David Daehnke

gardeningguru@juno.com
Mahwah, NJ
United States

Azalea Bark Scale - In May/June look for sooty mold on leaves and yellowing leaves. Also look for white egg sacs in twig forks and for reddish crawlers that settle on twigs in June and July. Use a summer oil spray in July after crawlers are out of the egg sacs.

Pine Sawflies (Pines and other conifers) - In early May look for rows of yellow spots in needles indicating the presence of eggs. If a light infestation occurs on small pines, hand pick and destroy. If needles are yellow, curled or half-eaten, look for clusters of larvae near defoliated twigs and branches. Use horticultural oil or systemic insecticide for control.

Pine Spittlebug - This native spittlebug prefers Scotch pine, but also attacks many other pines. Look for spittle on twigs in May and June. Check again in July and August for adults feeding without spittle. In light infestations on small pines, remove manually. Heavy infestations may kill Scotch pines. Spray with a residual insecticide in May.

Lace Bugs (Azalea, Rhododendron, Andromeda) - In early May look for signs of newly stippled leaves and black fecal spots on undersides of leaves. Horticultural oil and contact insecticides will give control only if lower sides of leaves are sprayed. Systemic insecticides will give excellent control.

Hemlock Woolly Adelgid - Look for fluffy, white wax on twigs from March through June and again in late summer into fall. Use dormant oil from November to early March. Use foliar oil or horticultural soap sprays from July through October to kill immature adelgids.

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.