Translator Disclaimer
1 July 2008 Effect of Simulated Rainfall on Tall Fescue (Lolium Arundinaceum) Control with Glyphosate
Travis W. Gannon, Fred H. Yelverton
Author Affiliations +

Field experiments were conducted to determine the effect of simulated rainfall after glyphosate application on tall fescue control. Three glyphosate formulations, three simulated rainfall amounts, two application rates, and three rain-free periods were evaluated. Glyphosate formulations evaluated included Roundup Original®, Roundup Pro®, and Roundup ProDry®. Herbicide drying periods, or rain-free intervals, included 15, 30, or 60 min. Simulated rainfall amounts were 0, 0.25, or 0.64 cm. Application rates of glyphosate were 3.4 or 6.7 kg ae/ha. Averaged across glyphosate formulation and simulated rainfall amount, excellent (≥ 90%) tall fescue control was observed when no simulated rainfall occurred within 60 min after application, whereas good (≥ 80%) tall fescue control was observed when 30 rain-free min were provided. Although current glyphosate labels are vague about rainfastness, these data indicate that critical rain-free periods may be as short as 30 min when higher application rates are used.

Nomenclature: glyphosate; tall fescue, Lolium arundinaceum (Schreb.) S.J. Darbyshire FESAR ‘Kentucky 31’, ‘Southern Gold’

Travis W. Gannon and Fred H. Yelverton "Effect of Simulated Rainfall on Tall Fescue (Lolium Arundinaceum) Control with Glyphosate," Weed Technology 22(3), 553-557, (1 July 2008).
Received: 2 November 2007; Accepted: 1 May 2008; Published: 1 July 2008

Get copyright permission
Back to Top