Aliens & Pests

More than half the flowering dogwoods (Cornus florida) in the forests of Mammoth Cave National Park are dead. The trees have succumbed to dogwood anthracnose, caused by the fungus Discula destructiva. While over 3/4 of trees in the park are dead or infected, park ecologists may be able to slow the spread of the disease by managing the forest canopy: the fungus spreads most rapidly in moist understory conditions. These are also the conditions in which dogwoods grow best, but they do well in sparser upland forests as well. Controlled burning may help open up canopies to sunlight, reducing humidity and the threat of infection. (Oddly, the AP article about this issue refers to these trees as 'white dogwoods', rather than the correct name flowering dogwood).

A Michigan tree service owner has been fined $300 for taking "EAB" ("AP") infested firewood from the Detroit area to the Upper Peninsula. Orville Wonsey, owner of OGW Tree Service had a contract to cut infested ash trees in the Detroit area, and was convicted of the misdemeanor count of insect pest and plant disease quarantine violation. Wonsey had taken firewood to two counties, Gratiot and Luce, and sold it, according to agriculture officials. Michigan legislators are now looking to increase penalties for quarantine violations.

Moving infested wood is how the "EAB" gets around quickly. Left to its own devices, "EAB" spreads very slowly. The sole long-distance vector ash borers is people. It is especially egregious for a tree service operator to be involved in spreading this serious pest. It is impossible for such a person to claim ignorance.

Update: The question of whether "EAB" is in the Upper Peninsula is not clear from the news article linked above. Gratiot county is in lower Michigan, and there is an infestation. Luce County is in the UP, and it is not clear whether the movement of firewood by Mr. Wonsey or others has led to an infestation. Time will tell.  Thanks to Jeff B. of the Forestry Forum for clarifying this.