Statewide Forest Health

Is That A Crack In My Tree?

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

tree with frost crackWisconsin winters with subzero weather can create problems for our trees. Frost cracks are one of those problems we’re seeing an uptick of lately. These longitudinal openings can run the entire length of the trunk, often extend deep into the wood, and permanently damage a tree. In wintertime, the tree may even look like it’s splitting in half! Then warmer weather comes, and the crack seems to close, repeating this process annually. Over time, frost cracks may even develop a raised area where callus tissue develops in an attempt to close over the wound, only to reopen again next winter. Continue reading “Is That A Crack In My Tree?”

A Wonderful Winter Display: Phomopsis Galls

Phomopsis galls are plentiful on branches of a 120-year-old red oak tree in Clark County, Wisconsin, in 2024.

Phomopsis galls are plentiful on branches of a 120-year-old red oak tree in Clark County, Wisconsin, in 2024. / Photo Credit: Kris Wimme, retired Wisconsin DNR forester

By Alex Hornung, DNR Forest Health Specialist, Plover
Alexandra.Hornung@wisconsin.gov

It is the perfect time of year to be on the lookout for galls – woody growths or swellings on tree branches that are typically oblong in shape and of varying sizes.

They can often be found on small branches, but occasionally they can affect large branches or even the main stem. Galls can occur for several reasons, ranging from fungi to bacteria to insect activity.

One type, Phomopsis gall, can be particularly impressive to see. Galls formed due to this native fungus mostly occur on oak, hickory and maple trees in Wisconsin.

 

Continue reading “A Wonderful Winter Display: Phomopsis Galls”

Weed Management Area Grant Deadline Approaching

Volunteers at a garlic mustard-pulling event on the Montreal River in Iron County, part of a control project planned by a previous WMA-PFGP recipient.

Volunteers at a garlic mustard-pulling event on the Montreal River in Iron County, part of a control project planned by a previous WMA-PFGP recipient. / Photo Credit: Ramona Shackleford, Northwoods Cooperative Weed Management Area

By Wisconsin DNR

The April 1 application deadline for Weed Management Area-Private Forest Grant Program (WMA-PFGP) grants is coming up. There is still time to apply for funding to help you control invasive plants on your forested land in 2025.

Controlling invasive plants on your forested property can be a challenging and costly endeavor. WMA-PFGP grants help to make this process a little easier for its recipients.

Continue reading “Weed Management Area Grant Deadline Approaching”

Now Is Time To Seek Out Spongy Moth Egg Masses

Large egg masses are seen on a tree at the Kettle Moraine State Forest-Southern Unit in 2021.

Large egg masses are seen on a tree at the Kettle Moraine State Forest-Southern Unit in 2021. / Photo Credit: Bill McNee, Wisconsin DNR

By Bill McNee, DNR Forest Health Specialist, Oshkosh;
Bill.McNee@wisconsin.gov or 920-360-0942

It might be a bit chilly these days, but spring is coming. When the weather warms up, the annual return of spongy moth caterpillars will begin.

There’s a way for landowners to make a dent in the population of the hungry caterpillars: Get out now to locate and properly dispose of spongy moth egg masses, produced by adult moths last summer.

Continue reading “Now Is Time To Seek Out Spongy Moth Egg Masses”

Make Plans Now To Fight Spongy Moth In 2025

A photo showing large egg masses on a tree at the Kettle Moraine State Forest-Southern Unit in 2021.

Large egg masses are seen on a tree at the Kettle Moraine State Forest-Southern Unit in 2021. / Photo Credit: Bill McNee, Wisconsin DNR

By Bill McNee, DNR Forest Health Specialist, Oshkosh
Bill.McNee@wisconsin.gov or 920-360-0942

Part Two of a report on spongy moth in Wisconsin in 2024 and 2025. Part One was published in December.

The Wisconsin Department of Natural Resources (DNR) is encouraging property owners to examine their property for spongy moth egg masses and plan for action this spring if needed. Each spongy moth egg mass contains hundreds of eggs that will hatch into hungry, leaf-eating caterpillars this spring. Large numbers of these invasive caterpillars can be a tremendous nuisance that may cause tree mortality.

Continue reading “Make Plans Now To Fight Spongy Moth In 2025”

It’s A Good Time To Work On Oak Trees

A person prunes a tree during the winter months.

Winter is an ideal time to perform pruning and trimming work on oak leaves. / Photo Credit: Wisconsin DNR

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

Winter is an ideal time to perform trimming, cutting and brush removal work on and near oak trees.

For one thing, it’s a low-risk period for the trees to be infected with oak wilt, a fungal disease spread by beetles. When a red oak is infected with oak wilt, it will die that year; the disease also stresses trees in the white oak group, often fatal with bur oaks and swamp white oaks.

Continue reading “It’s A Good Time To Work On Oak Trees”

2024 Forest Health Annual Report Published

The cover of the Wisconsin Department of Natural Resources' 2024 Forest Health Annual Report.

The cover of the Wisconsin Department of Natural Resources’ 2024 Forest Health Annual Report. / Graphic Credit: Wisconsin DNR

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

Hot off the digital presses, the Wisconsin Department of Natural Resources (DNR) has made its 2024 Forest Health Annual Report ready for review and download.

This year’s edition contains 58 pages of reporting on forest health issues throughout Wisconsin, detailing methods employed by the DNR and other agencies to control pests and diseases.

Continue reading “2024 Forest Health Annual Report Published”

Tree Disease Maps Have Migrated

The Wisconsin web map for Heterobasidion root disease, available through ArcGIS Online.

The Wisconsin web map for Heterobasidion root disease, available through ArcGIS Online. / Map Credit: Paul Cigan, Wisconsin DNR

By Paul Cigan, DNR Forest Health Specialist, Hayward
Paul.Cigan@wisconsin.gov or 715-416-4920

The Wisconsin Department of Natural Resources (DNR) Forest Health program hosts two interactive web maps on its webpage:

Heterobasidion Root Disease

Oak Wilt Seasonal Harvesting Opportunities

Continue reading “Tree Disease Maps Have Migrated”

McNee To Speak At Green Bay Conference

Photo showing a few periodical cicadas trying to hitch a ride on the T-shirt of Bill McNee, the Wisconsin Department of Natural Resources Forest Health specialist for northeast Wisconsin, in 2024 at Big Foot Beach State Park in Lake Geneva.

A few periodical cicadas try to hitch a ride on the T-shirt of Bill McNee, the Wisconsin Department of Natural Resources forest health specialist for northeast Wisconsin, at Big Foot Beach State Park in Lake Geneva in 2024. / Photo Credit: Wisconsin DNR

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

Bill McNee, the Wisconsin Department of Natural Resources (DNR) forest health specialist for the Southeast region, will give a public presentation on Saturday, Jan. 25, at the Green Bay Winter Landowner Conference.

Continue reading “McNee To Speak At Green Bay Conference”

2024 Spongy Moth Review

By Bill McNee, DNR Forest Health Specialist, Oshkosh;
Bill.McNee@wisconsin.gov or 920-360-0942

A tree shows high numbers of spongy moth caterpillars, though the majority of the caterpillars have been killed either by virus (hanging in an inverted V) or fungus (hanging in a stretched line, head down). The virus and fungus helped to quell a potential outbreak in many areas of the state in 2024.

A tree shows high numbers of spongy moth caterpillars, though the majority of the caterpillars have been killed either by virus (hanging in an inverted V) or fungus (hanging in a stretched line, head down). The virus and fungus helped to quell a potential outbreak in many areas of the state in 2024. / Photo Credit: Bill McNee, Wisconsin DNR

As the 2023 spongy moth season ended, there were hopes for a return to colder and wetter conditions in 2024 so that the spongy moth outbreak would decline or even come to an end.

What wound up happening in Wisconsin was the “lost winter,” the warmest since recordkeeping began in 1895. Given this warmth, there were concerns that the widespread spongy moth outbreak would continue for a third consecutive summer, with good caterpillar survival, ongoing defoliation and high rates of tree mortality in already stressed forests.

Continue reading “2024 Spongy Moth Review”