Oak Decline May Continue In 2026

A wide view of declining oak trees following spongy moth defoliation and drought.

Oak trees with thin canopies experiencing decline following spongy moth defoliation and drought in the prior few years. / Photo Credit: Wisconsin DNR

By River Mathieu, DNR Forest Health Specialist, Fitchburg
River.Mathieu@wisconsin.gov

Oak decline is a complicated forest health issue impacting oak forests in Wisconsin.

In the past few years, oak decline has been recorded in several regions of Wisconsin, primarily linked to spongy moth defoliation and drought conditions that occurred from 2022-2024.

As the summer months of 2026 continue to unfold, oak decline may continue in areas previously impacted by spongy moth and drought.

Continue reading “Oak Decline May Continue In 2026”

Species Spotlight: Red Hailstone

A large creeping vine blankets neighboring trees and plants.

A red hailstone infestation in Dane County blankets surrounding vegetation and can be seen climbing into trees. / Photo Credit: Wisconsin DNR

By Carter Hellenbrand, DNR Invasive Plant Field Specialist, Fitchburg
Carter.Hellenbrand@wisconsin.gov

Note: This is the third installment in the Forest Health News “Invasives Spotlight” series, a series of articles released monthly during the growing season.

What is heart-shaped and hairy all over? Red hailstone!

Two hands holding tubers of the red hailstone plant.

Underground tubers of red hailstone. The tubers easily break off to create new plants. / Photo Credit: Wisconsin DNR

Also known as golden creeper or Manchu tubergourd (Thladiantha dubia), this invasive perennial vine can grow 18 feet in a single growing season and spreads through underground potato-like tubers that break off from the root system to create new populations.

 

 

 

Continue reading “Species Spotlight: Red Hailstone”

Watch for Asian Longhorned Beetle

Closeup of an insect crawling on a person's hand.

An adult Asian longhorned beetle. / Photo Credit: Wisconsin DNR

By Michael Hillstrom, DNR Invasive Forest Pest Coordinator, Fitchburg
Michael.Hillstrom@wisconsin.gov or 608-513-7690

Asian longhorned beetle (ALB) has not been found in Wisconsin, but early detection is critical to eliminating it from infested areas. Forest Health workers from Wisconsin, Michigan, Minnesota and Manitoba, Canada, recently had the opportunity to visit an active ALB infestation in South Carolina to learn how to identify infested trees. This experience will greatly enhance staff’s ability to detect ALB and respond rapidly.

Continue reading “Watch for Asian Longhorned Beetle”

Cooperative Enlists Public To Make Tree Health A Snap

A worker speaks with colleagues in a forested area.

Dr. Scott O’Donnell, center, a forest geneticist with the Wisconsin Department of Natural Resources Forest Economics and Ecology section, updates members of the DNR Forest Health team on upcoming genetic projects at an orchard near Lake Tomahawk in Hazelhurst during the Forest Health team’s summer meeting on May 25, 2024. / Photo Credit: Wisconsin DNR

By Art Kabelowsky, DNR Outreach and Communications, Fitchburg
Arthur.Kabelowsky@wisconsin.gov or 608-335-0167

It takes more than a village to foster healthy forests. More than a township, a city and a county, too. Sometimes, even more than a state.

That’s why the Great Lakes Basin Forest Health Cooperative (GLB FHC) was formed five years ago by Holden Arboretum in Ohio and the U.S. Department of Agriculture Forest Service.

Geographically, the group’s region encompasses an area from New Jersey to Wisconsin. The Wisconsin Department of Natural Resources (DNR) is an active member.

Continue reading “Cooperative Enlists Public To Make Tree Health A Snap”

2027 Urban Forestry Grants Announced

By Nicolle Spafford, DNR Urban Forestry Grant Manager
Nicolle.Spafford@wisconsin.gov or 715-896-7099

aerial view of neighborhoodBeginning July 1, 2026, cities, villages, towns, counties, tribes and 501(c)(3) nonprofit organizations conducting projects in Wisconsin can apply for a regular or startup 2027 Wisconsin Department of Natural Resources (DNR) Urban Forestry grant. Continue reading “2027 Urban Forestry Grants Announced”

The Urban Forestry Staff Springs Into Action For Arbor Day

Laura Buntrock hosted an urban forestry booth at Rhinelander’s Earth Day Sustainability Fair, where she educated the public on the benefits of urban trees, provided resources and answered questions.

April and May might just be the busiest months of the year for the Urban Forestry staff. This small but mighty team participates in as many Arbor Day, Earth Day and Forest Appreciation Week events as they can fit into their schedules. Municipalities, schools and nonprofits tend to spread out their events over a couple months rather than scheduling them all on Arbor Day, which allows the staff to get to more events.

The Urban Forestry team’s involvement in these events varies and can include tree planting, seedling distribution, education and tree-related activities, such as competing for the loudest Arbor Day cheer. If you have an event you would like an Urban Forestry staff member to attend at any time of the year, get your request in early!

Here are just a few of the events that Urban Forestry staff attended. Continue reading “The Urban Forestry Staff Springs Into Action For Arbor Day”

Urban Forestry Welcomes Summer Interns

The Urban Forestry team is excited to have two interns this summer through the State of Wisconsin Student Development Internship Program (SWSDIP). They will be working out of the Milwaukee DNR office but will also have opportunities to get involved in projects in other parts of the state. The Urban Forestry interns always hit the ground running, squeezing an impressive number of activities into their time with the program. Watch for an article later in the year summarizing their experience with the Urban Forestry program. Continue reading “Urban Forestry Welcomes Summer Interns”

What’s In A Name? An Intro To Reading Scientific Names

By Abby Krause, DNR Urban Forestry Coordinator
Abigail.Krause@wisconsin.gov or 608-556-5690

What’s in a name? That which we call a tree by any other name would stand as tall. Okay, maybe that’s not exactly how the Shakespeare quote goes, but in the urban forestry world, what we call a tree does play into our management decisions.

As communities work to recover from the devastation inflicted by invasives pests and build resilience against future challenges, species diversity rules have become the guide for planting projects. Planning out care of trees once they’re in the ground also revolves around knowing which species are present. How are we tallying our progress toward diversity goals, relaying the specific species we want to order from the nursery or narrowing down what’s ailing that tree in the park? Continue reading “What’s In A Name? An Intro To Reading Scientific Names”

Maple Leaf Blister And Anthracnose: Two Diseases Of Maple Leaves

By Nathaniel WaltonMichigan State University Extension

Updated from an original article written by Diane Brown and Lori Imboden

Irregularly shaped anthracnose lesions on a red maple (Acer rubrum) leaf. Photo by Rebecca Finneran, MSU Extension.

Each year, Michigan State University Extension receives questions from the public regarding spots on the leaves of their favorite maple trees. Both anthracnose and maple leaf blister can be the cause of late spring and early summer damage to leaves of these popular landscape trees. Continue reading “Maple Leaf Blister And Anthracnose: Two Diseases Of Maple Leaves”

Upcoming Training & Events

* These training opportunities are provided as an information service only and do not constitute endorsement by the Wisconsin Department of Natural Resources (DNR).

group of adult learning to identify treesSee below for information on training topics and events, including the WAA Summer Conference, leadership, pollinator habitats, safety, tree ID and the ISA Annual Conference. Continue reading “Upcoming Training & Events”