pin oak not vigorous

[kc88]

We have two oak trees that are as tall as our two-story house. They were planted in late 1999 (when the house was built), but have never really been in the "Leap" status - seems all they do is sleep or creep.

On both trees, some branches never had leaves. On one of them, the main trunk has black marks off to one side from the ground up for at least 8 feet - it almost look like the bark on the trunk in certain places have been burnt. In the summer I sometimes see wasps flying in and out of the tree - no nests seen - so I wonder if they are there for the sap...

The trees are in zone 7, front yard, full sun. They stand in the middle of the lawn on clay soil.

And what I dislike about these trees the most are the dead leaves hanging through winter all the way into spring. But I can forgive this feature if they are at least vigorous growers in spring and summer. Is there anything I can do to help these trees?

Thanks!!

[pruninggal]

Hi kc88,

Here's a great link about pin oaks. Perhaps the problems they describe might jive with your description - of particular interest: "In urban areas, Pin Oak suffers from a quirk of commercial nursery production, in that most trees originate from southern sources with very acidic soils, and when transplanted to neutral or alkaline soils, suffer tremendously from leaf chlorosis with a resulting loss of vigor. The lesson still not learned is to use local seed sources for growing trees, when there will be a problem of any type."

http://www.dnr.state.oh.us/forestry/...ees/oakpin.htm

Good luck,
Pruninggal