Forest Health News

Pink-Striped Oakworm Population Remains Low

Posted on by akabelowsky
Photo of a pink-striked oakworm caterpillar on a hand.

This large caterpillar, a pink-striped oakworm, has great camouflage and blends in with oak twigs very well. / Photo Credit: Linda Williams, Wisconsin DNR

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

Pink-striped oakworm is a native fall defoliator. Fall defoliators affect the health of trees less than defoliators that occur in the spring.

Although literature states that high populations of this caterpillar can create significant defoliation, no defoliation was noted in the area this caterpillar was observed in Oneida County.

Continue reading “Pink-Striped Oakworm Population Remains Low” →

Not-So-Notorious Native Buckthorn

Posted on by akabelowsky
Photo of alder-leaved buckthorn, a native species in Wisconsin.

The native alder-leaved buckthorn is much smaller than its invasive counterparts and prefers wet areas such as fens. / Photo Credit: Wisconsin DNR

By Mary Bartkowiak, DNR Invasive Plant Program Coordinator, Rhinelander Service Center;
Mary.Bartkowiak@wisconsin.gov or 715-493-0920
and Erika Segerson-Mueller, DNR Invasive Plant Program Specialist, Oshkosh Service Center;
Erika.Segersonmueller@wisconsin.gov or 715-492-0391

Most of the rather frequent buzz about buckthorn revolves around the two non-native, invasive types: common and glossy. The Wisconsin Department of Natural Resources (DNR) reminds the public that while these aggressive plants and serial invaders are common in Wisconsin forests, there is also a benign and native buckthorn that gets much less attention.

Many people are surprised to learn about this small shrub that has eluded notoriety, unlike its close relatives. Native buckthorn, also known as alder-leaved buckthorn (Rhamnus alnifolia), is a demure shrub that doesn’t grow much taller than 3 feet and prefers wet areas with calcium in the soil.

Continue reading “Not-So-Notorious Native Buckthorn” →

Time To Seek Out Spongy Moth Egg Masses

Posted on by akabelowsky

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

Photo of spongy moth egg masses on a tree.

Three spongy moth egg masses are found on a tree branch at Kettle Moraine State Forest Southern Unit in Walworth County. / Photo Credit: Bill McNee, Wisconsin DNR

The Wisconsin Department of Natural Resources (DNR) is encouraging property owners to seek out and dispose of spongy moth egg masses, which were produced by adult moths during the summer.

Each spongy moth egg mass contains hundreds of eggs that will hatch into hungry, leaf-eating caterpillars in the coming spring. Large numbers of these invasive caterpillars can be a tremendous nuisance that may cause tree mortality.

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

Beware Of Bittersweet In Fall Decor

Posted on by akabelowsky
Photo of round leaf bittersweet berries

The berries of round leaf bittersweet (Celastrus orbiculatus) grow in clusters at each leaf axil. The highly invasive nature of this plant makes it unsuitable for use in fall decorations. / Photo Credit: Chris Evans, University of Illinois, Bugwood.org

By Erika Segerson-Mueller, Invasive Plant Program Specialist, Oshkosh Service Center;
Erika.Segersonmueller@wisconsin.gov or 715-492-0391

When temperatures begin to cool and back-to-school sales emerge, our thoughts turn to pumpkin spice, sweater weather and all things fall décor.

But as you gear up for spooky season this year, the Wisconsin Department of Natural Resources (DNR) reminds you to beware of using invasive plants in your decorations.

Continue reading “Beware Of Bittersweet In Fall Decor” →

Aphids Make Sticky Situation For Oak, Beech Trees

Posted on by akabelowsky

 

Photo of Myzocallis oak aphids on a leaf, with an adult at the left.

Myzocallis aphids feed on the top side of oak leaves. An adult is pictured on the left. / Photo Credit: Linda Williams, Wisconsin DNR

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

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

Aphids — and the honeydew they produce — have made their mark on trees in Wisconsin during 2023.

Midway through the summer, oak trees in areas of Vilas and Oneida counties were buzzing with activity. During September, beech trees in eastern Wisconsin became busy with a different species of aphid.

A look at the two situations:

Continue reading “Aphids Make Sticky Situation For Oak, Beech Trees” →

Look For Spongy Moss Egg Masses

Posted on by akabelowsky

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

Photo of spongy moth egg masses on a tree.

Three spongy moth egg masses are found on a tree branch at Kettle Moraine State Forest Southern Unit in Walworth County. / Photo Credit: Bill McNee, Wisconsin DNR

Now that spongy moth egg laying is complete for 2023, it’s a good time to look for and dispose of the egg masses produced by adult moths over the past two months.

Spongy moth egg masses are tan-colored lumps about the size of a nickel or quarter, and can be found on trees, buildings and other outdoor objects. They may also be found in protected places such as firewood piles and birdhouses.

Continue reading “Look For Spongy Moss Egg Masses” →

Emerald Ash Borer Detected In Rusk County

Posted on by akabelowsky

By Paul Cigan, DNR Forest Health Specialist, Hayward
Paul.Cigan@wisconsin.gov or 715-634-9232

Photo of an emerald ash borer on a tree

Emerald ash borer was detected in Rusk County in northwest Wisconsin in late July, making it the 69th of Wisconsin’s 72 counties that have confirmed presence of the invasive insect. / Photo Credit: Paul Cigan, Wisconsin DNR

The emerald ash borer (EAB) has been detected for the first time in Rusk County, making it the 69th of Wisconsin’s 72 counties to determine the presence of the invasive insect.

On July 25, Wisconsin Department of Natural Resources Forest Health staff investigated a report of several ash trees with woodpecker flecking and branch dieback in a village park along Railroad Avenue in the Village of Sheldon.

Continue reading “Emerald Ash Borer Detected In Rusk County” →

Don’t Spread Invasive Plants This Hunting Season

Posted on by akabelowsky

Erika Segerson-Mueller, DNR Invasive Plant Program Specialist, Oshkosh Service Center Erika.SegersonMueller@wisconsin.gov or 715-492-0391

Photo of a hunter walking through a field.

Whether you are headed out to a tree stand in your favorite local forest or a duck blind on the shore of your nearby pond, you can take a few easy precautions to help minimize the spread of invasive plants in your favorite hunting spots. / Photo Credit: NAISMA.org

Heading out to your tree stand or hunting blind this fall? Avoid adding invasive species to your hunting party by taking a few simple steps to help protect your woods.

Non-native invasive plants often outcompete native plants in forest environments, degrading diversity and destroying wildlife habitat. Invasive plants can replace local forest species and may interfere with or decrease tree regeneration. They may take over woodlands, prairies and wetlands, and many provide ideal habitats for pests that harm wildlife and people alike.

Continue reading “Don’t Spread Invasive Plants This Hunting Season” →

Balsam Fir Mortality Similar To 2018 And 2019

Posted on by akabelowsky

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

Photo of balsam fir tree prematurely turning brown and red.

Scattered balsam fir trees in the Northwoods have suddenly turned brown and red this spring. / Photo Credit: Linda Williams, Wisconsin DNR

Scattered balsam fir trees in some areas of northern Wisconsin have suddenly turned rusty red to brown and are dying. These trees are not being impacted by spruce budworm and typically die with a full complement of needles.

The symptoms resemble what was observed in 2018 and 2020. So far, the number of trees being reported is smaller than what was seen in 2018 or 2020. Reports are still coming in, but they seem to be concentrated in northern areas of the state where we had extensive snowfall in late winter.

Continue reading “Balsam Fir Mortality Similar To 2018 And 2019” →

Pine Bark Adelgids Infest White Pines

Posted on by akabelowsky
Photo of pine bark adelgids covered in white, waxy fluff on a white pine tree.

Pine bark adelgids covered in white, waxy fluff on a white pine tree. / Photo Credit: Wisconsin DNR

Michael Hillstrom, DNR Forest Health Specialist, Fitchburg
Michael.Hillstrom@wisconsin.gov

Pine bark adelgids are tiny, aphid-like insects that suck the sap of white pines. The bugs protect themselves from predators with a fluffy, white wax covering. Pine bark adelgids generate concern when thousands of them gather on white pines to feed, making the pine bark appear covered with sap.

Continue reading “Pine Bark Adelgids Infest White Pines” →