As we move into that time of year where cotton stalk destruction becomes a main focus for cotton growers, I wanted to share some great information from Danielle Sekula, IPM Extension Agent. She worked with Dr. Josh McGinty, Extension Agronomist, to conduct herbicide stalk destruction trials in the LRGV to investigate which herbicides provide good control of cotton stalks, rendering them non-hostable for boll weevils.
Please click here to view two herbicide stalk destruction trials from the LRGV for 2018 and 2019, as well as the trial conducted at the Corpus Christi AgriLife Research & Extension Center in 2019.
Danielle Sekula provides the following summary in Issue 18 of her Pest Cast Newsletter:
In the attached report you will see in the graphs that in both years, the use of Duplosan at the full rate proved to be effective at controlling cotton in all cultivars. In both years, the addition of thidiazuron (Dropp or Freefall) improved efficacy of both dichlorprop (Duplosan) and dicamba (Engenia). In both years it was noted that when slight regrowth (leaves approximately 1-1.5” across) is present, both dichlorprop and dicamba work fine. When more regrowth and larger leaves were present, control was reduced. Smaller regrowth=better control, however control of stalks with zero regrowth has been inconsistent. Freefall currently has a 24(c) Special Local Need registration in TX for post-harvest control of cotton (SLN # TX 200004, valid through December 31, 2025). The 24(c) label for Freefall can be found at:http://www.cdms.net/ldat/ld9P0004.pdf
