Actually, thinking of thrips as raining from the sky is pretty accurate and we are getting a pretty good flood in most areas. 

Many people are reporting 2-15 thrips per plant on cotton from the cotyledon stage up to the second true leaf.

These calls are pretty easy to answer. Spray if multiple thrips are present on plants with less than two true leaves. Certainly apply a foliar insecticide if the first or second true leaf has obvious signs of thrips injury… and don’t hesistate … especially if immature thrips are already present.

Clearly, we are dealing with adult migration that is overwhelming the insecticide seed treatments in many situations. Thrips must feed to be exposed to these systemic insecticides, and continual migration can lead to injury even if they are killing adults.  

It will be deciding if subsequent sprays are necessary as the seedlings begin to grow. Tolerate more thrips as plants get larger, and remember that you may see wrinkled leaves even after application, because you can’t reverse damage to tiny, developing leaves that occurred before treatment. 

There is virtually no data suggesting a third, foliar thrips application will improve yields on cotton having an insecticide seed treatment.

In cotton, the current debate is whether Radiant SC is needed, or whether we can stay with our standards (Orthene/Acephate, Bidrin or Dimethoate). Refer to last week’s article for more detail.

Radiant is the product of choice if you are dealing with western flower thrips. Use an adjuvant with Radiant! 

Most of the adult thrips I’ve observed are dark colored, almost black, indicating they are tobacco thrips, in which case all the above insecticides will work well at typical use rates.