Adding a late fall application of Proxy (ethephon) before two traditional spring applications improves seedhead control of annual bluegrass

Authors

Zachary Reicher, Bayer Environmental ScienceFollow
Matthew Sousek, University of Nebraska-LincolnFollow
Aaron J. Patton, Purdue UniversityFollow
Adam Van Dyke, Professional Turfgrass Solutions
William C. Kreuser, University of Nebraska-Lincoln
John C. Inguagiato, University of Connecticut - StorrsFollow
Kevin M. Miele, University of Connecticut - Storrs
John Brewer, Virginia Tech University
Shawn D. Askew, Virginia Tech UniversityFollow
Aaron Hathaway, Nufarm Americas Inc., Howell, MI
Thomas A. Nikolai, Michigan State UniversityFollow
Alec Kowalewski, Oregon State University
Brian McDonald, Oregon State UniversityFollow

ORCID IDs

Zachary J. Reicher https://orcid.org/0000-0002-7396-712X

Aaron J. Patton https://orcid.org/0000-0003-3870-7709

Adam Van Dyke https://orcid.org/0000-0002-3016-4570

Alec Kowalewski https://orcid.org/0000-0002-2854-3483

Date of this Version

2020

Citation

Crop Forage & Turfgrass Mgmt. 2020;6:e20031.

https://doi.org/10.1002/cft2.20031

Comments

This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License.

Abstract

Annual bluegrass (ABG) (Poa annua L.) is a prolific seed producer in the spring on golf courses that in turn decreases aesthetic quality and trueness of ball roll on coolseason putting greens. Proxy (ethephon) applied twice in the spring after green-up is the current industry standard after the loss of Embark (mefluidide) from the turf and ornamental market. However, plant growth regulators including Proxy have been used for years to help suppressABGseedheads with inconsistent success. The primary objective of this study was to determine if ABG seedhead suppression is improved by adding a late fall application of Proxy to the two traditional spring applications of plant growth regulators at nine locations with diverse environments.Asecond objectivewas to determine the importance of including Primo Maxx (trinexapac-ethyl) in fall and spring applications. Adding a late fall application of Proxy prior to the two spring applications (F+S+S) improved control of ABG seedheads over the traditional two spring applications (S+S), but themagnitude of improvement varied among locations. When treatments were applied F+S+S, the industry standard tank mixture of Proxy + Primo Maxx provided consistent ABG seedhead control and turf quality, similar to Proxy + Fiata (phosphonate + proprietary pigment) and equal to or better than Proxy alone.