Whiteflies hit the threshold on the UGA Bowen and Tifton Campus farms this week. I know of a few people who have started spraying for them, but keep in mind that they are starting to build up, so be on the lookout for them. Keep in mind, SLWF Threshold: Treat when 50 percent of sampled leaves (sample 5th expanded leaf below the terminal) are infested with multiple immatures (≥5 per leaf). Hairy leaf cotton and dryland fields will probably be impacted the most. The forecast for next week is ripe for areolate mildew and target spot. Priaxor, Miravis Top, and Headline are “go-to products” for target spot, while Priaxor and Miravis Top are best for areolate mildew. I haven’t seen much of either here in Tift, but it’s probably lurking out there somewhere. I’m getting a lot of calls on cotton leaf roll dwarf virus (CLRDV); if you have plants that are reddening and crashing, let me know. Some I’ve seen have just been potassium deficiency, but the virus has been rearing its head this year. Speaking of low potassium, potassium nitrate is the most common material used for foliar K applications. If you’re showing potassium deficiency (See image below), 1-2 foliar applications of 5-10 lbs/K2O may be needed. Based on field research trials, foliar fertilization is most effective when applied during peak bloom or the first 4 weeks of bloom. Foliar feeding during the 5th – 7th week of bloom may or may not be effective depending on the particular cotton variety grown. Once you pass the 8th week of bloom, it is too late, and no foliar feeding is recommended.
