Benny Martinez – Sales Representative, Dow AgroSciences Rio Grande Valley and Winter Garden region, Texas
“We do not learn from experience,” philosopher John Dewey said. “We learn from reflecting on experience.” As Texas cotton growers are in the midst of or nearing cotton harvest, this is an ideal time to gauge the success of the season and determine how to improve in the future. I always emphasize the importance of reflecting on what worked well over the past growing season to be ready for the next year.
Cotton Pest Pressure
Pest pressure was fairly typical this year. Aphids and leafhoppers usually begin their torment early in the season, especially if there is good moisture. This year was no exception. Growers started spraying early for the two pests. Many growers relied on Transform WG insecticide, which offers a new class of chemistry for outstanding control of the pests. In addition, Transform is easy on beneficials. In our area, the more beneficials you have, the fewer problems you will have with aphid flares. I recommend growers use ¾ to one oz/A of Transform for aphids and fleahoppers. When scouts find around 50 aphids per leaf or a 10 to 15 percent infestation rate of fleahoppers, then it is time to spray. Smaller squares to pinhead-size squares are the most affected by leafhoppers, so growers need to be scouting regularly early on. Whitefly is another pest to watch for in mid- to late season. This year, whitefly pressure was light and showed up late. I usually suggest growers spray when three to four nymphs or adults per leaf are found in the fifth leaf from the terminal. A pest unique to the coastal regions of Texas is the verde bug. Like whitefly, verde bug is a mid- to late season pest – and this year, it is showing up late. Verde bug is elusive as it flies away when humans approach, so a sweep net is the best way to check for it. I suggest spraying when four to five percent of plants are infested.
Challenges For Sorghum Growers
This year, sugarcane aphids showed up in full force in Texas, especially in the Rio Grande Valley. Some untreated fields yielded around 1,200 pounds per acre compared with treated fields that yielded 5,000 pounds per acre. In a few days, the sugarcane aphid can increase from a few pests per leaf to a few hundred per leaf. Scout at least twice per week to make timely applications. The new, effective tool this year was Transform. A majority of sorghum acres were treated at least once after the emergency Sec. 18 was issued for Transform. Work is underway to define economic thresholds, but this year, the most effective time to spray was when 30 percent of plants were infested. Many growers sprayed one oz/A in 10 to 15 gal/A of water for ground application or one oz/A in five gal/A of water for aerial application. From cotton to grain sorghum, crops in Texas have seen their fair share of pests this year. And next year will be no exception. Maintain timely scouting schedules and be prepared with spray options that work.