Invasive Species – Fall Workshops

By Olivia Witthun, DNR Urban Forestry Coordinator; Olivia.Witthun@wisconsin.gov or 414-750-8744

The Wisconsin Department of Natural Resources is partnering with the UW-Madison Division of Extension to host a series of fall workshops on invasive species plant identification and management. Learn about invasive plants in urban settings, focusing on identification, impacts, management and available resources. Dr. Mark Renz (professor and Extension specialist with UW-Madison) will lead the instruction, with Travis Wilson, Matt Wallrath and John Zabrosky assisting. Each workshop will include morning classroom instruction followed by hands-on field demonstrations in the afternoon. The cost of the workshop is $40 and includes lunch. Continue reading “Invasive Species – Fall Workshops”

Collaborative Reforestation – Sheboygan Area School District

By Tony Fessler, Co-Coordinator – Restoration Of Our Trees Sheboygan, www.sheboyganrotary.com or 920-946-6770.

Photo Credit: Tony Fessler

A collaborative urban reforestation project involving the Sheboygan Area School District, the Sheboygan Rotary Club Restoration of our Trees Sheboygan (ROOTS) and the Lakeshore Natural Resource Partnership (LNRP) completed a second major milestone on May 10, 2025.  This first-of-its-kind urban reforestation collaboration was initiated in 2024 through a matching $25,000 Wisconsin Department of Natural Resources (DNR) Urban Forestry Grant to ROOTS and LNRP.  Continue reading “Collaborative Reforestation – Sheboygan Area School District”

NASF Accepting Award Nominations

The National Association of State Foresters (NASF) is accepting nominations for its 2025 awards. Only nominations submitted on or before Friday, Aug. 1, through this online form will be considered. Descriptions of the awards, guidelines for selection and a sample nomination are included on the first page of the online form. The awardees will be honored in person and virtually at the 2025 NASF Annual Meeting in Waimea, Hawaii. Continue reading “NASF Accepting Award Nominations”

Upcoming Trainings

group of people listening to a speaker in the woods*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, including biochar, advanced arboriculture, selecting resilient tree species, The National Urban Tree Canopy Application, invasive species, wildlife and educational resources. Continue reading “Upcoming Trainings”

Armillaria Root Disease: A Fungal Killer

A photo showing that after bark has been removed from a declining white spruce, the white mycelial mat of Armillaria can be seen under the bark.

Bark has been removed from a declining white spruce to show the white mycelial mat of Armillaria under the bark. / Photo Credit: Linda Williams, Wisconsin DNR

By Linda Williams, DNR Forest Health Specialist
Linda.Williams@wisconsin.gov or 920-360-0665

Armillaria is a root-rot pathogen that usually lives quietly under the soil. But when trees experience stress, the fungus can attack and colonize the roots of the stressed tree.

Armillaria can infect many different species of trees, and trees of any age or size, but the result for the tree is usually a slow decline and eventual death. Stressors can include drought and flooding, defoliation from insects or diseases or physical damage such as when roots are severed.

Continue reading “Armillaria Root Disease: A Fungal Killer”

New Forest Health Specialists Take To The Woods

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

It’s time for River Mathieu and Tim Shively to put all their education and research to work.

Mathieu and Shively are the newest additions to the Wisconsin Department of Natural Resources (DNR) Forest Health team. Both started on June 30, filling Forest Health Specialist vacancies.

Continue reading “New Forest Health Specialists Take To The Woods”

Gall Causes Bull’s-eye Spots On Maple Leaves

A photo showing that maple eyespot galls have created colorful, concentric patterns on red maple leaves.

Maple eyespot galls create colorful, concentric patterns on red maple leaves. / Photo Credit: Linda Williams, Wisconsin DNR

By Linda Williams, DNR Forest Health Specialist
Linda.Williams@wisconsin.gov or 920-360-0665 

Colorful “bull’s-eye” spots on maple leaves are maple eyespot galls, caused by the tiny ocellate gall midge (Acericecis ocellaris).

The adult midge lays eggs on the underside of the leaves. Once the eggs have hatched, the larvae feed on the leaves. That feeding causes the leaf to develop telltale colorful, concentric circles in that area of the leaf.

Continue reading “Gall Causes Bull’s-eye Spots On Maple Leaves”

Dusky Birch Sawfly Larvae Defoliate Birch Leaves

A closeup photo showing that while feeding on a white birch leaf, dusky birch sawfly larvae raise into an S shape when a potential predator is noticed.

While feeding on a white birch leaf, dusky birch sawfly larvae raise into an S shape when a potential predator is noticed. / Photo Credit: Linda Williams, Wisconsin DNR

By Linda Williams, DNR Forest Health Specialist
Linda.Williams@wisconsin.gov or 920-360-0665

Dusky birch sawfly (Croesus latitarsus) is a native sawfly that feeds on white birch and occasionally river birch and yellow birch. Larvae feed in a group at the edges of birch leaves and abandon part of the midrib before moving on to another leaf.

Defoliation is typically light, with a few dozen leaves per tree being eaten. This defoliation is only problematic on young seedlings with few leaves. There may be two generations of larvae in a year.

Continue reading “Dusky Birch Sawfly Larvae Defoliate Birch Leaves”

Veiled Polypore Fungi Growing On Red Pine Bark

Closeup photo of veiled polypore fungi showing as yellow, leathery fruiting bodies on the bark of dead red pine trees.

Veiled polypore fungi show as yellow, leathery fruiting bodies on the bark of dead red pine trees. / Photo Credit: Linda Williams, Wisconsin DNR

By Linda Williams, Forest Health Specialist
Linda.Williams@wisconsin.gov or 920-360-0665

You may have seen these leathery, yellow fungi growing on recently dead red pine trees and wondered if they were what killed the tree. The short answer: No, they did not kill the tree.

The veiled polypore (Cryptoporus volvatus) is a decay fungus that grows on the bark of red pine in the year after they die. They can be found anywhere on the trunk of the tree.

Continue reading “Veiled Polypore Fungi Growing On Red Pine Bark”