Bagworms in the “dunce cap” stage. B. t. and Conserve provide good control at this stage.
Bagworm infestation with bags already drooping down.
Damage from bagworm feeding (Photo by: T. Simms).
Bag with green foliage incorporated into it suggests a live caterpillar inside the bag. Insect growth regulators (Dimilin or Confirm), Acelepryn, Conserve (depending on bag/caterpillar size and population density) pyrethroids, acephate or carbaryl provide good control against larger caterpillars. Caterpillar feeding is usually finished by mid-August, consequently hand picking in September – May is a good method to reduce next season’s populations. Photos provided by: Brian Kunkel, University of Delaware
Aphids are feeding and reproducing on many plants at this time of the year. The picture is of aphids feeding on tulip popular. Honeydew falling onto furniture, structures, vehicles, other plants and walkways can be a nuisance issue. These usually require no control efforts.
Some bagworm eggs have hatched and larvae have ballooned to nearby hosts. Look closely for the ‘dunce cap’ stage of these caterpillars feeding on trees and shrubs. Applications of Bt now through late June will provide excellent control of these small caterpillars.
Pine spittle bug requires no control efforts. They are just unsightly.
Roseslug sawflies are feeding on roses at this time. Early instars cause ‘window paning’ damage to leaves. Eventually the remaining dermal tissue of the leaf dries out and falls off the leaf leaving behind a smooth-edged hole in the leaf.
Sweet Mockorgange is in bloom to full bloom in Sussex county. As the sign indicates (from the education gardens) the arborvitae leafminer adult is flying and tussock moth caterpillars are feeding.
All pictures provided by Tracy Wooten, University of Delaware
Horsechestnut leaf blotch. Photo from: Bob Mulrooney, University of Delaware.
Photos for brown patch, roseslug sawflies (search roseslug sawfly), bagworms and fall webworms (Insect Hotline Issue 20, 2008 has best images) have already been posted. Please use search function to locate images.
Images of bagworms have been uploaded to the website in the past. Please use the search function to locate these photos.
Bagworm feeding on hawthorn. Photo taken by: Brian Kunkel, Ornamentals IPM Specialist, University of Delaware
Bagworms feeding on Leyland cypress. Photo taken by: Brian Kunkel, Ornamentals IPM Specialist, University of Delaware