Tree Doctor: Pests and Disease

North American now has a long record of attacks by foreign bugs and disease on vulnerable species.  The first exposures, of course, were when our Native Indian populations were decimated by European disease, like measles, chicken pox, and small pox.  Now, even for plants, it is as if geographic barriers no longer exist.  The Earth has become a smaller place.  And diseases and pests that were confined by winter are now moving northward.

Our most immediate present problem is Emerald Ash Borer.  The next challenge will be the Thousand Cankers disease in Black Walnuts, just discovered to have arrived from the West coast.
At some point, we will be seeing Wooly Hemlock Adelgid in our Urban hemlocks (now in the Eastern Forests of Daniel Boone and North Carolina), and the Asian Long-Horned Beetle (being fought in Worcester, MA.  It loves maples.  It was recently found in Ohio.)  We already have substantial ongoing damage to our dogwoods from Dogwood anthracnose and powdery mildew.

And of course, back in the 1930s, all our American chestnuts died from chestnut blight.  And we continue to lose large elms to Dutch Elm Disease.  The huge tree in Curlew developed signs of  Dutch Elm Disease during the drought, and then came down in the Ice Storm.   (By the way, you can treat Elms by injection, using similar methods to those for treating Emerald Ash Borer.)

Learn how to recognize challenge and manage your trees.  At some point, a new equilibrium will emerge.  In the meantime, we can learn more about these threats, and diversity our tree plantings, and choose resistant cultivars.  We will be replanting elms that are resistant to Dutch elm disease, and American chestnuts with blight resistance.  We will be testing new dogwoods from the University of Tennessee program for resistant dogwoods.  Replanting is a key strategy.

Stay tuned, and be aware enough to recognize problems with your trees.

Ash Evaluation and Preventative Treatment for Emerald Ash Borer

We will be visiting households with ashes this summer to evaluate trees, and to give you information on treatment.  The attached file is excellent on describing various treatments for Ashes.  You will want to compare the certain cost of removal and replanting, and the lost of a major tree, with the cost of treatment every three years (like an insurance policy against EAB).  We have had contacts with Joe Clayton of Arbor Worx, with Limbwalker Arborists, and with Gregory Stephens from Natural Resources and Property Management.  All of these people are reputable trained sources to evaluate trees for treatment.  Other arborists are also training and gaining experience.  Be sure you are dealing with a local trained certified arborists with good references, since treatment is expensive and an on-going process.

The most current information about Kentucky is found at the U KY Extension Service Site.

Anne Bobigian,
Feb 14, 2012, 12:09 PM