Q: I have been advised that there is a beetle that has become a threat to black walnut trees (and their relatives), that it is in the Western United States, and that the bug could cross the Mississippi River soon. I was also advised that walnut grown west of the Mississippi River should not be brought (or shipped) to anywhere east of the Mississippi River to prevent the disease from spreading.
I also heard that a beetle has invaded North America from China. It is attacking ash trees, and some foresters are saying that it will probably wipe them off the face of the continent.
Is there truth to these stories, or are they just legends?
A: Both of the stories you have talked about are true. The black walnut tree threat (known as 1000 Cankers disease) is in many Western states and, according to some unverified reports, has crossed the Mississippi River to the east.
The emerald ash borer is moving unchecked across our Eastern hardwood forests. Barring a successful chemical or biological treatment, it will certainly be the end of the ash tree population as we know it.