Preemergence Herbicide Effects on Establishment and Tensile Strength of Sprigged Hybrid Bermudagrass

Core Ideas Preemergence herbicides may increase grow‐in time for hybrid bermudagrass sprigs. Preemergence herbicide treatments did not reduce sod tensile strength. Preemergence herbicides are viable options for weed control during establishment. Preemergence herbicides often negatively affect establishment of sprigged hybrid bermudagrass (Cynodon dactylon (L.) Pers. × C. transvaalensis Burtt‐Davy). However, limited research has quantified the effects of preemergence herbicides on establishment and tensile strength of warm‐season turfgrass species commonly grown as sod in the southeastern United States. Field research was conducted at Mississippi State University in 2016 and 2017 to evaluate the effects of atrazine, atrazine + S‐metolachlor, dithiopyr, flumioxazin, indaziflam, liquid‐ and granular‐applied oxadiazon, S‐metolachlor, pendimethalin, prodiamine, and simazine on grow‐in time and tensile strength of newly sprigged ‘Latitude 36’ hybrid bermudagrass. Plots (4.65 m2) were sprigged at a rate of 44 m3 ha−1 (468 US bushels ac−1), and preemergence herbicide treatments were applied at the recommended labeled rates 1 d after planting. Dithiopyr, flumioxazin, S‐metolachlor, and indaziflam increased days to reach 50% hybrid bermudagrass cover in both 2016 and 2017. Normalized difference vegetative index and relative chlorophyll index were similarly affected. No herbicide treatments reduced sod tensile strength in either year; however, prodiamine, pendimethalin, dithiopyr, flumioxazin, and S‐metolachlor unexpectedly increased sod tensile strength in 2017.