Hello Frank,

Those are boxelder bug nymphs, Leptocoris trivittatus (Hemiptera: Rhopalidae).

Boxelder bugs nymphs are bright red in color and are quite nomadic this time of year. During the summer they feed on the flowers and seedpods of female boxelder trees and to a lesser degree on silver maple and other trees and shrubs.

Boxelder bugs invade our homes and other structures in the fall of the year looking for dry, protected sites in which to spend the winter. It is not necessary to control boxelder bug nymphs this early in the summer to keep them from invading homes in the fall. These are just the first generation nymphs. They will mature into adults and lay eggs in July. These eggs develop into the second generation adults that invade our homes in October.

Their numbers can be temporary reduced by spraying a persistent insecticide in areas where the nymphs are seen in high numbers. Products such as permethrin (sold under a variety of brand names), cyfluthrin (sold as BioAdvanced Vegetable and Garden Spray) or bifenthrin (sold as Ortho Bug-B-Gon or Home Defense Max) can be used to reduce their numbers. Be sure to read and follow all directions on the pesticide label.

Regards,

Howard

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