Forest Health News

‘In The Weeds’ With Invasives Tech

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

Photo of popular garden plants including tulips and daffodils.

While not native to the Midwest, popular garden plants such as tulips and daffodils do not spread outside of gardens or cause harm, therefore they are not invasive. / Photo Credit: Lesley Ingram, Bugwood.org

As the conversation around invasive plants grows, it’s easy to get “stuck in the weeds” when it comes to invasive terminology.

A simple Google search of “invasive plant” will produce a variety of definitions, bringing in technicalities or muddying your understanding with each new idea of what invasive means. Continue reading “‘In The Weeds’ With Invasives Tech”

Millions Of Cicadas Preparing To Emerge

By Michael Hillstrom, Forest Health Specialist, Fitchburg;
Michael.Hillstrom@wisconsin.gov

Closeup photo of a periodical cicada, showing its black body and orange-colored wing veins and legs.

Closeup of a periodical cicada, showing its black body and orange-colored wing veins and legs. / Photo Credit: Ward Upham, Kansas State University, Bugwood.org

2024 will be a big year for periodical cicadas (Magicicada spp.).

For the first time since 1803 — when Thomas Jefferson was president — 13-year Brood XIX and 17-year Brood XIII cicadas will co-emerge in the millions.

If you want to observe this spectacle, you can see the Brood XIII cicadas in southern Wisconsin. Expect to see and hear them in June, and bring your ear protection because some of the louder choruses of males can reach 90 decibels.

Continue reading “Millions Of Cicadas Preparing To Emerge”

Emerald Ash Borer Spreads Through The North

By Paul Cigan, DNR Forest Health Specialist, Hayward;
https://dnr.wisconsin.gov/topic/foresthealth/staff, 715-416-4920

This winter, the spread and impact of emerald ash borer (EAB) have been confirmed in several new northern townships in previously invaded counties.

These include Marengo (Ashland County); Gordon, Hawthorne and Oakland (Douglas County); Cadott and Colburn (Chippewa County) and Balsam Lake and St. Croix Falls (in Polk County).

Continue reading “Emerald Ash Borer Spreads Through The North”

Feeding Aphids Cause Spruce To Wilt

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

Have you ever wondered just how much sap can be sucked out of a tree by aphids?

Aphids insert their piercing, sucking mouthparts into needles, twigs or bark, depending on the species of aphid.

Once their mouthparts are inserted, they begin to suck sap and will excrete excess moisture as small droplets of water called honeydew.

Continue reading “Feeding Aphids Cause Spruce To Wilt”

Time for Spongy Moth Treatment Plans

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

A photo showing numerous spongy moth egg masses on a bur oak in Walworth County.

Numerous tan-colored spongy moth egg masses on a bur oak in Walworth County. / Photo Credit: Bill McNee, Wisconsin DNR

The Wisconsin Department of Natural Resources (DNR) encourages property owners to examine their trees for spongy moth egg masses and determine whether control measures are needed this spring.

Spongy moths thrive in warm and dry weather. Even if weather conditions are more typical this spring and summer, the current spongy moth outbreak — which defoliated a state-record total of 373,000 acres of woodland last year — will likely continue and spread.

Continue reading “Time for Spongy Moth Treatment Plans”

Invasive Species Find The Spotlight In February

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

Graphic showing home page for NISAW.org-slash-forest, titled Invasive Species Are Damaging Our Forests

One focus for policy development during NISAW 2024 is forest health and invasive plants. NAISMA has created an easy way to contact your elected officials to let them know you support the Invasive Species Prevention and Forest Restoration Act. / Image Credit: NAISMA.org

While February in Wisconsin may bring to mind snow-covered ground and little new plant growth, it’s quite a big month for action in the invasive species world. The last week of February brings National Invasive Species Awareness Week (NISAW), an international event that focuses on legislation, policies and funding for the prevention and management of invasive species.

Continue reading “Invasive Species Find The Spotlight In February”

Squirrel Damage To Maple Trees Showing Up Earlier This Winter

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

Photo of a maple tree with some bark removed by squirrel feeding.

Squirrels have stripped off the bark of this maple tree to get at the sweet cambium layer under the bark. / Photo Credit: Linda Williams, Wisconsin DNR

Typically in the spring, squirrels can cause damage to maple trees by removing bark from branches and the main stem after the trees have been frozen all winter and the weather starts to warm up. This fall, before the January cold spell, temperatures had warmed up by mid-November and remained warm throughout December.

As a result, starting in late November fresh squirrel damage was being noted on some scattered maples in north central Wisconsin. Damage progressed throughout December and some trees have more than half of the bark removed from branches and the main stem. The sight of scattered bits of bark around the base of these trees is another sign of squirrel activity.

Continue reading “Squirrel Damage To Maple Trees Showing Up Earlier This Winter”

Woodpecker Damage On Ash Trees May Indicate Emerald Ash Borer

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

Photo showing woodpecker damage on an ash tree trunk, an early sign the tree might be infested with emerald ash borer.

Woodpecker damage is an early sign an ash tree might be infested with emerald ash borer. / Photo Credit: Wisconsin DNR

The Wisconsin Department of Natural Resources (DNR) encourages property owners to watch for woodpecker damage to their ash trees this winter. If damage is found, property owners should make plans to take action in the spring.

Woodpecker damage, often called “flecking,” happens when birds peck away some of a tree’s bark to access the larvae underneath. Flecking is a common early sign that an ash tree might be infested with emerald ash borer (EAB), an invasive insect. EAB is the most damaging threat to Wisconsin trees, killing more than 99% of the untreated ash trees it infests.

Continue reading “Woodpecker Damage On Ash Trees May Indicate Emerald Ash Borer”

Leafminer Creates Green Bay Packers Colors On Aspen Leaves

Photo of an aspen leaf that fell in the fall showing a “green island” due to leafminer feeding.

An aspen leaf that fell in the fall showing a “green island” due to leafminer feeding. / Photo Credit: Linda Williams, Wisconsin DNR

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

Most aspen leaves that fell this fall were a beautiful yellow gold color, but every so often some could be found that were yellow with a green strip on them. Were the aspen trees supporting the Green Bay Packers? No. The green stripe was an indication of the presence of a tiny leafmining caterpillar.

Leafminers are tiny caterpillars that live and feed within a leaf. These tiny caterpillars may produce blotch mines or serpentine mines that create lines on the leaf.

Continue reading “Leafminer Creates Green Bay Packers Colors On Aspen Leaves”