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I have an ancient elm, its circumference is 20.5 feet at approximately 2.5 feet from the ground. This beautiful tree appears to be in good health except it has started to weep in a couple of places where large branches join. The bark looks wet, but I don't actually see anything oozing from these places. A whitish streak runs down from where it seems to be weeping. There is also a spot where there once was a larger branch that seems to be wet. What is this?
What you describe sounds like elm wetwood, a bacterial infection that commonly occurs under the bark of elm trees. See University of Illinois at Urbana-Champaign Web site for a description of the problem. Though not an imminent threat to the tree, it may indicate the beginning of a gradual decline. There is no very effective treatment, nor is treatment required.
Chris Starbuck
State Extension Specialist
Woody Ornamentals
I'd like to move a newly planted row of boxwoods. Root stimulator was applied when they were planted. Will it stress the plants to move them again this weekend or should I let them rest for awhile?
I think it would be best to move them as soon as possible. I am assuming that they are container grown plants, in which case, there will have been no root growth yet out of the soil balls. They should not even know that they have been moved.
Chris Starbuck
State Extension Specialist
Woody Ornamentals
I want to use paper birches as a formal guide around existing brick pathways. Each planting bed is 10 to 12 feet wide and 20 to 30 feet long. Walks and patios surround the beds. The bricks are on a 1-inch base of sand. Will the roots of this type of tree disturb the layout of the bricks?
I think your concern is well founded. It seems likely to me that as the trees mature, they will root out under the bricks and pavers and cause a certain amount of heaving and buckling. I don't think paper birch is any more likely to cause a problem in this situation than most other tree species. If you want to keep the bricks perfectly level, this will become increasingly difficult. However, I suspect that the problem will not develop significantly until 10 or 15 years from planting. If you are willing to tolerate some unevenness in the walkway after about 10 years, go ahead with the project.
Chris Starbuck
State Extension Specialist
Woody Ornamentals
I saw a big tree. Its leaves were almost square without a point. Scattered over the tree were flowers like magnoilias, but smaller. The flowers were yellow and red or yellow and orange with spikey things in the middle. The flowers smelled like a fresh cucumber. Can you identify this tree?
You described the plant very well. There is only one thing that it could be -- tulip poplar, or yellow poplar (Liriodendron tulipifera). It is actually in the magnolia family.
Chris Starbuck
State Extension Specialist
Woody Ornamentals
I have two 14-year-old quaking aspens about 35 feet tall, six inches in diameter, planted about three feet apart in my backyard. After a week of heavy rain and a day of high winds, both trees are leaning east about 10 degrees off center. On the west side of the tree there is a space about 1.5 inch between the trunk and the soil. Will these trees try to regain their stance, continue to lean more? Are the roots permanently damaged? What am I to do?
The situation you describe resulted from a combination of saturated soil and strong wind. Generally, once the soil dries out the trees will become stable again. Eventually the trees will straighten themselves, but there will be a slight curvature to the trunks. In my opinion, there is nothing you need to do.
Chris Starbuck
State Extension Specialist
Woody Ornamentals
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Updated 5/19/08