Roanoke Times
Copyright (c) 1995, Landmark Communications, Inc.
DATE: SUNDAY, April 11, 1993 TAG: 9304120302
SECTION: HOMES PAGE: E1 EDITION: METRO
SOURCE: John Arbogast
DATELINE: LENGTH: Medium
BOXELDER BUGS MOSTLY JUST NUISANCES
Q: We've had a problem with insects that are about the size and shape of lightning bugs but are black with orangy-red lines on their backs. These flying insects showed up in droves last summer. Initially, I discovered them on my hosta plants, in the hundreds. Then, I noticed them on the ground (in mulch areas) and some invaded the house. Now they are back. Please tell me what these insects are, and what I can do to get rid of them. J.P., MonetaA: Sounds like boxelder bugs. They're more of a nuisance than anything. They don't hurt plants, animals, houses or anything, but they come in overwhelming numbers. The adults and immature stages of the bug feed (without causing damage) on the leaves and other parts of trees in the maple family, particularly the boxelder tree.
They spend the winter in protected places, such as under porches, in cavities in brick or stone walls, in leaf litter around shrubs and under boards and tarps around houses. As you have noticed, the bugs gather in large numbers around houses and other buildings in the spring and fall.
Spray the swarms of adults and nymphs (young stage) outdoors with liquid Sevin or malathion and, to some extent, the bark and leaves of nearby trees. Several applications may be necessary because of the normally large numbers in the swarms.
Get rid of those inside with a vacuum cleaner or broom and dust pan. Plug openings in window sashes and caulk cracks to keep the bugs out.
Q: Four years ago I set out 10 hemlocks in a row for a wind break. They're now 4 feet tall. Last year one turned yellow and died. I replaced it, and about three weeks ago I noticed another was beginning to turn yellow. What is the problem? I have the hemlocks planted near an oak tree. Please provide information on this hemlock problem. R.M.P., Blacksburg
A: Since another started to show symptoms during late winter, a time when most plant disease and insect activity in our area is at a low point, I would guess that your hemlocks are beginning to fail now because of some environmental factor on the site, such as poor drainage or soil compaction.
Here are some suggestions:
Don't try growing hemlocks directly under under an oak tree. The root systems of the two likely will compete for nutrients and moisture. A nearby oak should not be a problem.
Cut off affected branch portions and dig out part of the root system of the one that is yellowing or remove the whole plant to examine for rotting roots. Take a sample to your Montgomery County Extension Office, which is on the second floor of the Courthouse Annex at 3 Franklin St. in Christiansburg, telephone 382-5790.
Take a soil test from the area of the hemlocks and follow recommendations to fix any pH or nutrient problems identified. Also, fix any drainage problems in that area.
Q: I am buying a vacation/retirement home in Ocean City, Md. Around the foundation is a ground cover like prickly cedar through which is growing a stand of thick grass . I would like to replace it with another cover. How can I kill the existing one? Can you give me names of covers that stay green? Mrs. N.G.L., Christiansburg
A: The existing ground cover plant is probably low-growing junipers, although without seeing a plant or at least a representative sample I can't be sure. Junipers can be eliminated by digging. The grass can be killed with two treatments of the nonselective plant killer glyphosate (brand names Roundup and Kleenup) when the plants are actively growing.
If the grass that's growing around the foundation is wiregrass, you can kill it with glyphosate but you may have to use handpower later to remove shoots that may continually creep into your new ground cover.
I can't suggest plants for your home without seeing the site. Ask a landscaper or extension agent in the Ocean City area for recommendations. Even though that part of Maryland is in a plant hardiness zone just slightly milder than ours, growing conditions in addition to climate may be more important in selecting plants to do well there.
Q: I have hibiscus plants (not the shrub type) that die back each fall. When they come out in the spring, the stems get long with very few branches. Can these plants be pinched back at the ends when they get about a foot tall so they will have more branches and not get as tall? I notice that when I take the dead stems in the fall, they look hollow inside so I have hesitated on pruning them. Mrs. T.M.C., Roanoke
A: The top 2-inch stem section of your plants can be pinched out in the spring when new shoots are about 8 inches tall in order to stimulate more side branches or stalks to form. I'm assuming you're growing the plants in full sun.
Got a question about your garden, lawn, plants, or insects? Write to Dear John, c/o the Roanoke Times & World-News, P.O. Box 2491, Roanoke, Va. 24010-2491.
John Arbogast is the agriculture extension agent for Roanoke