DNR Debuts Fact Sheet On White Grubs

Posted on by akabelowsky
Closeup photo showing a white grub in topsoil, feeding on a root.

A white grub feeds on a root. / Robert L. Anderson, USDA Forest Service, Bugwood.org

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

White grubs, the larvae of Wisconsin’s native May/June beetles (Phyllophaga spp.), can cause significant damage to forest plantings.

To help those who plan to plant seedlings and saplings, the Wisconsin Department of Natural Resources’ (DNR) Forest Health team has produced a fact sheet on white grubs, aimed specifically at forest plantings.

Continue reading “DNR Debuts Fact Sheet On White Grubs” →

Yellow Needles On White Pine This Spring

Posted on by akabelowsky
A closeup photo showing current-year white pine needles emerging among yellow needles that show spots and banding.

Current-year white pine needles emerge among yellow needles that show spots and banding. / Photo Credit: Linda Williams, Wisconsin DNR

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

In North Central Wisconsin, some Eastern white pine had needles that turned a bright yellow color in early June, then quickly dropped from the trees by the end of June.

These trees will now look rather thin throughout the summer, until new foliage can fully expand and start to fill in the crown. Most damage has been noted in Oneida and Vilas counties, with scattered instances in other counties. Continue reading “Yellow Needles On White Pine This Spring” →

Wild Cucumber Will Catch Your Attention

Posted on by akabelowsky
A photo showing star-shaped leaves, pale flowers and cucumber fruit, all characteristics of wild cucumber.

Star-shaped leaves, pale flowers and cucumber fruit, all characteristics of wild cucumber. / Photo Credit: Bugwood.org

By the Wisconsin Department of Natural Resources

Plants that are pokey, viny or quick to spread across the landscape sometimes seem alarming when you discover them in your backyard or woods, or even when you spot them along the highway.

Wild cucumber has all these characteristics, and its growth rate has been quite prolific in some parts of Wisconsin again this year. But all of this is not as ominous as it seems.

Continue reading “Wild Cucumber Will Catch Your Attention” →

Winsome Fly Biocontrol Slows Japanese Beetle

Posted on by akabelowsky
A closeup photo showing Winsome fly eggs on three Japanese beetles, including a mating pair with a female Japanese beetle below the male.

Winsome fly eggs are found on three Japanese beetles, including a mating pair (with a female Japanese beetle shown below the male). One or more eggs are laid on each beetle; eggs are nearly always laid just behind the head. The Winsome fly prefers to lay eggs on female Japanese beetles. / Photo Credit: Jacques Lasnier, Quebec, Bugwood.org

By Bill Hutchison, Department of Entomology
University of Minnesota
Hutch002@umn.edu

The Winsome fly (Istocheta aldrichi (Mesnil)), part of the Tachinidae family, is a parasitoid of the invasive pest Japanese beetle (Popillia japonica).

A parasitoid is an insect whose larvae develop in or within a host insect of a different species, eventually killing it.

The Winsome fly was introduced in 1923 in New Jersey as a biological control agent of the Japanese beetle, six years after the Japanese beetle was accidentally introduced in the United States. Since then, the Winsome fly has become established in the Northeastern states and Quebec and Ontario in Canada.

Continue reading “Winsome Fly Biocontrol Slows Japanese Beetle” →

Woolly Elm Aphid Causes Elm Leaves To Curl

Posted on by akabelowsky
Closeup photo of a group of elm leaves that show varying levels of wrinkling and curling, due to feeding by wooly elm aphids on the underside of the leaves.

A group of elm leaves shows varying levels of wrinkling and curling, due to feeding by wooly elm aphids on the underside of the leaves. / Photo Credit: Linda Williams, Wisconsin DNR

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

Woolly elm aphids (Eriosoma americanum) are a minor pest of American elm. The aphids’ feeding causes leaves to curl at the edges and develop a characteristic wrinkled appearance.

Uncurling the leaves exposes many pale gray aphids on the underside of the leaves, which are protected by the rolled leaf.

Continue reading “Woolly Elm Aphid Causes Elm Leaves To Curl” →

2026 Urban Forestry Grants Announced

Posted on by janness

By Nicolle R. Spafford, DNR Urban Forestry Grants Manager; Nicolle.Spafford@wisconsin.gov or 715-896-7099

Beginning July 1, 2025, cities, villages, towns, counties, tribes and 501(c)(3) nonprofit organizations in –or conducting their projects in – Wisconsin can apply for a regular or startup 2026 Wisconsin Department of Natural Resources (DNR) Urban Forestry grant. The total 2026 available funding is $559,680, with a possible release of $139,920 of catastrophic storm reserve to fund a second round in March 2027. Continue reading “2026 Urban Forestry Grants Announced” →

Please Submit Trees Planted This Spring!

Posted on by janness

By Dan Buckler, DNR Urban Forest Assessment Specialist; Daniel.Buckler@wisconsin.gov or 608-445-4578

When your newly planted trees are getting comfortable in their new homes, you’ve pulled the splinters from your hands and you find yourself at a desk asking yourself, “What now?”, we have an answer for you.

Please take a moment and record your trees in the Wisconsin Tree Planting Survey. Those submissions will then appear on the Tree Planting Map and be tallied toward the state’s pledge to the Trillion Trees Initiative. Governor Tony Evers signed the pledge to protect and restore Wisconsin’s rural and urban forests by planting 100 million trees in Wisconsin by 2030. Continue reading “Please Submit Trees Planted This Spring!” →

Anthracnose Infecting Hardwood Leaves

Posted on by janness

By Michael Hillstrom, DNR Forest Health Specialist; Michael.Hillstrom@wisconsin.gov
and Abby Krause, DNR Urban Forestry Coordinator; Abigail.Krause@wisconsin.gov

Oak leaves infected with anthracnose.

Anthracnose is a common disease of hardwood trees during cool, wet spring seasons. Some parts of Wisconsin have been cooler and wetter than others this spring, so anthracnose damage may be patchy.

Ash, maple, white oak, sycamore and walnut are the most commonly impacted tree species. Each species has its own species of anthracnose that infects it, but if weather conditions are right, then we tend to see damage on multiple species. Continue reading “Anthracnose Infecting Hardwood Leaves” →

Resources For Storm-Damaged Trees

Posted on by janness

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

With recent storms passing through Wisconsin, communities may still be working on clean-up. Depending on the intensity of the storms and the condition of the trees, damage from high winds, heavy rainfall, hail and lightning can be quite severe. Cracked or broken branches, trunk damage and root failure are some of the main concerns, but also the risk and liability of damage to people and property. Continue reading “Resources For Storm-Damaged Trees” →

Why Don’t All Trees Leaf Out At The Same Time?

Posted on by janness

By Elton Rogers, DNR Urban Forestry Coordinator; Elton.Rogers@wisconsin.gov or 414 294-8675

Photo credit: Mike Wendt

Spring is my absolute favorite time of the year. The reemergence of life is all around us, and the smell of fresh rain accompanies the sights and sounds of spring. The birds are scouring the soil for fresh insects to eat, the frogs are croaking away in the swamps and the bees buzz freely from plant to plant. Along with these sights and sounds of spring, another incredible transformation is occurring on our largest and longest-lived organisms in the landscape, trees. Continue reading “Why Don’t All Trees Leaf Out At The Same Time?” →