Protect Oaks During Spring Clean-up

Posted on by akabelowsky

By Paul Cigan, DNR plant pest and disease specialist, Paul.Cigan@wisconsin.gov or 715-416-4920

An oak tree with branches trimmed

To prevent the spread of often-fatal oak wilt disease, do not prune, cut or wound oaks from April through July. Photo: Wisconsin DNR

With the arrival of spring, the Wisconsin Department of Natural Resources (DNR) recommends protecting oaks from the often-fatal oak wilt disease by refraining from pruning, cutting or injuring oak trees from April through July.

The highest risk period for oak wilt introduction to a new site is in spring and early summer. Pruning and cutting oaks exposes living tree tissue beneath the bark to potential infection. The disease rapidly kills trees in the red oak group and weakens those in the white oak group.

Sap-feeding beetles spread the disease between oaks by carrying oak wilt spores from infected trees or firewood to fresh, exposed tree wounds. Healthy oaks and freshly cut oak stumps can become infected as quickly as 15 minutes after a wound is made from a pruning cut or broken branch.

Continue reading “Protect Oaks During Spring Clean-up” →

First Recovery of Emerald Ash Borer Enemy Made

Posted on by akabelowsky

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

Map showing Spathius Galinae recovery in Manitowoc County

Sites where EAB biological controls have been recovered as of March 2023. The Spathius galinae recovery site is indicated by a red star. Blue dots show Tetrastichus planipennisi recovery sites. Municipal EAB detections are in green. Map: Wisconsin DNR

Two adult wasps, collected last December as pupae from an emerald ash borer (EAB) gallery at Kiel Marsh State Wildlife Area in Manitowoc County, have recently been identified as Spathius galinae.

This find marks the first time that S. galinae has been recovered in Wisconsin, confirming that the adult wasps released at this site over the last few years were able to attack EAB larvae and reproduce successfully. The “EAB wasps” were released as biological controls to help reduce EAB populations over the long term.

This wasp species has a longer ovipositor than the other EAB larval parasitoid currently released in Wisconsin (Tetrastichus planipennisi), allowing S. galinae to attack EAB larvae that are beneath thicker bark.

Spathius galinae was first released in Wisconsin in 2016, and approximately 1,000 of this species were released at Kiel Marsh in 2019 and 2020. Recovery surveys are conducted several years after initial releases, giving the wasps time to reproduce and spread. Continue reading “First Recovery of Emerald Ash Borer Enemy Made” →

Aerial Spraying Set For Four State Sites

Posted on by akabelowsky

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

Spray aircraft used in spongy moth control

Spray aircraft used in spongy moth control. Photo: Bill McNee

At a suitable time between early May and early June, an airplane will spray parts of four DNR properties to reduce the population of spongy moth caterpillars (formerly known as gypsy moth). Treatment dates will depend on weather conditions and caterpillar development.

This year’s high populations threaten to strip trees of their leaves and possibly kill high-value trees at these properties.

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Heterobasidion Root Disease Approaches

Posted on by akabelowsky

By Alex Feltmeyer, Forest Health Specialist, Plover, Alexandra.Feltmeyer@wisconsin.gov or 715-340-3810

A Heterobasidian root disease fruiting body at the base of a white pine sapling

A Heterobasidion root disease fruiting body is found at the base of a white pine sapling in the understory. Photo: Wisconsin DNR Forest Health

Heterobasidion Root Disease (formerly annosum root rot or Fomes root rot) is a serious disease of conifers that causes reduced height, shoot and diameter growth along with thin and yellowish/red foliage, ultimately causing mortality.

The disease becomes established in a new stand when spores of the fungus land on freshly cut stumps made by any forest management that creates cut stumps. After the disease becomes established, it spreads underground through root systems into adjacent trees. In this way, we often find pockets or groups of trees in various stages of decline.

Movement through the root systems contributes to significant spread throughout stands of conifers, impacting the regeneration of conifers within these pockets.

Mortality usually starts occurring three to eight years after a thinning operation. During this time, perennial fruiting bodies of the fungus begin to develop around the base of cut stumps or dead trees.

Continue reading “Heterobasidion Root Disease Approaches” →

Hungry Squirrels Find Trees Tasty

Posted on by akabelowsky

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

Maple branches with light colored areas where squirrels removed bark.

Squirrels remove the bark of maples, leaving bright bare spots. Photo: Wisconsin DNR

It’s the time of year when we start to see scattered maple trees stripped of their bark. Squirrels cause this damage — which can be limited to a few small areas the size of a tennis ball or can extend to cover many feet of branches or the main stem.

The squirrels are going after the cambium layer, just under the bark, that tastes slightly sweet from the sap. Smooth bark is easier for squirrels to chew, so young trees or branches with thin bark are likelier to be stripped than those with older, furrowed bark.

At this time of year, the pale wood of the branches that have had the bark stripped off is nearly white; later in the season, this wood will darken or even turn black with sooty mold. This type of feeding can remove enough bark to girdle the branches or the main stem, causing the tree to die from that point to the end of the branch.

Branches that are not completely girdled will continue to grow, and callus tissue will begin to grow over the wounds. If branches are nearly girdled, they may leaf out this spring and then suddenly wilt and die as hot weather hits because the tree can’t deliver enough water to keep those leaves alive. Continue reading “Hungry Squirrels Find Trees Tasty” →

Lab Assistant Departs

Posted on by akabelowsky

By Art Kabelowsky, DNR Forest Health Outreach Specialist, Arthur.Kabelowsky@wisconsin.gov or 608-335-0167

Another photo will be hung on the unofficial “Wall of Fame” bulletin board inside the Department of Natural Resources Forest Health Lab in Fitchburg.

Ethan Wachendorf, who joined DNR as a laboratory assistant on May 23, 2022, departed on Thursday, March 23, to pursue a Master of Science in plant pathology at Michigan State University in East Lansing.

Outgoing Forest Health lab assistant Ethan Wachendorf at a microscope

Ethan Wachendorf

Wachendorf started as a summer lab assistant, but at the start of 2023 became a dual LTE, working as the lab assistant. The Colorado native joined the DNR after earning a bachelor’s degree in government (with a minor in biology) from Lawrence University in Appleton.

Wachendorf said he was drawn to Michigan State for post-graduate studies after working with Dr. Monique Sakalidis, who runs the university’s forest pathology lab.

“I’ll be working on oak wilt testing and management techniques, such as herbicide, fungicide, rapid response and the way the trees change physiologically,” Wachendorf said.

He will work full-time at the Michigan State lab until the fall semester, when he will split his time between lab duties and classwork.
His Wisconsin impressions include how “Midwest nice” the people are, how good the beer is, and how cold it gets — and stays — in the Badger state.

Seedlings Still Available For Spring 2023 Planting

Posted on by Kirsten Held

Winter hasn’t quite let loose its snowy grip from the Wilson State Nursery fields in Boscobel, but spring will soon be here, and the reforestation program staff are readying themselves to harvest seedlings from the cool, moist soil. It won’t take long for the frost to leave the ground.

For those who have spent parts of the winter planning to improve their properties, the Wisconsin DNR’s reforestation program has plenty of seedlings available to create and enhance wildlife habitat, stabilize the soil, block winter wind and snow and provide a future shady spot to sit. Continue reading “Seedlings Still Available For Spring 2023 Planting” →

Eight Applicants Receive DNR Urban Forestry Grants In Second Round Of Funding

Posted on by patricialindquist

The DNR Urban Forestry Grant program awarded $108,220 to eight Wisconsin communities for urban forestry projects during the second round of our 2023 funding. Most of the funding ($104,920) was originally reserved for the Catastrophic Storm Grant program but was not needed through the winter months. The rest of the funding ($3,300) came from underspent grants.

The following communities will receive the funds:

  • Village of Allouez, $17,783.00
  • Town of Beloit, $11,804.80
  • Forest County Forestry & Recreation, $3,007.38
  • Heckrodt Wetland Reserve, $5,581.97
  • City of Kaukauna, $25,000.00
  • Mequon Nature Preserve, $7,250.23
  • City of Oshkosh, $25,000.00
  • Urban Tree Alliance, $12,792.62

Continue reading “Eight Applicants Receive DNR Urban Forestry Grants In Second Round Of Funding” →

2023 Urban Forestry Council Award Winners

Posted on by patricialindquist

By: Kirsten Biefeld, Urban Forestry Outreach Specialist

The Wisconsin Urban Forestry Council recently announced their annual awards honoring those dedicated to protecting, preserving and increasing the number of trees that line city streets, fill community parks and beautify neighborhoods throughout the state.

The Wisconsin Urban Forestry Council advises the Wisconsin Department of Natural Resources (DNR) on managing urban and community forest resources.

“Wisconsin plays a critical role in conservation, especially when it comes to trees! These awards honor individuals, organizations and communities for their hard work and dedication to trees and the benefits they provide,” said Linda Cadotte, Wisconsin Urban Forestry Council Award Committee Chair. “It’s an honor to learn more about the incredible work happening around our state that helps support healthy community forests.”

Urban Forestry Council Award Winners

The 2023 Urban Forestry Award winners. From left to right: John Wayne Farber, Leadership Award; John Gall, Lifetime Achievement Award; Cory Gritzmacher, receiving the Innovation Award on behalf of the Mequon Nature Preserve. Photo credit: Wisconsin DNR

Continue reading “2023 Urban Forestry Council Award Winners” →

More Than 1,000 Wisconsin Municipalities Now Known To Have Emerald Ash Borer

Posted on by patricialindquist

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

In 2022, the number of municipal emerald ash borer (EAB) detections in Wisconsin crossed the 1,000 milestone. The 1,000th municipality (town, village or city) to have an EAB detection was the Town of Lincoln in Adams County on May 19. At the end of the year, EAB was known to be in 1,109 municipalities, up 23% from a year earlier.

Graph showing cumulative number of Wisconsin municipal emerald ash borer detections by year.

Cumulative number of Wisconsin municipal EAB detections by year. Graph: Bill McNee, Wisconsin DNR.

Continue reading “More Than 1,000 Wisconsin Municipalities Now Known To Have Emerald Ash Borer” →