It’s very hot and very dry and it seems it’s only going to get hotter. Saw many fields being irrigated again this week. As we head towards harvest for sorghum and corn and eventually cotton you can really see the effect the drought has made that will correlate with significantly reduced yields and already loss in acres.
Many cotton growers were either irrigating this week or spraying their cotton with PGR or insecticide. Majority of cotton in the lower canopy has already developed medium to full sized bolls, while the later planted cotton is just barely putting on small bolls.
We still have a lot of very late planted cotton that is in full squaring mode. Pests of concern this week were cotton aphids acting up in some areas and also seeing whiteflies starting to build up in the Edinburg, Alamo, Donna, Monte Alto areas. This week I was seeing adult whiteflies but also was picking up on some whitefly nymphs/immatures. We are going to want to monitor for whitefly populations diligently and treat accordingly because growers have seen in years past (2006 with former IPM agent Manda Cattaneo) when there is a drought whitefly populations can thrive in arid conditions and reach damaging numbers.
- Whiteflies feed on the undersides of the leaves so when in your cotton fields you will want to check in various locations in the field on the undersides of leaves taken from the middle of the canopy.
- I am seeing more than 5 whiteflies per leaf in some areas and also some nymphs so we will need to use an insecticide effective for both adults and immatures or a mixture that will control both.
- Whiteflies when they feed excrete sticky honeydew like that of aphids and this is prone to attract sooty mold causing all types of growth problems for the cotton plant. Also we do not want to get closer to harvest with widespread whitefly populations so that way we can avoid a sticky cotton situation staining open bolls.
- We can keep whitefly populations down throughout the Valley as long as everyone works together to control growing populations when found.
Majority of grain sorghum is in the hard dough stage past worries from injury from rice stinkbugs or headworms. However I noticed this week in some sorghum that sugarcane aphids were building. We will continue to monitor to see if sugarcane aphids will become a problem prior to harvest and need treatment but for right now it looks good.