ROANOKE TIMES
Copyright (c) 1996, Roanoke Times
DATE: Sunday, July 14, 1996 TAG: 9607160004
SECTION: HOMES PAGE: D-1 EDITION: METRO
COLUMN: Dear John
SOURCE: JOHN ARBOGAST
Every year some azaleas, especially those in sunny spots, go into the fall with their color bleached, giving the plant a weakened appearance.
This is the time to examine your azaleas to see if lacebugs are present and to initiate control if necessary before the damage becomes severe.
Lacebugs damage plants by sucking leaf sap. Adult and young azalea lacebugs are found on the underside of the leaves. Adults are about one-eighth of an inch long and have lacy wings with brown and black markings. The young lacebugs have spines or protrusions around their bodies and are colorless at first but turn black.
Some excellent clues to the presence of azalea lacebugs are: brown or black pinhead-sized spots left by lacebugs on the underside of the leaves; the upper sides of leaves marked by whitish specks, which might be numerous over the whole leaf or on only a part of the leaf at this time; leaves that look dull gray or later even copper colored because the normal green has been bleached.
If several lacebugs are found, use Orthene or diazinon as directed on the label. Because the bugs remove juices from the underside of leaves, try to direct the spray to the underside as far as possible. Be sure to check your azaleas again in late summer to see if lacebugs are once again present and another spray is needed.
Q: Three years ago my husband planted a white grape vine. Last year there were many clusters of grapes, but they all turned to "raisins." We blamed that on the weather. Now this year, it is doing the same thing. There is a huge black walnut tree that hangs over the vine and and the tree's trunk is less than 20 feet away. Could this be causing the grapes to dry up so early or is something else causing the problem? Mrs. S., Clifton Forge
A: Even though black walnut trees do take a lot of moisture, my guess is that your grapes are suffering from "black rot." To verify this possibility, look on the leaves for the other less noticeable symptom of this disease, which would be rusty-looking, reddish-brown leaf spots. This fungal disease is preventable through sanitation, which means removing all blackened grapes and nearby infected canes, plus repeated thorough sprays with a fungicide recommended for black rot control. Start with an application when the new grape shoots are only one or two inches long and continue until shortly before harvest. According to the '96 recommendations from Virginia Tech, the fungicide Ferbam is effective against black rot, but I'd say that it's too late to begin applications now after symptoms have been seen.
Send short questions about your lawn, garden, plants or insects to Dear John, c/o The Roanoke Times, P.O. Box 2491, Roanoke, Va. 24010-2491. We need your mail, but this column can't reply to all letters. Those of wide appeal will be answered during the weeks that the subject is timely. Personal replies cannot be given.
Please don't send stamps, stamped envelopes, samples, or pictures.
Gardener's checklist
Jobs for the third week of July:
Take care in harvesting fruits and vegetables to avoid injuries that might provide entry sites for disease organisms.
In cases where vegetables are difficult to remove, such as cucumbers, watermelons and peppers, cut rather than pull.
Restrict the use of lawn weed killers while the turf is under heat stress.
LENGTH: Medium: 65 linesby CNB