David Daehnke

gardeningguru@juno.com
Mahwah, NJ
United States

Black Vine Weevil - Adults, which are broad-nosed and flightless, are active at night notching leaves. Larvae eats roots and may girdle crowns of broad-leaved evergreens, particularly rhododendrons, azaleas and yews. Look for notched leaves beginning in June. If plant has notched leaves and is wilting, look for larvae on roots. Use a foliar systemic spray when damage begins. Entomopathenogenic nematodes sprayed on the ground help to control larvae. Drenching beds with chemical to kill larvae is not effective.

Japanese Beetles - Adults feed on fruits, flowers and leaves of many plants. Larvae may seriously damage lawns and the roots of small plants. Flowers such as roses may be destroyed by large adult populations. Look for adults from late June through early August. In late summer roll back dead patches of lawn to determine the number of grubs present. Milky spore disease can be disseminated against grubs. Weekly sprays in July with bendiocarb will provide only partial adult control. Traps are counterproductive unless used over a community-wide area.

Euonymus Scale - This armored scale attacks and frequently kills most species of evergreen euonymus. Light infestations on bark cause no obvious damage. In heavy infestations, leaves are covered mostly with white male covers and develop yellow spots. Dormant oil sprays should control light bark infestations. In heavy infestations, use a systemic insecticide. Spray crawlers in May through July and August through September with horticultural oil or other insecticides. Do not spray if black lady beetles with two red spots are present. They are the good bugs!

If you have any specific IPM questions, please e-mail me at IPMQuestions@Gardeningguru.org or The Q & A Message Board to see if it has previously been asked.