Crop Update Over the past several days, the summer weather arrived with a vengeance. Based on Mesonet data, August 1st had the highest single day in 2016 for evapotranspiration (ET) for cotton planted May 15th. The Mesonet Irrigation Planner indicated August 1st had 0.36”, 0.48”, and 0.42” at Altus, Tipton, and Hollis, respectively.
With all irrigated cotton blooming, we are now at peak water use for the crop. For the past week, ET at Altus totaled 1.85”, 2.27” at Tipton, and 2.13” at Hollis. Dryland cotton in many areas is holding up very well, but other areas that were shorted with rainfall during July are hitting high stress at this time.
Some dryland fields came into bloom at 9 nodes above white flower, which indicates outstanding yield potential. This also indicates that we have sizeable plants out there. This large biomass comes with a high moisture requirement. Hopefully we will get some badly needed precipitation across the area to keep the dryland crop moving in the right direction. It appears that we have somewhere around 278,000 acres planted in 2016 based on Oklahoma Boll Weevil Eradication Organization data. This is up nearly 30% from our 215,000 acres planted.
Insect Update
Reports are being received that an outbreak of stinkbugs occurred two weeks ago in a large number of fields. Jackson County cotton traditionally has low stink bug populations, and stink bugs usually don’t have widespread migration in the area. This coincides with Bacterial blight being observed in numerous fields. Bacterial blight symptoms could potentially be confused with stink bug damage on bolls unless properly examined. It is important to understand the differences in these maladies.
Stink bug feeding results in carpel wall punctures, whereas lesions from Bacterial blight infections initiate on the outer surface of the carpel wall. Suspected stink bug damaged bolls should be opened and closely examined for wart-like growths on the interior of the carpel wall (see photo above).
A poorly timed disruptive spray could cause the unnecessary elimination of beneficial arthropods. This disruption in beneficials could cause a later outbreak of aphids and/or spider mites. Weekly scouting should continue for all pests as the crop has now moved into the boll production stage. Moth counts continue to be below the long-term exception of the Beet armyworm pheromone trap at Tipton.
