Roanoke Times
Copyright (c) 1995, Landmark Communications, Inc.
DATE: SUNDAY, December 19, 1993 TAG: 9312200322
SECTION: MISCELLANEOUS PAGE: E-1 EDITION: METRO
SOURCE: John Arbogast
DATELINE: LENGTH: Medium
Drafts, too cool or too warm temperatures, sudden temperature changes, dim light, dry atmosphere, letting the plant get bone dry or keeping the soil soggy can cause loss of poinsettia leaves and withering of those colorful parts, which are actually modified leaves called bracts.
To keep a poinsettia looking attractive, strive for a uniform day temperature from 70-75 degrees (a little cooler at night); a location of bright light but no direct sun (a poinsettia can be used as a centerpiece, but put it back near its window as soon as possible); and reasonably humid air, certainly not where dry heat from a heating duct blows on it. The potting soil should be maintained at moderate and uniform moisture levels, neither too wet nor too dry.
Please note that the poinsettia is a poisonous plant, as had been thought. Although some people are allergic to its sap (it contains latex that can cause a skin rash), the plant and all its parts have been shown in clinical studies to be nontoxic, according to Dr. Kevin Grue JOHN ARBOGAST ber, a former extension specialist in floriculture at Virginia Tech.
Q: I recently purchased a home that has pine trees (white pines) situated along the property line at the side of my house. Of the 10 or so pine trees, two are brown and appear dead. Please answer the following questions: Are these trees with brown needles dead or is there a chance that they will come back? What might be a reason that they are dying and can this spread to the others? If they are cut down, can another be planted at or near the same location with roots of the dead tree still present? When is the best time to replant, or when is the time not to replant? D.T., Troutville
A: Once the pine needles turn brown, they are dead. New growth can come out only from the parts having green needles. So, if some of your white pines have completely turned brown, those trees are dead and should be removed.
It is not possible for me to say why two of the white pine trees in your row apparently have died while the others are looking normal.
I get this same question repeatedly from homeowners who have lost certain white pines in a row with others that look normal. Thus, I can't say for sure whether or not the problem will spread.
Here are the possibilities that come to mind:
"White pine decline in landscapes," a broad term that is given to the loss of selected pines in a planting usually due to stresses from poor or heavy soil.
Moisture problems such as poor drainage or drought conditions, or other site-related factors that will affect weaker white pines or those with inadequate root systems.
White pine root decline, a fungal disease that has been found to affect white pines in wet sites.
Insects that would affect the trunk, such as bark beetles or borers; root nematodes, which would include several species of microscopic worms that can live in the soil and feed on white pine roots.
A combination of any of these.
In order to determine why some white pines in a row died and others didn't, one would need information such as when the tree died (how long ago and time of year); was the death fast and all over a pine or slow and progressive, starting with certain branches or parts; and clues on the tree such as sap running down the trunk, injury evidence like bark that has been gnawed off by rodents or presence of scattered holes and sawdust.
If you don't see any clues, contact your local Botetourt County Extension Office at (703) 473-8260 to ask about having a nematode test run at Virginia Tech.
In cases where the cause of death of a prior plant is hard to determine or was never discovered, the stump of the former plant, as much of the big roots as feasible, and sawdust or wood chips left from that cut tree should be removed before a new plant is installed in that spot.
If you will replant with nursery-grown, ball and burlapped pines, that operation can be done at any time of year that water is available except when the ground is freezing or during a time of heat stress. However, if you hope to replant by digging and transplanting white pines already growing somewhere else to be moved to your row, that should be done when the plants are dormant and the soil is at a mild temperature, which means mid-fall or late winter.
Send short questions about your lawn, garden, plants, or insects to Dear John, c/o the Roanoke Times & World-News, P.O. Box 2491, Roanoke 24010-2491. We need your mail, but this column can't reply to all letters. Those of wide appeal will be answered each week. Personal replies cannot be given. Please do not send stamps, stamped envelopes, samples or pictures.
Gardeners' checklist
(Jobs to be done in mid- to late December)
Do you need evergreens that can provide some color in future winters or for privacy? Evergreens also are used to reduce street noise and block the glare of street lights. Plan now so that you can be ready for the spring planting season.
by CNB