced brown patch disease severity compared to a tall fescue monostand. Mixing zoysiagrass with tall fescue improved turfgrass quality during summer months when brown patch was active. In turfgrass systems, creating polystands with comparable color and texture may be a feasible strategy for reducing disease. Tall fescue (Schedonorus arundinaceus Schreb.) is used frequently in Kansas due to its heat and drought tolerance compared with other cool-season grasses. Brown patch caused by the fungus Rhizoctonia solani Kühn AG-2–2 IIIB is the main disease limiting the growth of tall fescue in summer, and brown patch resistance in tall fescue cultivars is limited. Polystands of Japanese lawngrass (Zoysia japonica Steud.), commonly referred to as zoysiagrass, and tall fescue have the potential to provide a lower-input turfgrass sward that has good autumn and early spring color. Our objective was to determine whether a polystand composed of a seeded zoysiagrass (‘Compadre’) and tall fescue (‘Corona’) would reduce brown patch severity compared with a fall fescue monostand while maintaining overall acceptable quality. Studies were established at the Rocky Ford Turfgrass Research Center in Manhattan, KS and Olathe Research Center, Olathe, KS in 2015 and conducted through summer 2017. In the split plot design, natural infection by R. solani or a fungicide-treated control was the whole plot treatment factor, and species (tall fescue monostand and the polystand mixture) were subplots. In both years at Olathe and 2016 in Manhattan, disease severity in the tall fescue monostands was consistently higher than the zoysiagrass–tall fescue polystand during July through September. Turf quality was consistently higher in the polystand compared with the monostand during peak brown patch outbreaks. Use of a zoysiagrass–tall fescue polystand is one option to reduce brown patch in transition zone lawns where the disease is common.