Here’s some recent info on the efficacy of various insecticides for stonefruit.
Click on the link to view the table. The higher the number, the more efficacious the insecticide for that particular insect.
I thought it was interesting, they only give two insecticides their top rating (i.e. 4) for controlling PC. Imidan and Exirel.
I looked into Exirel once because it’s supposed to be very effective on a lot of insect pests. The price was scary expensive. As I recall the price was over $1000/gal. The rep told me it was the only real tool citrus growers in Florida had for controlling Asian citrus psyllid, the carrier of HLB. Because of that Dupont was charging ransom prices.
It looks like the price has come down some. I googled it just for kicks, and here’s a bottle on Ebay.
Malathion is just about as good and a heck of a lot cheaper. If you
read the fine print as to how this person arrived at her rating system,
there’s too much subjectivity involved.
Similar to Imidan, it is not for residential use, according to the label.
It is incredibly expensive when you see how much is required per acre- 13.5 to 20.5 fluid ounces!
It may knock down those in the trees when you spray, but it loses its potency very quickly and has never been considered a useful pesticide for PC control, at least with commercial growers. Guidelines convinced me not to even experiment with it except for aphid control, so I can’t say I’m speaking from experience.