* These training opportunities are provided as an information service only and do not constitute an endorsement from the Wisconsin Department of Natural Resources (DNR).
See below for information on training topics and events, including tree diseases and treatments, pest management, landscaping, career advancement, invasive species, pruning, volunteer management, new research, partnerships and developing an urban forest management plan. Continue reading “Upcoming Trainings”
The cover of the 2025 Wisconsin Department of Natural Resources Forest Health Annual Report. / Graphic Credit: Wisconsin DNR
By Art Kabelowsky, DNR Outreach and Communications, Fitchburg
Arthur.Kabelowsky@wisconsin.gov or 608-335-0167
The Wisconsin Department of Natural Resources (DNR) has made its 2025 Forest Health Annual Report ready to view and download.
This year’s edition contains 55 pages of reporting on forest health issues throughout Wisconsin, detailing methods employed by the DNR and other agencies to control pests, diseases and invasive plants.
Continue reading “Forest Health Annual Report Hot Off The Presses”
A stack of discarded Christmas trees awaits processing at a drop-off facility. / Photo Credit: Wisconsin DNR
By Wisconsin DNR
Invasive plants and insects don’t mind playing the long game. After all, they’re just trying to survive and thrive, like the rest of us.
They’ll hang out as part of your holiday decorations throughout the season, just on the chance humans might dispose of them improperly, giving them an opportunity to find a new home in your yard or neighborhood.
Continue reading “Be Mindful Of Invasives During Holiday Clean-Up”
Winners of the 2025 Invasive Species Action Awards, given by the Wisconsin Department of Natural Resources. / Photo Credit: Wisconsin DNR
By Wisconsin DNR
The Wisconsin Department of Natural Resources (DNR) has announced that the Wisconsin Invasive Species Council will accept nominations for the 22nd annual Invasive Species Action Awards through Feb. 15, 2026.
Award recipients are Wisconsin residents and organizations who have made significant contributions to prevent, control or eradicate invasive species that harm Wisconsin’s native forests, wildlife, wetlands, prairies, lakes and rivers.
Continue reading “Invasive Species Action Awards Nominations Open”
Mike Hillstrom became the Wisconsin Department of Natural Resources Invasive Forest Pest Coordinator on Sept. 9, 2024. / Photo Credit: Wisconsin DNR
By Art Kabelowsky, DNR Outreach and Communications
Arthur.Kabelowsky@wisconsin.gov or 608-335-0167
Mike Hillstrom and Bill McNee, members of the Wisconsin Department of Natural Resources’ Forest Health team, made notable radio appearances during November.
Hillstrom, the DNR’s invasive forest pest coordinator, appeared on Wisconsin Public Radio to discuss the invasive pest hemlock woolly adelgid (HWA). The insect has not yet established a presence in Wisconsin.
Mature spongy moth larva on a tree at Potawatomi State Park in Door County, July 2025. / Photo Credit: Wisconsin DNR
By Bill McNee, DNR Forest Health Specialist, Oshkosh
Bill.McNee@wisconsin.gov
Wisconsin’s recent period of high spongy moth populations (an “outbreak”) came to an end in 2025, as the remaining known hotspots were aerially sprayed or naturally collapsed. Only a handful of large larvae were observed or reported by property owners.
Spongy moth populations are likely to be low across the state for at least the next few years. However, it is possible that some sites may experience a population increase before then, if local weather conditions are favorable for the insect.
Continue reading “Increased Tree Mortality Seen As Spongy Moth Outbreak Ends”
A freshly cut tree stump after treatment with fungicide to prevent infection with Heterobasidion root disease. The fungicide is dyed blue to help ensure complete coverage. / Photo Credit: Wisconsin DNR
By Tim Shively, DNR Forest Health Specialist, Eau Claire
Timothy.Shively@wisconsin.gov or 608-772-6974
Treating freshly cut conifer stumps is critical to preventing infection by Heterobasidion species, causal agents of Heterobasidion root disease (HRD).
Within this genus, H. irregulare is believed to be the only species in Wisconsin, and it causes the mortality of overstory pine and spruce trees. The DNR has developed comprehensive guidelines to assist landowners, property managers, foresters, and loggers with determining whether stump treatments are necessary to prevent the introduction or spread of HRD at a given site.
Continue reading “Stumping Heterobasidion Root Disease With Cellu-Treat®”
Witches’ broom on serviceberry. The leaves of this infected shrub are dying because of prolific spore production on their undersides. / Photo Credit: Wisconsin DNR
By Tim Shively, DNR Forest Health Specialist, Eau Claire
Tim.Shively@wisconsin.gov or 608-772-6974
Witches’ broom is a term that describes a disease of many different plants. It’s a distinctive, abnormal growth typically caused by a pathogen — though in some cases it can result from insect feeding.
The namesake symptom appears as abnormally dense clusters of stunted shoots, branches, and foliage that strongly resemble a witch’s broom from storybooks and folklore. In Wisconsin, this is not often a critical forest health concern that merits management action, but Wisconsin Department of Natural Resources Forest Health staff recently observed widespread incidence of two particular witches’ broom diseases.
Jack pine branch tips killed by the jack pine tip beetle. / Photo Credit: Wisconsin DNR
By Linda Williams, DNR Forest Health specialist, Woodruff
Linda.Williams@wisconsin.gov or 920-360-0665
Jack pine tip beetle (Conopthorus banksianae) is a tiny bark beetle that bores into the twig tips of pines. Damage from jack pine tip beetle was observed this summer on jack pine in Vilas County. In some areas, each tree showed 2-10 dead branch tips in its crown.
Continue reading “Jack Pine Showing Dead, Brown Branch Tips”
A group of immature barklice show their characteristic striped abdomens. / Photo Credit: Wisconsin DNR
By Linda Williams, DNR Forest Health specialist, Woodruff
Linda.Williams@wisconsin.gov or 920-360-0665
Barklice, sometimes called tree cattle, tend to congregate in large groups on trees, which can lead some people to worry about tree health. However, they are actually quite harmless.
Immature barklice don’t have wings, so you can see their heavily striped abdomens. Adults have dark-colored wings that form a tent over the abdomen. Both immature and adult barklice congregate in groups.
These insects feed on the algae, lichen and other debris that collects on the surface of tree bark. They do not feed on the tree itself.
