Current Crop and Pest Situation

Kerry Siders is Texas A&M AgriLife Extension Agent-IPM for Hockley, Cochran and Lamb Counties. A Texas Tech graduate, he has been with Texas AgriLife Extension since 1990, providing education and applied research for weeds, insects, diseases, nematodes, growth regulators and harvest aids in cotton. He is a member of the High Plains Association of Crop Consultants.

“Not much has changed over the last couple of weeks in cotton other than the physiological state of the cotton itself. However, I would still not let your guard down for a while longer, especially in cotton which has late growth, non-Bt cotton, or may have excessive nitrogen levels. Some fields – the earliest planted – are at the point of maturity that most insects are of no consequence.

“Most cotton will need to be monitored for at least another 10 days, maybe through the first week in September for later cotton. Cotton is generally safe from most pests when approximately 400 heat units (about 20 days) past the 5 nodes above white flower have accumulated. Cotton aphids would be one insect which could develop up through boll opening. I doubt if this will be the case this year, as no cotton aphids have been found in area fields.

“Cotton irrigation is still very critical with very limited rain showers. Cotton is still using anywhere from 0.15” to 0.25” per day. This is down from near 0.30” per day at the peak just a few weeks ago. Evapotranspiration has decreased considerably with mid-90s temperatures and decreasing day length.

“Weeds continue to be a concern for many. Be careful in your enthusiasm to kill these weeds. First, ask if these weeds are just cosmetic at this point or will their seed production haunt you in the future (i.e. morningglory, marestail) or cause you harvest problems. I am seeing many fields with large pigweed being hoed. I applaud your effort, albeit costly. But most likely, those weeds represent a real hurdle to harvest. For young flushes of weeds, however, control may not be necessary. In some situations, you might just save money for a good harvest aid program and be prepared to do a much better job next year with residual herbicides.”