A fungal pressure pad formed on the outside of the sapwood underneath the bark of an infected tree. The pad will create cracks in the bark, where beetles can enter and visit the pad and become covered in spores. They will then leave and move on to infect new trees through open wounds. / Photo Credit: Wisconsin DNR
By Alex Hornung, DNR Forest Health Specialist, Plover
Alexandra.Hornung@wisconsin.gov or 715-340-3810
It is again that time of year to pause operating in oak stands or pruning oak trees during the high-risk period for oak wilt, which begins in April. The high-risk period begins April 1 in the South, April 15 in the North, and ends in both zones on July 15.
The high-risk period is determined by when the beetles that carry the fungus that causes oak wilt have emerged for the year and when they are carrying the highest number of fungal spores. When wounds are created by logging operations or other activities that expose sapwood, the beetles carry the fungus to the wounded tree, and the disease process begins.
Continue reading “Oak Wilt High Risk Period Quickly Approaches”
* These training opportunities are provided as an information service only and do not constitute an endorsement from the Wisconsin Department of Natural Resources (DNR).
To best answer the titular question, I like to start by flipping the question on its head: When is the worst time to prune trees?
* These training opportunities are provided as an information service only and do not constitute an endorsement from the Wisconsin Department of Natural Resources (DNR).
To say that working on a Christmas tree farm in high school led me into forestry would be a case of significant historical revisionism. Still, that experience swam in the same waters as reading Lord of the Rings, going on family vacations to the mountains, having a nearby municipal forest and other things that showed me that trees were the way.
*These training opportunities are provided as an information service only and do not constitute an endorsement from the Wisconsin Department of Natural Resources (DNR).
Reliable and up-to-date research-based information is vital for tree care professionals and urban foresters to make sound, scientific management decisions. To make trusted resources more accessible, UW-Extension’s 