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2019 First Downs for Trees

Green Bay Packers and DNR staff plant a ceremonial Sterling Linden tree in Titletown to help offset the Green Bay Packer’s carbon footprint produced by traveling to away games. Trees naturally sequester carbon dioxide, providing a long-term solution to the problem because trees sequester more and more carbon as they grow larger. This marks the 9th year of the Packer’s First Downs for Trees (FDFT) Program which has planted 5,144 trees to date throughout Brown County.

DNR Secretary Cole, DNR staff and former Packers Johnnie Gray and Gerry Ellis planting a tree.

DNR Secretary Cole, DNR staff and former Packers Johnnie Gray and Gerry Ellis planting a tree.

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Wisconsin DNR Urban Forestry News subscriber survey

Introduction

Providing timely and relevant information to the Wisconsin urban forestry community is a key role of the Wisconsin DNR Urban Forestry program. One of the ways in which this goal manifests itself is through a monthly newsletter received by 5,555 subscribers (May 2019). In order to ensure that the newsletter content is relevant and timely, the Urban Forestry program surveyed subscribers in spring 2019. Results are shown and interpreted below and suggestions made for future newsletter editions. Continue reading “Wisconsin DNR Urban Forestry News subscriber survey”

Professionally-designed HRD guidelines now available

Cover page of HRD guidelines documentThe professionally-designed version of the Heterobasidion root disease (HRD) stump treatment guidelines is now posted on the DNR’s HRD webpage. The revised stump treatment guidelines, developed to reduce the risk of introduction and spread of HRD in Wisconsin, were implemented January 1, 2019. The content is the same as the guidelines that were approved last year, but this document has a layout that is much more user-friendly. Explore the new look of the HRD guidelines.

 

Watch for signs of oak wilt

Linda Williams, forest health specialist, Woodruff, Linda.Williams@wisconsin.gov, 920-360-0665 

Trees in the red oak group (those with points on their leaves) that were infected with the oak wilt fungus this spring will rapidly drop their leaves from July to September and be dead by fall. This wilting and dropping of the green leaves happens quickly. Once it starts, the tree will drop most of its leaves within just a few weeks.

Tree dying from oak wilt with rapidly dropping leaves.

Tree dying from oak wilt with rapidly dropping leaves. The tree was injured in May, attracting the beetles that help spread the fungus, and the tree was dead by the end of the year. Photo was taken in August.

Red oak leaf from infected tree. Leaves are often green at the base, with the outer portions of the leaf appearing water-soaked or brownish.

Red oak leaf from infected tree. Leaves are often green at the base, with the outer portions of the leaf appearing water-soaked or brownish.

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Ants, aphids and sooty mold on white pine

Linda Williams, forest health specialist, Woodruff, Linda.Williams@wisconsin.gov, 920-360-0665

Ants, aphids, and sooty mold can cause stunting and death of young white pines, but fortunately there are some steps you can take to protect your trees from these pests.

Ants guard aphids from predators as they feed. In exchange, the ants collect the sweet honeydew excreted by the aphids.

Ants (upper right) guard aphids from predators as they feed. In exchange, the ants collect the sweet honeydew excreted by the aphids.

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Watch for cherry scallop shell moth defoliation

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

Cherry scallop shell moth, a native defoliator, is back again in Jefferson and Walworth counties. Several residents recently reported large numbers of moths in areas that have experienced multiple years of defoliation by this insect.

Eggs laid by those moths are expected to hatch soon, and the emerging caterpillars will begin feeding on cherry tree foliage. Hopefully, populations of egg-parasitizing natural enemies will be high enough this year to provide relief to stressed trees.

Early instar caterpillars on cherry leaf.

Early instar caterpillars on cherry leaf.

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Heavy seed crop leads to sparse-looking trees

Todd Lanigan, forest health specialist, Eau Claire, Todd.Lanigan@wisconsin.gov, 715-839-1632

You may have noticed some of the elms and maples had a lot of brown in them at the end of May and early June. Some elms and maples produced a lot of seed this spring, which reduced the amount of energy available for producing leaves. With fewer leaves and more of the brown, papery seeds, the trees can take on a thin, brown appearance.

Heavy seed years can occur for many reasons. It happens naturally from time to time and it can also be stimulated by environmental stressors. A couple of examples of environmental stressors are: excessive moisture, winter injury and frost damage to roots.

The cause of this year’s heavy seed production is anyone’s guess. There does not appear to be a common pattern between the affected trees to indicate whether it was simply a normal heavy seed year or related to an environmental factor.

 

Browning on tamarack needles

Linda Williams, forest health specialist, Woodruff, Linda.Williams@wisconsin.gov, 920-360-0665

Defoliation from larch casebearer (Coleophora laricella) is showing up in some areas of northeast and northcentral Wisconsin. The defoliation is patchy and of moderate intensity, resulting in trees with various degrees of browning due to the insect’s feeding habits. Some appear pale yellow or brown throughout the crown while others only have partial browning.

Defoliated larch needles turn yellow then brown.

Defoliation by larch casebearer will cause needles to turn yellow then brown. Trees will usually send out more needles and be green again by mid-summer.

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Branch flagging caused by jack pine resin midge

Paul Cigan, forest health specialist, Hayward, Paul.Cigan@wisconsin.gov, 715-416-4920

Jack pine shoots are flagging over a large area of northern and west central Wisconsin this summer due to feeding injury from the jack pine resin midge. Symptoms include scattered dead branch tips and pitch masses on terminal buds and on twigs where larvae feed.  

Jack pine with dead branch tips caused by jack pine resin midge. Photo: Paul Cigan.

Jack pine with dead branch tips. Photo: Paul Cigan.

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