Conversion of ‘Tifway’ Bermudagrass Stands to ‘Zorro’ Zoysiagrass Turf using Combinations of Dazomet and EPTC

Abstract

Field experiments were conducted to evaluate the efficacy of herbicides and soil sterilants for the fairway conversion of ‘Tifway’ bermudagrass to ‘Zorro’ zoysiagrass. Treatments included glyphosate (4.48 kg ae ha−1), EPTC (7.84 kg ai ha−1), dazomet (338 kg ai ha−1), siduron (13.4 kg ai ha−1), glyphosate plus ETPC (4.48 + 7.84 kg ha−1), glyphosate plus dazomet (4.48 + 338 kg ha−1), EPTC plus siduron (7.84 + 13.4 kg ha−1), and dazomet plus siduron (338 + 13.4 kg ha−1). Glyphosate treatments were applied 5 wk prior to establishment (WPE), dazomet and EPTC treatments were applied 3 WPE, and siduron was applied at establishment. Dazomet and EPTC treatments were incorporated to a depth of 10 to 15 cm with a rotary tiller and rolled with a weighted roller to reduce losses from volatilization after application. Zorro zoysiagrass was established in June 2008 and 2009 using a mixture of rhizomes and stolons at a rate of 76 cm3m−2. Results indicate that glyphosate + dazomet, glyphosate + EPTC, dazomet + siduron, and EPTC + siduron were equally effective at controlling Tifway bermudagrass. EPTC and dazomet controlled bermudagrass more effectively when used in combination with glyphosate or siduron. There were no significant differences in bermudagrass cover between the EPTC combinations with glyphosate or siduron and dazomet applied with glyphosate or siduron. Comparing EPTC- and dazomet-alone, EPTC yielded less bermudagrass cover (32%) than dazomet (71%). At present, research is limited on using EPTC for controlling perennial grasses in turfgrass systems. Data from these studies demonstrate the potential use of EPTC as a preplant soil herbicide to control hybrid bermudagrass during zoysiagrass renovation.