This week (June 8) we were feeling the heat with temperatures right at 98, 99, or 100oF with a heat index making it feel like 105oF most days. Yesterday we received a random rain spell in Bayview that gave 1 inch of rain but rest of the Valley remains dry and untouched by rain water.
According to the Texas Boll weevil Eradication program we currently have 213,159.6 acres that have been planted into cotton this year. However there are approximately 25,000 of those acres already destroyed due to poor stand, majority being dryland acreage. To date they have trapped/captured 1,149 weevils. They have treated a total of 123,813.5 acres to date for boll weevils. This includes Fixed Wing,
Helicopter, Hi-Cycle and Mist Blower applications to control the boll weevil. Edward Herrera, Zone manager for the LRGV Texas Boll Weevil Eradication program shared with us that the majority of acreage treated are adjacent to the Rio Grande with thousands of acres on the northern to eastern part of the LRGV zone with zero applications. The Texas Boll Weevil Eradication in cooperation with our Valley cotton growers continues to make great strides in effort to control boll weevil that not only affects our area but the rest of the U.S. cotton production as well.
Pests on our radar in cotton this week are tarnished plantbugs, Verde bugs and whiteflies.
With applications of glyphosate going out on sorghum ready to be harvested it seems that tarnished plantbugs are moving out of the grain and into the cotton which is not good for those smaller, immature sized bolls. I noticed this taking place along Military HWY in the Donna area. We also picked up on tarnished plantbugs in the Rio Hondo area that migrated out of sesame into the adjacent cotton field. Basically if you have cotton near a grain sorghum or sesame field now is the time to go check for tarnished plantbugs that could have possibly migrated out of those fields to feed on the immature tender bolls and also large squares in cotton.
Tarnished Plantbug and Verde Bug
Tarnished plant bugs have piercing sucking mouth parts. Adult tarnished plant bugs are mainly brown in color mottled with red yellow and black and have wings. Nymphs are similar to the adults but they lack wings and are greenish in color with black spots. Females lay whitish eggs inserted into the host plant and hatch in about 8 days. From egg to adult the tarnished plant bug life cycle is about 3 to 4 weeks and produce 5 generations a year.
Thresholds in blooming cotton for tarnished plant bug are 10 to 15 tarnished plant bugs per 100 sweeps. So if you guys are seeing 1 to 2 adult tarnished plant bugs per 10 sweeps and noticing some nymph activity this warrants a spray treatment. Access your cotton field to see if you have more immature bolls than mature as once bolls are larger than 1 inch diameter and cannot be squeezed open they are generally safe from plant bug damage.
Same goes for Verde bug being seen in the Rio Hondo and Bayview areas as they will pierce immature bolls and squares with their mouth parts causing boll malformation to complete fruit loss. Verde plant bug adults are about ¼ inch long in size and are light green in color with long antennae and red eyes. cotton along the river off Military HWY from Progresso to the Pharr area where we are starting to see some light sooty mold in the lower portion of the canopies. Be mindful that both adult and nymph whitefly populations are present when deciding on a spray treatment.
As we gear up to harvest please be mindful of late sugarcane aphid populations that could potentially get out of hand and cause leaves to get sticky with honey dew. We want to avoid any issues with combines
breaking down due to the stickiness the sugarcane aphids can cause when they excrete the honey dew. While the majority of the valley has been incredibly clean when it comes to sugarcane aphid populations there are still some areas where they are present and increasing quickly with the current heat. So please look at your fields and see if treatment will be necessary prior to harvest.