Application Timing of Aminocyclopyrachlor, Fluroxypyr, and Triclopyr Influences Swinecress Control in Tall Fescue

Abstract

<jats:p>Swinecress [<jats:italic>Coronopus didymus</jats:italic> (L.) Sm.] is a problematic weed in newly seeded tall fescue (<jats:italic>Festuca arundinacea</jats:italic> Schreb.) and often warrants control with herbicides. The objective of this research was to investigate the influence of application timing on efficacy of aminocyclopyrachlor, fluroxypyr, and triclopyr for swinecress control compared with dichlorophenoxyacetic acid (2,4-D) + 3,6-dichloro-o-anisic acid (dicamba) + methylchlorophenoxypropionic acid (MCPP). Aminocyclopyrachlor at 0.05 and 0.10 kg a.i./ha provided less than 35% control from February applications, but both rates averaged greater than 90% control with April applications. Fluroxypyr at 0.26 and 0.52 kg a.i./ha provided poor (less than 70%) control from February applications but control increased to 71% and 90% from April treatments, respectively. Triclopyr at 0.56 and 1.12 kg a.i./ha provided greater than 90% swinecress control at both application timings and was comparable to 2,4-D + dicamba + MCPP. Overall, aminocyclopyrachlor and fluroxypyr were only effective for controlling swinecress in April, whereas triclopyr provided excellent control with February and April applications.</jats:p>

Creeping Bentgrass, Perennial Ryegrass, and Tall Fescue Tolerance to Topramezone During Establishment

“…99% control from 12 to 20 WAS. These levels of lesser swinecress control are similar to previous reports with POST applications of synthetic auxins in established tall fescue (Reed and McCullough 2012).…”

Control of Lesser Swinecress in Creeping Bentgrass Putting Greens

“…This is similar to results of the same herbicide mixture (1.11 + 0.12 + 0.30 kg ai/ha) in tall fescue (3). The increase in control observed by Reed and McCullough (3) may be attributed to higher herbicide application rates. Sulfentrazone resulted in 22% control, while carfentrazone was ineffective 4 WAIT.…”

“…Single and sequential applications of MCPP + 2,4‐D + dicamba resulted in 91% and 99% control, respectively. Similarly, Reed and McCullough (3) observed 100% control 8 WAT in response to a single 2,4‐D + dicamba + MCPP (1.11 + 0.12 + 0.30 kg ai/ha) application. Control with single and sequential applications of sulfentrazone was 14% and 31% respectively, 10 WAIT.…”

Crystal structure of fluroxypyr

“…The efficacy of this herbicide may be affected by environmental conditions including the relative humidity, temperature and soil moisture. Because of this, its application often provides inconsistent broad-leaf weed control in winter or early spring (Reed & McCullough, 2012). Until now, its crystal structure had not been reported and we describe it herein.…”