David Daehnke

gardeningguru@juno.com
Mahwah, NJ
United States

Dogwood Anthracnose - Check lower branches for dead twigs. Dead leaves from the previous growing season may be attached. Prune and destroy dead twigs and branches. When the weather is cool and wet the spores are splashed onto young twigs and leaves causing brown spots. Apply fungicide during bud break to protect new flowers, twigs and foliage. Further applications may be needed if weather remains cool and wet.

Euonymus Scale - Fertilized adult females have black oyster-shell shaped 1/8 inch long scale covers. These can be found over wintering on bark. Horticultural oil treatments are effective for light infestations.

Pine Sawflies - Look for rows of yellow spots in needles indicating the presence of eggs. With light infestations on small pines, handpick and destroy. With heavy infestations, use horticultural oil. Later, check for half eaten needles indicating the presence of larvae, and spray with oil. Stressed plants may attract sawflies, so improving cultural conditions will help.

Hemlock Woolly Adelgid - The females, covered in a fluffy white wax, are producing eggs found at the base of hemlock needles. Apply dormant oil in March/April. There are two generations a year, so a second application may be needed in September.

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.