Earlier this week, I attended the First Detector Forest Pest training program put on by the University of Illinois Extension Service in Springfield, IL. It focused on different invasive species that threaten native plants or have the potential to cause major financial impacts on local economies in an effort to control these pests.
The first pest discussed was the Emerald Ash Borer which is causing the death of literally millions of trees in the Midwest and is moving outward from there. Currently, it can be found in 15 states and in Canada and has the potential to make its way across the entire continental U.S.
The second forest pest discussed is known as Thousand Cankers Disease, which has the potential to attack various species of walnut trees. This disease is produced by the combined activity of a canker producing fungus and a boring beetle called a Walnut Twig Beetle. The tiny, about 1 mm in length, beetle is covered with tiny hairs that can trap the spores of the disease. When it bores into the tree to lay eggs, the spores dislodge and begin infecting the tree. This disease has devastated plantings of Black Walnut in several western states and has now been identified in parts of Tennessee, Virginia and Pennsylvania.
This disease has the potential to seriously affect the timber industry in Illinois and surrounding states. I learned that the value associated with the harvesting of Black Walnut trees in Illinois ranges from $13,000,000 to $18,000,000 a year. Missouri, a close neighbor to Illinois, is one of the largest producers of walnut wood products and the spread of Thousand Cankers disease could have an even greater financial impact on that state.
We also discussed three major invasive weeds – Oriental bittersweet, Japanese Stiltgrass and Giant Hogweed. Of the three, Giant Hogweed seems to be the one that is of most concern. Giant Hogweed grows 8 to 15 feet high with very large leaves and giant flowers called umbels. The sap of this plant is photo-reactive and if it gets on one’s skin and then isexposed to UV or sunlight, severe blistering and skin rashes can occur. It is like the reaction to Poison Ivy, but on a much greater scale.
An important part of the course was how to scout for these problems and how to submit samples. I am glad that I now know more about these problems and will definitely be on the lookout for them.