Care for your woods

My Wisconsin Woods Values Your Woodlands

YOUR WOODS can be a source of food for your family.
OR your favorite hunting ground.
OR even create a source of income!

Whatever you value most, your woods are your gateway to the outdoors. Whether you own several hundred acres or just enough to take a short walk, sustainably managing your woodland is important. The best part is you don’t have to do it alone. My Wisconsin Woods, a public, private partnership serving woodland owners across the state, has launched a comprehensive landowner portal to connect you with natural resource professionals, forestry events in your area, and free information and materials. Recently released is a video series for landowners who are curious about what forestry benefits might exist or have nagging concerns. This series was made possible through the generous support of the Ruffed Grouse Society and David Moore with production and content provided by the Department of Natural Resources, Aldo Leopold Foundation and Driftless Area Land Conservancy.

So let’s go exploring …

May 18: WWOA Open Woods events across Wisconsin

Are you a woodland owner who would like to learn more about caring for your woodlands and keeping it healthy? Perhaps you are thinking of purchasing woodlands?  This day is for you!

YOU are invited to join Wisconsin Woodland Owners Association’s (WWOA) 40th year celebration of educating and assisting Wisconsin’s private woodland owners by attending one of their Open Woods events on Saturday, May 18, 2019. WWOA members around the state will celebrate by opening their private woodlands to the public and hosting a variety of family-friendly events to showcase how they have improved their land through forest management.

The list of event hosts and activities on the WWOA website continues to be updated, so check back often.​ Bring your family, friends, and neighbors to enjoy a walk in the woods or special activity.

Each site will offer a variety of fun events such as walks with the hosts and forester or other natural resource professionals to showcase how the woodlands have been cared for or tentative projects on the land. Other entertainment may include children’s activities with Smoky Bear, crafts, natural bird feeders, wildflower seed bombs, and tree/plant/wildlife identification and exhibits from various nonprofit organizations and agencies. Many locations are also offering snacks and refreshments or encouraging participants to bring a picnic lunch to enjoy in the woods.

Learn more about caring for your woods at www.wisconsinwoodlands.org

Invasive insects threaten Wisconsin hemlock

By Mike Hillstrom, forest health specialist, Fitchburg, Michael.Hillstrom@wisconsin.gov, 608-513-7690

Two invasive insects, hemlock woolly adelgid (HWA) and elongate hemlock scale (EHS), pose serious threats to Wisconsin’s hemlock trees. Although neither insect is established in Wisconsin, both insects have been found in recent years on infested nursery stock or live tree material that was shipped into the state. Fortunately, these introductions were detected and the plant material destroyed. But with HWA established in hemlock stands of several Michigan counties along Lake Michigan, natural spread to Wisconsin is anticipated.

Because of the risk, forest health staff from the Department of Natural Resources (DNR) and the Department of Agriculture, Trade and Consumer Protection (DATCP) are conducting surveys for early detection of these pests. Both pests could appear in many settings including urban and rural forests, yard trees and holiday tree plantations so everyone has a role to play in looking for these pests and reporting what they see.

HWA and EHS both feed on tree needles with sucking mouthparts. When populations are large enough, this feeding causes excessive fluid and nutrient loss, leading to declining tree health. Both insects can be found together on infested hemlock trees.

A group of adult hemlock woolly adelgid covered in white waxy filaments feeding on hemlock needles.

Characteristic white wax coating of adult hemlock woolly adelgid.

There are a few key ways to spot these insects. HWA is most obvious in winter when white, wax-covered adults are present. You may also see hemlock foliage turning gray-green in color as tree health declines. Adult EHS have a waxy cover and feed on the underside of hemlock, spruce and fir needles. Damage from EHS appears as yellow banding on needles. Crowns appear progressively thinner as infested needles die and fall off prematurely. Both insects also have tiny immature crawlers that may be seen moving on infested trees.

Tiny adult scales protected with a waxy cover feed on needles causing yellow banding.

Adult elongate hemlock scale and yellow needle banding (Credit: WI DATCP).

If you suspect you’ve found either HWA or EHS, please report it immediately to your local DNR forest health specialist. For more information about HWA, visit the DNR and DATCP webpages. To learn about EHS, visit the DATCP webpage.

Make trees mean more

Spring is upon us and that means the tree planting season is too. Trees are vital to our environments; they provide individuals and communities with clean air, clean water, reduced cooling costs, safer neighborhoods, and a place to play and gather. But trees provide much more than that, they can help show how much we care for others, a beautiful living reminder of the legacy of a person. Arbor Day is this month, and it is the perfect time to plant a tree and illustrate our feelings for others. Continue reading “Make trees mean more”

Protect oaks from oak wilt by waiting to prune

By Don Kissinger, urban forester, 715-348-5746, don.kissinger@wisconsin.gov and Paul Cigan, forest health specialist, 715-416-4920, paul.cigan@wisconsin.gov

To protect oak trees from the often-fatal oak wilt disease, don’t prune, cut or injure oak trees from April through July. 

Pruning and cutting oaks in spring and early summer leaves them vulnerable to oak wilt, which rapidly kills trees in the red oak group and weakens those in the white oak group. Any damage during this time, including broken branches caused by storms, exposes living tree tissue beneath the bark and provides an opportunity for the oak wilt fungus to infect the tree.

Sap-feeding beetles introduce the disease by carrying oak wilt spores from infected trees or firewood to fresh wounds. Healthy oaks can become infected in as little as 15 minutes after the creation of a wound. 

Sap-feeding beetle on diseased oak tree in Sawyer County.

Sap-feeding beetle on diseased oak tree in Sawyer County.

The trees most likely to die from oak wilt infection are in the red oak group, including northern pin oak, northern red oak, red oak and black oak. The white oak group is more likely to survive infection and includes bur oak, swamp white oak, white oak and English oak.

Tree paint or wound dressing is not normally recommended on pruned or wounded surfaces, but for damaged oaks an immediate light application of these products may be the only defense against oak wilt infection from April through July.

Pruning in spring can be damaging to any deciduous tree because their energy reserves are low as they produce new buds and leaves following the winter months. In general, the best time to prune is in winter when trees are dormant. 

As of January 31, oak wilt has been found in all Wisconsin counties except Ashland, Iron, Forest, Taylor, Door, Kewaunee, Calumet and Manitowoc counties. Several of these counties contain the highest abundance of healthy and productive oak forests in the state. Taking recommended precautions will help keep them that way for years to come.

Oak wilt and other diseases move easily on or in firewood logs year-round, so keeping firewood local, or purchasing Wisconsin-certified firewood, is another important component of protecting trees and keeping forests healthy. Visit the DNR firewood page for more information and a directory of certified firewood vendors.

More information, including a recently released oak wilt video, is available at the DNR oak wilt page. Additional information about proper pruning techniques is available from community foresters or through DNR resources such as this tree pruning poster

Don’t change EAB plans due to cold weather

By Bill McNee, forest health specialist, Oshkosh, bill.mcnee@wisconsin.gov, 920-360-0942

The recent frigid temperatures in late January and early February are likely to kill many overwintering emerald ash borer (EAB) larvae, but the tree-killing pest isn’t going away. The insulating properties of tree bark keep the larvae warmer than the outdoor air temperature, and wind chills do not affect the larvae because they are sheltered. The pest is also adapted to subzero temperatures based on its native range in eastern Asia where cold winters are common.

Prepupal larva seen during post-polar vortex sampling to assess larval mortality.

Overwintering prepupal larva, from February 2019 in Brookfield, WI.

On the morning of January 31, many parts of Wisconsin had low air temperatures between -30 and -35 degrees F. In places where it was this cold, scientific studies predict that most EAB larvae will be killed. Where low temperatures were between -20 and -30, larval mortality is likely to be lighter. Overwintering larvae were examined about 1 week after the cold snap in Brookfield (Waukesha County), where the low was -26, and few of the larvae were observed to have physical signs of freezing damage. Many of the larvae began moving within three days of being brought indoors. However, physical damage to the larvae may not yet be apparent, and normal-looking larvae may ultimately die from the cold temperatures.

Populations of the pest are likely to rebound, since each female beetle that emerges this summer will lay as many as 200 eggs. It is not currently known if larval mortality will significantly delay ash tree decline and mortality, although this may occur in areas that experienced the lowest temperatures. A cold spell in early 2014, that was not quite as cold, had no noticeable impacts on EAB spread or ash decline/mortality in areas known to be heavily infested.

The introduced biological controls of EAB, commonly known as “EAB wasps,” are at least as cold-tolerant as EAB. It is expected that these wasps will persist in and around release sites and continue parasitizing EAB eggs and larvae.

Forestry experts do not recommend changing EAB management plans solely due to the cold weather.

  • Continue to look for EAB in ash trees. Woodpecker damage is a good sign that an ash tree is infested with EAB or other pests.
  • Insecticide treatment of high-value ash trees near known infestations should be continued this spring.
  • Don’t delay tree removals or timber harvests that are already scheduled. Giving non-ash tree species more time to grow means that the future impacts of EAB will be reduced.
  • Continue planting non-ash tree species.
  • To help slow the spread of EAB, review firewood rules in Wisconsin. Buy firewood in the local area where you plan to burn it or buy Wisconsin-certified firewood that has been treated to eliminate pests. Certified firewood is often available at DNR-managed properties or you can buy from an independent certified firewood dealer.

Additional information about emerald ash borer, insecticide treatments and forest management can be found online at www.emeraldashborer.wi.gov.

Accounting for trees in stormwater models

Accounting for Trees in Stormwater Models is a resource to share with stormwater engineers. The paper is intended to help the stormwater engineering community more easily account for trees in runoff and pollutant load calculations and incorporate them into stormwater management strategies. It summarizes existing hydrologic and hydraulic models that can be applied at the site and small watershed scales to account for the stormwater benefits of conserving existing trees and/or planting new trees. The paper also includes examples of specific techniques to modify stormwater models to account for urban tree benefits, as well as associated resources and tools for estimating the hydrologic benefits of trees in the urban landscape. Continue reading “Accounting for trees in stormwater models”

Does your community have forest-friendly development practices?

Not every city in Wisconsin has a municipal code or ordinance that includes trees, and even then, those that do have codes may not have forest-friendly ones. A new resource has been created and has taken care of the hard work of determining if your city’s codes are forest-friendly; and if they are not, the resource provides advice on how trees can be more welcome in your neighborhoods. Continue reading “Does your community have forest-friendly development practices?”

Phillips High continues evaluating community trees

Phillips High School students are showing the value of trees in their community. For the past three years the students have been inventorying the trees in the community. Over those years the project has continued to grow each year, from collecting data on trees to identifying planting sites, and now building community awareness by putting price tags on trees. Continue reading “Phillips High continues evaluating community trees”

Public comment period for HRD treatment guidelines revision closes October 16

A fruiting body of Heterobasidion irregulare at the base of a pine tree.

By Kyoko Scanlon, forest pathologist, Fitchburg. Kyoko.Scanlon@wisconsin.gov; 608-235-7532

Wisconsin DNR is seeking public comments on a proposed revision to preventative treatment guidelines for Heterobasidion root disease (HRD). Stand-level HRD treatment guidelines were originally released in 2013. A DNR technical team and stakeholder advisory committee proposed a revised version using recent research findings, operational experience, and economic considerations.

The draft document and information about the public comment process can be found at  https://dnr.wi.gov/news/input/Guidance.html#open through Tuesday, October 16, 2018. All comments must be submitted by that date.