THE VIRGINIAN-PILOT
Copyright (c) 1996, Landmark Communications, Inc.
DATE: Sunday, April 21, 1996 TAG: 9604200061
SECTION: HOME & GARDEN PAGE: G2 EDITION: FINAL
COLUMN: GARDENING
SOURCE: Robert Stiffler
LENGTH: Medium: 93 lines
Q. My question is about our dogwoods, which a few years back began to have stunted blooms that didn't open. Petals were sealed together and, though they turned white, they did not open much. The problem has spread to other trees nearby and last year I noticed trees along the road with similar distorted blooms.
Also can you identify a tree from leaves and thorns enclosed? It was a volunteer in our yard and has grown to 6 feet tall in three years. It is full in shape, rather more like a shrub than a tree, with a brown trunk and green, thorny branches. Last season, it bore green fruit, one of which is turning yellow and looks like a small round lemon. Someone identified it as a citrus tree, and it surely looks like one but it sheds its leaves in winter. But citrus in Kitty Hawk?
Ruth Gaeta, Kitty Hawk, N.C.
A. Your dogwoods may have a scale problem. Scale are cyclic, say Virginia Tech authorities, and cottony scales are common. An application of horticultural oil should control them.
Another cause could be dogwood borer, says entomologist and Research Center Director Peter Schultz. Borers often result from a mower or string trimmer wounding the tree. Oozing sap from the trunk is a sign of dogwood borer infestation. Control is by treating the trunk in May with a borer spray. Lindane and Thiodan are most often recommended.
Your volunteer tree is Trifoliate orange, a close relative of oranges. Officially, it is poncirus trifoliata and is often seen in this area. It is used as root stock for oranges in Florida, to increase their hardiness.
Q. Your column in November stated that Virginia Tech authorities were baffled as to the cause of leaves yellowing around the edges on trees and shrubs in this area. Perhaps they should consider Command as the cause. It is a herbicide used for weed control on cotton. When it vaporizes, it changes the chlorophyll in the leaves. After a rain, when the air heats up, it can affect leaves on trees one-half mile from the source. This was a major problem in Southampton, Sussex and Greenville counties last summer.
Mrs. Burton E. Grizzard, Capron
A. Perhaps the word ``baffled'' was misleading. Often from the limited amount of information given by readers, it is difficult for any expert to diagnose all problems.
As to Command, Virginia Tech herbicide specialist Jeff Derr says it will turn foliage white. It generally bleaches new growth and can drift for a distance, affecting tree and shrub foliage. He says that plants will outgrow the problem. He also says homeowners should make sure, before blaming Command, that the problem is not caused by excess salts or excess fertilizer, which causes yellowing around the edges of leaves.
Q. My sister-in-law brought back from Louisiana a tree she called a
``Grantzy Graybeard.'' In spring, it is covered with sprays of what look like miniature spider mums. They stay in bloom almost all summer and are very beautiful. Can you tell me what it might be?
My second question concerns small dahlia plants. I was delighted with their colors and profusion of blooms all summer long. I didn't notice any bulb-like structure when I planted them, but I would like to know if they winter over and come up again in the spring.
Sara Flournoy, Norfolk
A. Your tree is fringe tree, Chionanthus virginicus. It is also called old man's beard tree and is native to the Southeastern United States. If there is another tree nearby for pollination, the blooms are followed by blue berries borne in grapelike clusters.
As to your dahlias, they will winter over, provided they have good drainage and are planted deeply enough. Because yours were purchased in pots, they should have been at the right depth in the soil. They need protection for their crown, so you should have covered them with mulch. Do not cut off the foliage after it is killed by frost. Let it fall down and act as a natural mulch.
Q. I planted some seed and can't remember what it was. The plants on the photo enclosed came up from the seed. I thought at first they were sunflowers, but they aren't. They grew as tall as the house, but no blooms or branching as yet. Can you tell me what the plant is and is it desirable for my yard?
Jestive Keene, Norfolk
A. Your tree has large, rough, dark green leaves and it is Paulonia or the empress tree. It is grown in the Orient and harvested for its valuable wood. You see many of them in the Brandywine valley of Pennsylvania, where it has long panicle, purple blooms somewhat like wisteria. Whether it's a valuable tree depends on what the owner likes. Pinch the top out and force it to branch out. Let it grow old enough to bloom, and then you can decide whether or not you like it. MEMO: No gardening questions will be taken over the phone. Write to Robert
Stiffler, The Virginian-Pilot, 150 W. Brambleton Ave., Norfolk, Va.
23510. Answers will be published on a space-available basis. For an
earlier reply, send a self-addressed, stamped envelope.
by CNB