Taking action

Treat Your Valuable Ash Trees Against Emerald Ash Borer This Spring

By Bill McNee, 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.

Woodpecker damage during the winter is often the first sign that an ash tree is infested. The birds remove pieces of bark while feeding on EAB larvae inside the tree. Insecticide treatment of infested ash trees is more likely to be successful if the trees have low or moderate levels of woodpecker damage.

Now is a good time to consider insecticide protection, because the treatments are typically done between mid-April and mid-May. Ash (in the genus Fraxinus) is the only type of tree that needs protection against EAB. Mountain ash and prickly ash do not need protection because the insect does not attack them.

Ash tree branch in West Allis has been damaged by woodpeckers. Sections of bark are missing, exposing the tree’s light brown wood.

This ash tree branch in West Allis has been damaged by woodpeckers feeding on EAB larvae beneath the bark.
Photo: Bill McNee, Wisconsin DNR.

Continue reading “Treat Your Valuable Ash Trees Against Emerald Ash Borer This Spring”

DNR Foresters Partner with LEAF Program to Update Forester Activity Guide

In 2008, LEAF, Wisconsin’s K-12 Forestry Education Program, created a Forester Activity Guide. The intent of the guide was to help foresters lead age-appropriate, interactive, hands-on classroom programs for students in grades K-8 with a minimum amount of advanced preparation. The guide was promoted to foresters throughout Wisconsin and even included as part of programming during new forester orientation.

Front page of the Forester Activity Guide. Credit: LEAF

In fall 2021, LEAF staff, working with Kirsten Held, determined that an update to the guide was overdue. To be certain a new guide would meet the needs of current foresters, LEAF sought input from professionals around the state who have both field experience and an enthusiasm for working with students.

The following DNR Division of Forestry staff partnered with LEAF to create a new and improved Forester Activity Guide: Brooke Ludwig, Eau Claire; Steven Kaufman, Oconto Falls; Kara Oikarinen, Washburn; Scott Mueller, Medford; Sarah Ward, Montello; and Brian Wahl, Fitchburg.

The new Forester Activity Guide builds upon the goals set for the original K-8 guide by including more opportunities for outdoor learning around themes that foresters are frequently asked about: What Do Foresters Do?; Caring for the Forest; Forest Products & Benefits, Tree Planting and Natural Restoration and Fire.

All activities include tips for modifying lessons to urban settings and suggestions on how to use the lessons with learners from grades K-12. Lessons in the new guide all have slideshow presentations that foresters can use if their visits must take place in an indoor setting and require even less advanced preparation than lessons for the original guide. Continue reading “DNR Foresters Partner with LEAF Program to Update Forester Activity Guide”

Make Your 2023 Spongy Moth Treatment Plans Early

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

As long as weather conditions are favorable for the spongy moth* (formerly known as gypsy moth) population, the current outbreak is predicted to continue and spread to other parts of Wisconsin in 2023. Property owners are encouraged to examine susceptible host trees (including oak, birch, crabapple, aspen and willow) and plan ahead.

Spongy moth egg masses on a tree next to a penny for size comparison.

Spongy moth egg masses are tan-colored lumps that are larger than a penny, about the size of a nickel or quarter. Photo: Wisconsin DNR

Continue reading “Make Your 2023 Spongy Moth Treatment Plans Early”

Harvest Timing Affected By Spongy Moth

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

Numerous spongy moth egg masses on a bur oak in southern Waukesha County, November 2022.

Numerous spongy moth egg masses on a bur oak in southern Waukesha County, November 2022. Photo: Bill McNee, Wisconsin DNR.

Forest managers planning silvicultural treatments in spongy moth susceptible stands (containing a large proportion of host species including oak, birch, aspen and basswood) are encouraged to annually conduct egg mass surveys in the few years prior to the scheduled treatment to predict if heavy defoliation is likely. The results may indicate that management activities should be altered or delayed until an outbreak has ended. At present, stands that were heavily defoliated in 2022 or are predicted to be heavily defoliated in 2023 are most likely to need a management delay or alteration.

It is recommended that a time interval be left between a stress agent (such as heavy defoliation or significant drought) and stand thinning so that the trees can recover from pre-existing stress before being subjected to additional stress. One growing season is a common interval for healthy stands that are not being subjected to drought or other stresses. A longer interval is suggested if the tree stress has been more severe or if the stand was not healthy and vigorously growing at the time of defoliation. The same interval is probably appropriate regardless of which stress agent is the pre-existing one. A protective aerial spray may prevent tree stress from defoliation but is usually not economically viable due to the high cost of an aerial treatment.

Continue reading “Harvest Timing Affected By Spongy Moth”

Attention Hunters: Help Slow The Spread Of Invasive Species!

By Jaqi Christopher, DNR Forest Invasive Plant Specialist, Rhinelander, Jacquelyn.christopher@wisconsin.gov

With the dropping temperatures and changing leaves, it’s beginning to feel like fall hunting season.

While you travel across the state to check hunting spots or tend to food plots, look for unwanted hitchhikers on your clothing and equipment. Seeds from invasive plants like garlic mustard, tansy and spotted knapweed can travel far distances in the mud on your vehicle, trailer, ATV, shoes and clothing.

Two women on either side of a mud-covered black truck with gear and a black dog in tow prepare for a day of duck hunting.

Inspecting and cleaning vehicles, equipment, gear and pets before and after recreating can help slow the spread of invasive species. Photo credit: Wisconsin DNR

Continue reading “Attention Hunters: Help Slow The Spread Of Invasive Species!”

Moving Firewood Can Spread Invasive Species

An image of an insect walking away from burning firewood in a forest with the caption, “Buy it where you burn it.”

Don’t Move Firewood, The Nature Conservancy

October is Firewood Month! Help prevent the spread of invasive insects and diseases by buying firewood where you burn it.

Firewood Scout can help you find local firewood for sale.

See the DNR website for more information on invasive species and forest health. Continue reading “Moving Firewood Can Spread Invasive Species”

Tree City USA Applications Open!

The Arbor Day Foundation’s Recertification application portal for this year is now open and available. The Arbor Day Foundation’s Tree City USA program is working to help grow the urban tree canopy in Wisconsin. With more than 200 designated communities, almost 60% of Wisconsinites live in a Tree City USA community.

Tree City USA communities show a strong commitment to growing and maintaining a healthy tree canopy. To receive the recognition, communities must:

  • maintain a tree board or department
  • have a community tree ordinance
  • spend at least $2 per capita on urban forestry
  • celebrate Arbor Day.

Continue reading “Tree City USA Applications Open!”

DNR Leads Milwaukee Heat Mapping Project

Mitchell Park Domes. Credit: WDNR

Wisconsin DNR urban forest assessment specialist Dan Buckler had been monitoring weather forecasts for a month, waiting for just the right blisteringly hot day to launch a much-anticipated Milwaukee heat island mapping project. He’d been laser-focused on getting the one-day blitz in the books, and July 21 turned out to be go time.

The urban heat island effect explains the phenomenon that densely developed urban spaces are warmer than outlying places due to man-made surfaces (such as asphalt) absorbing and reradiating heat through the day and night. Trees are one method of reducing urban temperatures by providing shade and by putting more water vapor into the air via evapotranspiration.

Continue reading “DNR Leads Milwaukee Heat Mapping Project”

Submit an Urban Forestry Council Award Nomination Today!

The Wisconsin Department of Natural Resources (DNR) is accepting nominations for the Wisconsin Urban Forestry Council 2023 Awards until October 31, 2022.

The Wisconsin Urban Forestry Council is responsible for advising the DNR on the best ways to preserve, protect, expand, and improve Wisconsin’s urban and community forest resources. Every year, the council presents annual awards to outstanding individuals, organizations, communities, and tribes that further urban forestry in Wisconsin. The awards are announced each year at the annual Wisconsin Urban Forestry Conference and are presented to winners in their community. Continue reading “Submit an Urban Forestry Council Award Nomination Today!”

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”