Ocassionally, flower thrips can be an early season pest of peach and nectarine, especially when conditions during bloom are hot and dry. That seems to be the case this season as 6 out of 7 nectarine blocks scouted in Gloucester County had low populations of thrips present. At least one block had low levels of injury present. Mostly adults were found but examinations of fruitlets found some nymphs present in the shucks. If left untreated, damage can occur unless conditions turn cool and wet. Growers can scout for thrips using beating trays to look for adults, or by collecting blossoms to look for nymphs feeding inside the shucks. Peach may be less susceptible to damage than nectarine because the fuzz acts as a deterrent. Growers should also look for aphid populations while scouting for thrips as aphids are just starting to appear in southern county orchards. Use a treatment threshold of 1 aphid colony per tree in nectarines and 2-4 colonies per tree in peach.

There aren’t many choices for thrips control in Nectarines.  Delegate and Entrust at the high rates are very effective.  Where aphids are also present, the neonicitinoids Actara and Closer will control aphids but may only suppress thrips. Lannate SP has a good rating for thrips and aphids in our production guide but field experience is variable. Carzol is no longer labeled for Peach and Nectarine.

Remember also that Oriental Fruit Moth, Plum Curculio, and native plant bugs are key pests at this timing so any insecticides applied for thrips and/or aphids will be in addition to applications of effective materials for these important pests.

The Cougar Blight model over at NEWA is predicting a high risk of fire blight for this coming week, due to the coming hot weather and high humidity along with a chance of showers.

Currently May 5-9 looks like a high risk period for infection. Growers should apply antibiotic to any apple or pear blocks with open blossoms prior to any risk of infection. Streptomycin and oxytetracycline formulations are generally thought to provide 1-2 days protection and possible 24 hours back action. A predication of high risk over a 4 day period may require 2 applications 2 days apart, especially if there is rainfall, and/or the orchard is not yet at full bloom. Follow the label rates. 24 ozs. of strep/acre should suffice. Check your local conditions using NEWA and check back daily as the prediction may change.