Blackwelder column: Answers to gardening questions

Published 12:00 am Friday, September 14, 2012

SALISBURY – Cooler weather is a welcome break, hinting a change in seasons is imminent. Now is the time to consider a number of outdoor chores, including lawn renovation, last-minute pruning, dividing perennials and other gardening chores. Below are a few questions that Cooperative Extension has received over the past few days.
Q: I was doing some light pruning on my beech tree this past weekend and I found one limb coated with a white substance that looked at first like a fungus. Upon further inspection, I discovered it was a large mass of white, sticky, wiggling insects. What is this insect and how do I control it?
A: According to David Stephen, N.C. State University entomologist, the mass is an insect known as the beech blight aphid, Fagiphagus imbricator, one of our most interesting and recognizable aphids. They begin to show up on branches of beech in mid-summer, forming compact masses containing hundreds of aphids. The insect is a close relative of woolly alder aphid, which gets on silver maples in late spring or early summer before moving back to alder. Despite being so conspicuous, they don’t seem to cause noticeable damage to beech, and controls aren’t warranted.
Q: My neighbors have a really cool planting at their mailbox. It has thick succulent green leaves during the summer but is blooming now with pink heads. The blooms really attract the butterflies and bumblebees. What is plant?
A: The plant is sedum Autumn Joy. It’s a member of the Crassulaceae family which contains around 400 species of leaf succulents varying from upright plants to low lying, creeping groundcovers. The flowers open in late summer which is attractive to butterflies and bees; in winter, browned flower heads are considered ornamental. Local garden centers will have this hardy perennial. Go to http://www.ces.ncsu.edu/depts/hort/consumer/factsheets/perennials/Sedum’A.htm for more detailed information.
Q: There is the yellow flowering weed found in pastures and along the roadsides. It usually blooms in the late summer and smells very strong. What is this weed and how do you control it?
A: It sounds much like common sneezeweed, or bitterweed. The plant grows in moist low areas, usually in open habitats, throughout the state. The plant is actually considered poisonous, especially to sheep, cattle and especially horses. Applications of post-emergence herbicide blends should keep the weeds in check.
Darrell Blackwelder is the county extension director with horticulture responsibilities with the North Carolina Cooperative Extension Service in Rowan County.