Oak Abuse, Part 4

We received notification from the Plant Disease Clinic: It is oak wilt. This is one of those cases where you hate to be right, and wish you had been wrong.

Now comes the task of protecting the adjacent trees from the fungus. Now that one tree got infected via the inefficient means of a picnic beetle carrying fungal spores from a diseased tree to the May 22 pruning wounds made on this tree, oak wilt now becomes a much deadlier threat, spreading at an approximate rate of 30 feet per year through the roots from one tree to the next.

Oak wilt transmission overland via the picnic beetle is a question of "if." Transmission via the root systems is a matter of "when." Oak trees form root grafts with nearby oaks of the same species - northern red oak to northern red oak, bur oak to bur oak, etc. Whether this is an example of aboreal socialism which allows a stand of oaks to share water and nutrient resources, or is a Darwinian means by which stronger oaks draw upon the resources of weaker ones, I don't know.

What I do know is it makes a great highway by which systemic fungal infections can travel from one oak tree to the next... and the next... and the next.

But we have been hard at work getting the right people involved in preventing the spread of the fungus to adjacent trees, and these experts have more tools at their disposal than they did 20 years ago when I was first learning about and giving talks about oak wilt.