As long as weather is wet, peculiar problems persist

Published 12:00 am Friday, July 12, 2013

SALISBURY — We’ve learned to expect weather in July to be hot with high humidity.
However, coping with the rainy, cooler weather often compounds problems caused by insects and diseases. Below are questions posed by local gardeners.
Question: All of a sudden I have green June beetles swarming all over my yard. What can I do to control them?
Answer: The recent downpours have loosened the soil and the adults are emerging right on schedule. Controlling the adults at this time is impractical. Controlling the larvae in the fall and spring is the best way to go. Effective control of the beetle larvae is mid-August until early September. Use a granular insecticide designed to kill soil insects and grubs.
Question: I have a birch tree that has limbs that get in the way when I mow. Can I prune them now?
Answer: Yes, birch trees can be pruned without damage in late summer and early fall. Light, judicious pruning generally does not kill established trees. Birch and maples tend to be “bleeders.” Pruning them in late summer or early fall, rather than late winter or early spring with the leaves on them, is best to prevent excessive bleeding.
Question: I often see this tree with huge leaves growing around Salisbury. What is this tree?
Answer: It is most likely a catalpa tree. It grows extremely fast and can become weed-like if out of place. It’s often called “fish bait tree” because of the huge numbers of caterpillars on the tree that are often used for fish bait in the late summer and fall. Go to http://www.ces.ncsu.edu/depts/hort/consumer/factsheets/trees-new/catalpa_speciosa.html for more detailed information.
Question: I have small worms crawling all over my house. They were very bad last year and are back again this year. What can I do to control them?
Answer: Sounds like what you are experiencing is millipedes. When the weather turns hot, they become a problem. There are a number of controls. Using pesticides is a temporary control. Controlling moisture around the home may help. More complete information on the web site http://www.ces.ncsu.edu/depts/ent/notes/Urban/millipedes.htm may help.
Question: My crape myrtle has white substance on the leaves. What is this and how do I control it?
Answer: The problem is powdery mildew. It is caused by a fungus. If feasible, use a fungicide labeled for the disease. Larger trees may be impractical to spray for the disease.

Darrell Blackwelder is the County Extension director with horticulture responsibilities with the North Carolina Cooperative Extension Service in Rowan County.