|Sweep nets snaring lygus bugs in cotton.|
Moreover, UC IPM adds: “In contrast, late plantings, vigorous cotton, and high plant populations promote lower fruit retention and therefore thresholds will be lower. Additionally, duration of fruit retention may vary according to the cotton cultivar present in the field. The longer the fruit is retained, the longer it will be attractive to lygus bug populations. Finally, success in retaining early squares will greatly determine the final yield; therefore protecting cotton during the early square formation period (June) is critical. Protection during the early season is very complex. Factors such as low lygus bug numbers, high susceptibility of cotton, and variability in sampling require the grower to be extremely vigilant and ready to act at an instant.”
|Lygus numbers have increased in cotton fields.|
“If there is a spike by the end of the week, growers may order spraying,” Damien says. Growers should look at using reduced-risk materials.
There are two options for spray timing - during early fruiting when monitoring indicates lygus densities are low and square retention is only slightly off (5 percent), re-inspect the field again in three days if square retention continues to be slightly off normal. Use product that preserves natural enemies. When population densities of lygus are high and potential for repeated and sustained invasion, may needed quicker acting.
Here are some chemical options: There is some resistance to organophosphate, carbamate and pyrethroid insecticides. Suggested chemicals to use are Carbine, Belay,Steward, Diamond, Brigade, Baythroid or Warrior.
Damien reminds growers with alfalfa fields adjacent to their cotton to leave uncut strips of alfalfa during harvest. This will provide a habitat for lygus – which prefer to live in alfalfa than cotton – when the alfalfa is cut.
|Almond growers are concerned about mites in their orchards.|
UC IPM notes that “mites damage foliage by sucking cell contents from leaves. The damage begins with leaf stippling. Leaves can turn yellow and drop off. High numbers of mites cover tree terminals with webbing. Crop reduction and reduced vegetative tree growth shows up the year after damage occurs.”
Jenna says almond hulls are starting to split in most orchards. “If growers have not done their hull split spray yet, it’s on their agenda.”