Wisconsin DNR Forest Health 2019 Annual Report

Wisconsin DNRForest Health2019 Annual ReportAsh killed by emerald ash borer, wetforest converting to marsh.

Table of ContentsWisconsin DNR Forest Health Staff . 1District staff . 1Statewide staff . 2Staff update . 3Strategic Direction of the Forest Health Program . 3The Forest Resource in Wisconsin. 4Outreach and education . 5Exotic Species Issues . 6Beech bark disease . 6Jumping worms (Amynthas spp.) . 6Emerald ash borer (EAB, Agrilus planipennis) . 7Distribution of EAB in Wisconsin . 7Damage from EAB in Wisconsin . 9Biological control of EAB .11Gypsy moth (Lymantria dispar) .13Heterobasidion root disease (HRD, Heterobasidion irregulare) .14Research on HRD .14Invasive plant suppression program .15Amur cork tree (Phellodendron amurense) .15Oak wilt (Bretziella fagacearum) .16History in Wisconsin .16Prevention of infection and spread .17In woodlots .17Along powerlines, roads and in communities .18Control .18White pine bast scale (Matsucoccus macrocicatrices) and the canker disease (Caliciopsispinea).19Hardwood issues .20Bur oak blight (Tubakia iowensis) .20Other oak health issues .20Botryosphaeria .20Leaf fungal pathogens .20

Galls on leaves and twigs .20Mature bur and white oak decline and mortality .20Oak twig pruner .21Two-lined chestnut borer .21Phytoplasma (Candidatus Phytoplasma fraxini) .21Conifer Issues .22Eastern larch beetle (Dendroctonus simplex) .22Pine wood nematode .22Rhizosphaera on spruce .23State nursery studies .23Asymptomatic infection by Diplodia sapinea in state nursery stock.23Survey of galls on jack pine seedlings at the Wilson Nursery .23Fumigant study – preliminary report .24Spruce budworm (Choristoneura fumiferana) .25Abiotic Issues .25Acknowledgements .27

Wisconsin DNR Forest Health StaffDistrict staffLinda WilliamsForest health specialistNortheast zone, exandra FeltmeyerForest health specialistCentral zone, vPaul CiganForest health specialistNorthwest zone, Hayward715-416-4920Paul.Cigan@wisconsin.govTodd LaniganForest health specialistWest central zone, Eau Claire715-839-1632Todd.Lanigan@wisconsin.govMike HillstromForest health specialistSouth central zone, ovBill McNeeForest health specialistSoutheast zone, Oshkosh920-360-0942Bill.McNee@wisconsin.govFigure 1. Locations and zones of forest healthspecialists as of Dec. 2019.1

Statewide staffBecky GrayForest health program team govScott SchumacherPlant pest and disease sconsin.govAndrea Diss-TorranceInvasive forest insects wisconsin.govBernie WilliamsInvasive plants and earthworm isconsin.govKyoko ScanlonForest onsin.govMark GuthmillerLab guerite RappOutreach/communications nsin.govPhyllis ZiehrClerical sin.govMary BartkowiakInvasive plants isconsin.govVacantForestry invasive plants coordinator2

Staff updateIn 2016, Mark Guthmiller retired after 26 yearsas forest health specialist for the southwesterncounties, but this summer he rejoined the teamas pathology lab assistant. We were alldelighted to welcome him back: his cheerfulcompetency and historical knowledge of forestpathogens in WI were a wonderful return to theteam.Strategic Direction of the Forest Health ProgramThe Forest Health Program provides technical expertise in the prevention, detection,assessment, management and monitoring of invasive plants, insects and diseases that damagetrees and forests, and the benefits they provide. The program assists public and privatelandowners in their efforts to minimize the establishment and adverse impacts from invasiveplants and destructive forest insects and diseases. Strategic planning for Forest Health hasfocused efforts on management guidelines, historical data analysis in the annual report and keyintra-agency partnerships.In 2019, two revised guidelines were implemented on January 1st: “Guidelines for stumptreatment to reduce the risk of introduction and spread of Heterobasidion root disease inWisconsin” and “Emerald Ash Borer Silviculture Guidelines.” Trainings on the guidelines wereconducted around the state throughout the year for DNR staff and external partners.Reducing the spread of invasive species on Wisconsin DNR managed lands is a top priority.The Wisconsin State Parks welcome over 14 million visitors a year, and sometimes invasivespecies hitch a ride. The Forest Health Program partnered with the DNR Bureau of Parks andRecreation on four specific projects in 2019. Invasive Amur cork trees were removed from theMacKenzie Education Center. Hazard tree training was restructured to better serve Parksemployees. Emerald ash borer biological controls were released at Peninsula and KohlerAndrae state parks as part of the integrated pest management of the destructive beetle. EABManagement Plans were developed in partnership with Governor Dodge and Wildcat Mountainstate parks.

The Forest Resource in WisconsinFigure 2. Wisconsin forest cover map. Source: WISCLAND land cover, Wisconsin Dept. ofNatural Resources, 2017 (latest version).Wisconsin’s forests are critical for providing wildlife habitat, clean air and water, reducingerosion, and improving the quality of life in urban and rural areas. Forests are also important tothe economy of Wisconsin for wood products, recreation and tourism. Current information onthe forest resource in Wisconsin is available at dnr.wi.gov.4

The area of forestland in Wisconsin has steadily increased in recent decades and currentlystands at approximately 17 million acres up by 500,000 acres since 2016 (Figure 3). This is anincrease of 1.3 million acres since 1996 and 2.3 million acres since 1983. Wisconsin now hasmore forested area than at any time since the first forest inventory was conducted in 1936. Over46% of the state’s land area is forested, primarily in the northern and western areas of the state.Wisconsin’s forests are composed primarily of hardwood species. The most abundant foresttypes are oak-hickory at 26% of total forested acreage; maple-beech-birch at 23%; and aspenbirch at 18% (Figure 3). Conifer types, mainly pine and spruce-fir, represent about 18% of theforested area. Wisconsin forests are for the most part mature with the greatest proportion ofstands in the 61-80 year class. About two-thirds of Wisconsin’s forest lands are privately owned.The remaining third is split between federal, state, local government and tribal ownership.Acres of timberland by forest type ite-red-jack cked & other minor01,0002,0003,0004,0005,0006,000Thousand acresFigure 3. Wisconsin timberland area by forest type (FIA data, US Forest Service).Outreach and EducationOutreach and education are tools frequently used by the forest health program to engage thepublic in prevention and management efforts with topical social media posts, blog articles andnews releases. The forest health team made greater use of social media in 2019 than in yearsprior, allowing for rapid communication of forest health concerns to a diverse audience. Duringthe reporting period, eight Facebook posts generated a total of 35,300 direct interactions (likes,comments, clicks, etc.) and appeared in the newsfeeds of over 350,000 Facebook users. Theteam also published 46 blog articles in the reporting period and increased their blog subscriberbase by nearly 1,000 readers. The team attributes this increase to actively recruiting newreaders through distributing sign-up sheets at presentations, advertising in a statewidepublication for landowners and by prominently displaying the sign-up information on the DNRForest Health website. News releases were met with more mixed success with wide variation5

between articles in how many media sites republished them. The communications specialist isexploring ways to better reach the public with this approach. A total of six news releasesgenerated 12 articles from the media, and the links posted to DNR’s Twitter feed engagedalmost 180 individuals.Exotic Species IssuesBeech bark diseaseBeech bark disease is a fatal disease of American beech(Fagus grandifolia). It is a disease complex of a scaleinsect (beech scale, Cryptococcus fagisuga) that causeswounds that are subsequently infected by either of twofungi in the genus Neonectria (N. faginata and N.ditissima). Both the scale and N. faginata are Europeanin origin but N. ditissima is native to North America. In2009, heavy infestations of beech scales and mortality ofbeech were detected for the first time in Wisconsin inDoor County. In surveys done in 2012-13, beech scalewas found to have spread through most of the Wisconsin Figure 4. Counties with beech scaledetections are shown in blue.range of American beech. The first confirmation of aMortality from beech bark disease isNeonectria spp. on a beech tree in association withlimited to Door County in orange.beech scale infestation and beech mortality in Wisconsinwas in 2017 in Door County. Door County remains the only Wisconsin county where bothcomponents of beech bark disease have been found and where mortality from the disease hasoccurred in Wisconsin (Figure. 4).In 2019, site visits within the range of beech in eastern Wisconsin indicated that populations ofbeech scale remained very low in counties other than Door County. Subjectively, scalepopulations in Door county appeared to be declining in areas where they were formerlyabundant. Aerial surveys done in late July recorded no premature yellowing of beech indicativeof beech bark disease stressed and dying trees as seen in past years.Jumping worms (Amynthas spp.)“Jumping worms” is a term used for a group of similar Asiatic worms with an annual lifecycle.Invasive earthworms in the genus Amynthas were first identified in Dane county in 2013 andhave since been reported in 45 of the state’s 72 counties (Figure 5). Verified species inWisconsin are Amynthas tokioensis, A. agrestis, and the closely related, though larger,Metaphire hilgandorfi, first identified in September 2017. A. tokioensis is the most common ofthe three species. A. agrestis typically appears in combination with A. tokioensis but rarely on itsown. Jumping worms have been found primarily in urban or residential areas. This may reflecttheir long distance spread by people moving plants, mulch and soil for use around their homes.6

Or it may be due to reporting bias; there is noformal survey for jumping worms in Wisconsin.All specimens are submitted by the public andare typically collected near where the submitterlives.In the summer of 2018, researchers with theUniversity of Wisconsin Arboretum began atwo-year project on potential control options forjumping worms, funded by the DNR ForestHealth Program. Treatments tested were EarlyBird fertilizer, biochar and diatomaceous earth.Early Bird is an organic, low nitrogen fertilizerused on golf course greens that acts as avermicide. Preliminary data compiled by BradHerrick and Marie Johnston indicate moderateFigure 5. Tinted counties represent the distributionmortality rates in adult jumping worms with theof jumping worms in Wisconsin 2019.use of Early Bird fertilizer but no measurableeffect from biochar or diatomaceous earth.Unfortunately, in 2019, the maker of EarlyBird fertilizer stopped production. Theresearchers substituted Tea tree meal, theprimary ingredient and suspectedvermicidal component of Early Bird. Teatree meal is high in saponins and thesemay be the cause of the injury seen inworms treated with Early Bird fertilizer.This project will continue through July2020.Emerald ash borer (EAB, Agrilusplanipennis)Distribution of EAB in WisconsinIn 2019, EAB was confirmed for the firsttime in Pierce County on the westernborder of the state (Figure 7). The was nochange in quarantine status as the entirestate was placed under quarantine inspring of 2018. State agencies continue torecord subsequent finds at the municipallevel and these indicate that the pestcontinues to spread within known infestedFigure 6. EAB has been confirmed in municipalities indicatedin green or dark blue for tribal land. Gray indicates a tribaljurisdiction where EAB has not been confirmed.7