Grower attention to preservation of beneficial species can contribute to this natural control. The cool temperatures this summer are also helping to keep mites down. Fewer generations means slower mite population increase and more time for mites to get eaten by a predator or succumbing to a fungal disease before reproducing. Dogwood borers are now at peak laying activity. The threat of RAB infestation is greatest on border row trees within 100 meters of surrounding forest.
Dogwood borers prefer burr knots.
Insecticide application targeted against apple maggot will control the adult females before they can lay eggs. Trees with trunk diameter of less than 4 inches are more susceptible to damage. If there is a history of borer damage, trunk application of Lorsban 50WP is the most effective control option. Thiodan is a second option, but will require two applications about a month apart to achieve equivalent protection. Spotted tentiform and Apple blotch Leafminers Second generation leafminer mines should begin appearing any day now in the Sanford area, and around July 23 in the Highmoor Farm area.