Taking action

Look For Spongy Moth Egg Masses – Larger Outbreak Possible in 2023

By: Bill McNee, DNR Forest Health Specialist, Oshkosh

bill.mcnee@wisconsin.gov or 920-360-0942

Three tan-colored spongy moth egg masses on a single tree branch in Walworth County.

Three spongy moth egg masses on a branch in Walworth County. Photo Credit: Bill McNee, Wisconsin DNR

Now that spongy moth* (formerly known as gypsy moth) egg laying is complete for 2022, it’s a good time to look for and dispose of 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 are found on trees, buildings and other outdoor objects. They may also be found in protected places such as firewood piles and birdhouses. Newly produced egg masses will feel firm and appear darker in color than older egg masses, which appear faded, feel spongy and do not contain viable eggs. The current-year egg masses will not hatch until next spring.

In 2022, Wisconsin’s spongy moth population grew for a third consecutive summer due to favorable weather conditions and limited caterpillar mortality from diseases. The outbreak was most dramatic in opposite ends of the state. In southern and southeast Wisconsin, several thousand oak-dominated acres were heavily defoliated and very large numbers of property owner reports were received by DNR staff. In Bayfield County, about 80,000 acres of rural defoliation was reported from aspen-dominated forests. Smaller patches of defoliation were also reported from several other counties. Continue reading “Look For Spongy Moth Egg Masses – Larger Outbreak Possible in 2023”

April Showers Bring May Garlic Mustard

By Brenna DeNamur, DNR Forest Health Outreach Specialist, Madison, Brenna.DeNamur@wisconsin.gov; Jaqi Christopher, DNR Forest Invasive Plant Specialist, Rhinelander, Jacquelyn.Christopher@wisconsin.gov; & Mary Bartkowiak, DNR Forest Invasive Plant Coordinator, Rhinelander, Mary.Bartkowiak@wisconsin.gov

Spring is here! Invasive plants, like garlic mustard, are often among the first green life to emerge in the new season.

A dense population of garlic mustard carpets a forest floor.

Garlic mustard is an invasive plant that appears early in spring. Photo: Wisconsin DNR

Continue reading “April Showers Bring May Garlic Mustard”

Arbor Day Celebrates 150 Years

In 1854, J. Sterling Morton, a prominent newspaper editor and publisher, moved from Detroit to what is now Nebraska. He and other pioneers noticed a need for trees, which could act as windbreaks to stabilize the soil and give shade from the sun. Morton planted many trees around his own home and encouraged others to do the same.

On Jan. 4, 1872, he proposed a holiday to plant trees on April 10 that year. This was known as “Arbor Day.” 

Individuals and counties that planted the most trees that day received prizes. About one million trees were planted in Nebraska on the first Arbor Day. Over the next 150 years, Arbor Day celebrations have spread to all 50 states and around the world.

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USDA Biological Control Facility Seeks Ash Trees To Battle Emerald Ash Borer

USDA staff cut a ‘bark window’ in green ash to uncover signs of emerald ash borer.

Emerald ash borer (EAB) is an invasive insect from Asia first introduced into the United States in 2002. Since its discovery, EAB has caused tens of millions of ash trees to die and decline. Today, the U.S. Department of Agriculture (USDA) uses ash trees against the pest to help preserve and protect the tree species. They are asking Wisconsin landowners for their help.

Wisconsin landowners have donated live, infested ash trees to USDA’s EAB biological control program. The staff will then use the wood to cultivate EAB’s natural enemies and release them in Wisconsin and 28 other EAB-infested states. The biocontrol staff will need more ash trees to continue producing and releasing these stingless wasps that attack and kill EAB and are hoping more Wisconsin residents will consider donating their ash trees this year.

Continue reading “USDA Biological Control Facility Seeks Ash Trees To Battle Emerald Ash Borer”

Emerald Ash Borer Found In Bayfield County

By Paul Cigan, DNR Forest Health Specialist

Paul.Cigan@wisconsin.gov or 715-416-4920

Emerald ash borer (EAB) has been discovered in Bayfield County for the first time in both the city of Bayfield and Bayview township to the south. This marks the 63rd out of Wisconsin’s 72 counties to have an EAB discovery since its initial detection in 2008.

Dead white ash with woodpecker damage in a park

Figure 1: First known infested ash tree in Bayfield County with characteristic woodpecker damage (i.e., flecking).
Photo: Wisconsin DNR

Several white ash trees (Fig 1.) were observed in and around a roadside park in the city of Bayfield, and larval specimens were subsequently lab-confirmed. In Bayview, a black ash swamp had several infested black ash (Fig 2). 

After introduction, EAB populations remain low for at least several years as most larvae in newly infested, healthy ash require two years to complete their life cycle. The abundance of healthy ash at each site suggests EAB populations have remained low since their introduction at least three years ago. However, EAB will kill ash more quickly as beetle numbers mount and more larvae transform from egg to adult in a single year. Unfortunately, many ash in the area are expected to die within four to seven years based on detection-to-impact timeframes observed from the Superior and Duluth area and research conducted in midwestern states. Continue reading “Emerald Ash Borer Found In Bayfield County”

Career Opportunities At The DNR: Become Our Next Urban Forestry Council Liaison And Outreach Specialist

The Wisconsin Department of Natural Resources (DNR) is hiring a Limited-Term Employment position – Urban Forestry Council Liaison and Outreach Specialist located at our central office in Madison, Wisconsin.

This dual LTE appointment is made of two 20-hour positions for an expected work schedule of 40 hours per week. The intention is to hire one candidate for both positions.

Applications are due April 27, 2022. Keep reading for more information on the positions and how to apply.

Continue reading “Career Opportunities At The DNR: Become Our Next Urban Forestry Council Liaison And Outreach Specialist”

Protect Your Valuable Ash Trees Against Emerald Ash Borer

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

Property owners with healthy, valuable ash trees are encouraged to treat them with insecticide this spring to protect against emerald ash borer (EAB). The pest is currently the most damaging threat to trees in Wisconsin, killing more than 99% of the ash trees it infests.

Ash tree branch in West Allis has been damaged by woodpeckers. Sections of bark are missing or have been flecked away.

This ash tree branch in West Allis has been damaged (“flecked”) by woodpeckers feeding on EAB larvae under the bark.
Photo: Bill McNee, Wisconsin DNR

Continue reading “Protect Your Valuable Ash Trees Against Emerald Ash Borer”

One Last Chance To Treat Or Remove Spongy Moth Egg Masses; DATCP Slow-The-Spread Aerial Treatments Announced

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

Three tan-colored lumps about the size of a nickel or a quarter are spongy moth egg masses on the underside of a pine branch in Walworth County.

Three spongy moth egg masses on the underside of a pine branch in Walworth County.
Photo: Bill McNee, Wisconsin DNR

Spongy moth* (formerly known as gypsy moth) egg masses typically begin to hatch in April as temperatures warm. Now is a great time to inspect your trees for egg masses and treat or remove any masses within reach. Each mass that hatches may produce up to 1,000 leaf-eating caterpillars.

Populations of spongy moths increased in 2020 and 2021 due to favorable weather conditions. This winter’s temperatures have not been cold enough to cause heavy egg mortality. A large rise in caterpillar numbers can be expected in 2022 if weather conditions are warm and dry over the next few months.

Continue reading “One Last Chance To Treat Or Remove Spongy Moth Egg Masses; DATCP Slow-The-Spread Aerial Treatments Announced”

EAB Identified In Lincoln County For The First Time, Continues Spread Into Northern Wisconsin

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

Emerald ash borer (EAB) continues to spread into areas of Northern Wisconsin and was detected for the first time in Lincoln County, in the Town of Harrison and the City of Tomahawk. EAB was first identified in Wisconsin in 2008, only 14 years ago. It is now in 62 of Wisconsin’s 72 counties.

S-shaped markings in an ash tree trunk where a hatchet has removed the bark.

S-shaped galleries under the bark of this ash were created by EAB larvae. You can also see epicormic branches (water sprouts) coming out of the trunk. These are a sign of significant stress in the tree. Photo Credit: Wisconsin DNR

Continue reading “EAB Identified In Lincoln County For The First Time, Continues Spread Into Northern Wisconsin”