SALISBURY — Despite our waning growing season, Cooperative Extension still receives a number of homeowner questions via phone and e-mail. Walk-in traffic seems to increase in the late summer and early fall. The recent rains have created problems. And many problems are surfacing that are difficult to diagnose. Below are a few questions that you may have pondered.
Q: I have a large oak tree with caterpillars that are rapidly defoliating the tree. Is there anything I can do to prevent this?
A: Your problem is most likely orange striped oak caterpillars. These caterpillars appear in mid-August and early September and can literally strip a tree bare in just a few days. Since it is late summer, it will not cause any harm to the growth of the tree. However, the droppings can be a nuisance. There is no practical control for the insects.
Q: All of my irises have died. (Sample brought into the office). They turned yellow and fell over rotting at the base of the stalk. What is the problem and can I do anything to stop it?
A: Bacterial soft rot was identified on the sample. The bacteria enter the young leaves through wounds, usually made by larvae of the iris borer. The bacteria also enter through wounds caused by wind-lodge, excess fertilizer burn. A plant that has an infected rhizome should be removed and inspected to see whether any of the rhizomes can be saved and replanted.
Q: Our outdoor wooden furniture is being chewed by some type of animal. Since the chairs are near the water, my wife immediately suspected a beaver. However, I think it may be squirrels. We seem to be overrun with the pest. Can squirrels be doing this damage?
A: Yes, your problem is most likely squirrels. Add chewing wooden chairs and siding to their resume as varmints. According to N.C. Wildlife biologist Jonathan Shaw, squirrels are the most likely culprit. The incisors of rodents are continuously growing, which is an adaptation that allows them to gnaw on things and eat hard foods. These animals have an innate drive to chew on things as a result.
Q: (Sample brought in the office). The nuts on my pecan trees are have black spots on the green husks. What is this and how can I prevent this in the future?
A: Pecan scab is a major disease in our area. It is caused by a fungus that attacks both the leaves and the shuck. Application of fungicidal sprays to control this disease is not practical for homeowners because of the size and scope of mature pecan trees. Go to http://www.ces.ncsu.edu/depts/hort/hil/ag81.html for more complete information on going pecans in North Carolina.
Darrell Blackwelder is the County Extension Director with horticulture responsibilities with the North Carolina Cooperative Extension Service in Rowan County, 2727 A Old Concord Road, Salisbury, NC 28146. 704-216-8970