Problem Identifier Unit Screen//v.w/ RR Template Plum Curculio


Problem
The ripening fruit is misshapen, rotten, and often drops prematurely. There are holes about 1/8 inch in diameter and deep, crescent-shaped scars on the fruit. When cut open, the damaged fruit may contain crescent-shaped yellow-gray grubs with brown heads.

Analysis
(Conotrachelus nenuphar)

These insects, found east of the Rockies, attack other stone fruits, apples, and pears, as well as apricots. The adult insects are brown beetles with long curved snouts. They hibernate in debris and other protected places during the winter. The beetles emerge in the spring when new growth starts and begin feeding on young leaves, blossoms, and developing fruit. After 5 to 6 weeks, the female beetles start to lay eggs in the young fruit. The grubs that hatch from the eggs feed for several weeks in the fruit. Usually the infested apricots drop to the ground. The grubs eventually leave the fruit and bore into the soil, where they pupate. The emerging beetles feed on fruit for a few weeks, then go into hibernation. Or, in the South, they will lay eggs, producing a second generation of grubs in the late summer.

Solution
Once the fruit is infested, there is no way to kill the grubs inside the fruit. Spray with an insecticide containing malathion to kill beetles that may be feeding on fruit, or laying eggs. Pick up and destroy all fallen fruit. Next spring, spray the trees when the petals are falling from the blossoms; repeat applications according to directions on the label.


Related Links
Plant Care for Apricot
Insecticides
Weevils


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