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A Wonderful Winter Display: Phomopsis Galls

Posted on by akabelowsky
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” →

Frost’s Bite: How Do Insects Survive Winter?

Posted on by akabelowsky
An emerald ash borer larva overwinters by curling into a J shape inside a channel in an ash tree in Brookfield in 2019.

An emerald ash borer larva overwinters by curling into a J shape inside a channel in an ash tree in Brookfield in 2019. / Photo Credit: Bill McNee, Wisconsin DNR

By Michael Hillstrom, DNR Forest Health Specialist, Fitchburg

Michael.Hillstrom@wisconsin.gov

As winter’s chill persists, Wisconsin Department of Natural Resources (DNR) Forest Health staff members are often asked how cold it needs to get to kill insects, especially invasives.

The answer varies from species to species, but many insects are well adapted to dealing with freezing winter temperatures. Some, such as monarchs, avoid the issue and migrate south for the winter. Others, such as multicolored Asian ladybeetles, annoy us with their presence in our homes and offices as they try to avoid the cold until spring.

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Spring Dreaming: Keep Invasive Plants Out Of Garden Plans

Posted on by akabelowsky
Originally planted as a garden ornamental, Japanese barberry can quickly escape cultivation and invade Wisconsin’s woodlands.

Originally planted as a garden ornamental, Japanese barberry can quickly escape cultivation and invade Wisconsin’s woodlands. / Photo Credit: Wisconsin DNR

By Wisconsin DNR

Even though winter’s grip has taken hold in Wisconsin, many gardeners are already thinking ahead to the next spring planting season.

While dreaming of spring blooms and designing your next garden or landscape layout, be on the lookout for invasive plants that may try to weed their way into your plans.

Continue reading “Spring Dreaming: Keep Invasive Plants Out Of Garden Plans” →

Now Is Time To Seek Out Spongy Moth Egg Masses

Posted on by akabelowsky
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.

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What Are Those White Fluffies On Trees?

Posted on by akabelowsky
Lots of beech scale, covered in white wool, makes this tree’s bark look fluffy.

Lots of beech scale, covered in white wool, makes this tree’s bark look fluffy. / Photo Credit: Linda Williams, Wisconsin DNR

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

Last month, we introduced readers to the woolly alder aphid, which is easier to spot in the winter as the insects congregate on alder branches and grow strands of white, waxy material to cover themselves for winter.

But there are other white, fluffy things that you might notice on tree bark or branches as well.

Beech scale, the insect associated with beech bark disease, is covered in white wool and remains on the tree throughout the winter. In areas with high beech scale populations, the beech trees can be so white with insects that the bark looks white, like a birch.

Continue reading “What Are Those White Fluffies On Trees?” →

New Tree Canopy Resources Released

Posted on by janness

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

Urban Tree Canopy (UTC) assessments using aerial or satellite imagery have been one of the primary ways people estimate the extent of urban forests across an area of interest, whether it be a single park, a streetscape or a whole community.

Two recently released UTC resources are ready for use by Wisconsin communities and urban forestry practitioners. The first, TreeCanopy.us, is a mapping application that shows UTC and other land cover in urban areas across the country for 2017 and 2022. It also shows changes in canopy cover between those five years. Continue reading “New Tree Canopy Resources Released” →

International Society Of Arboriculture Credential Renamed

Posted on by janness

The International Society of Arboriculture (ISA) Certified Arborist Municipal Specialist® credential will now be called ISA Certified Urban Forest Professional.

New Logo, Same Benefits

As an ISA Certified Urban Forest Professional, you continue showing the public, employers and peers that you have achieved the critical knowledge and skills needed to manage trees as a community asset providing societal benefits in an urban forest context. Continue reading “International Society Of Arboriculture Credential Renamed” →

Winter Tree ID

Posted on by janness

How do you learn to identify trees in the middle of a Wisconsin winter when most of the leaves are on the ground?

LEAF’s Winter Tree Key follows the dichotomous process of our regular tree key but uses detailed illustrations of buds, twigs and features other than leaves for identification. The key also includes an illustrated glossary defining the specific vocabulary involved in this process. Winter tree identification can be a bit more demanding. Continue reading “Winter Tree ID” →

It’s A Good Time To Work On Oak Trees

Posted on by akabelowsky
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.

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Woodpecker Flecking On Ash Means EAB

Posted on by akabelowsky
Photo showing that woodpecker flecking on green ash and white ash, from birds feeding on emerald ash borer larvae, will often be extensive and very noticeable.

Woodpecker flecking on green ash and white ash, from birds feeding on emerald ash borer larvae, will often be extensive and very noticeable. / Photo Credit: Linda Williams, Wisconsin DNR

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

Ash trees that are flecked by woodpeckers will have the outer layers of their bark chipped off by the birds. Woodpeckers do this to punch through the remaining bark more easily to get at the tasty emerald ash borer (EAB) larvae living there.

Flecking usually starts at the top of the tree, providing a sure sign that insects are under the bark. Although the problem could be caused by ash bark beetles, the more common culprit is EAB.

Continue reading “Woodpecker Flecking On Ash Means EAB” →