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Posted by jack , May 31,2005,17:45       Forum

Oak lover's beware. I'm located in the Great Lakes region of North America, and something around here has been killing Oak trees 2003-05 at an alarming rate. These are mature canopy trees 90-100 feet tall, with uninterrupted branchless trunks soaring up to 40-50 feet, then a canopy of leaves and branches 50-60 feet thick topping out at the trees 90-100 foot height. Smaller Oaks and, oddly dogwoods also are effected. These are the symptoms......The first symptom is one many may not notice unless looking for it, in mid summer, in a mature healthy normal tree, a color shift in the leaves from dark verdant green to light green. This tree's leaves will then get their 'Autumn color' a month or more early, and the leaves will drop for winter before the other Oaks. The next year the tree will bud normally, but then the buds will either fail to leaf out at all, or leaf out on only 10% to 70% of the tree. The early Fall color change and winter drop will happen even earlier this year (July-August) and the next Spring the tree will be totally dead. Variations are......sometimes the tree will be totally dead the first summer after the color shift, sometimes it'll linger for 3 summers. In about 70% of these trees insect bore holes (round, oval, 'D' sphaped and small like nail or ice pick holes) will be visable in the trunks the first Spring of dead or unleafing branches. In another 25% of the trees insect bore holes will be visable beneath grasses and leaf litter at the trunks 'margin' (right where the trunk wall actually enters the ground, usually behind vegatation) or the trunk will be wet or decayed at this point that same first Spring/Summer. Oozing sap leaks or wet spots might also be visable low on the trunks.
The culprit in all this, at least around here, doesn't seem to be the foreign Gypsy Moth, or the lethal cancer like killer of Oaks, Oak Wilt,or anything else exotic, but the not often heard about North American native predators of Oaks....the Oak Borers (Two Lined Chestnut Borer, Red Oak Borer, White Oak Borer, Oak, Chestnut and Carpenter Timberworm....beetles about 1 inch long, skinny and flat, that lay their eggs in bark crevices, and whose young in their larve (worm) phase live inside the tree. The holes you see in the tree are exit holes and mean when you see them the insects have been living and eating inside your tree for 1-2 years and have chewed their way out to mate and lay more eggs. Here's some web,, In my area about 25 giant Oaks have been killed or are near death in these last 3 years (usually in groups of 3-6 trees at a time). If anyone in the area of Michigan, Ontario, Minn., Wisconsin, Western New York is experiencing similar conditions I'd like to hear about it please.

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