2016 Forest Health Highlights Minnesota Department of Natural Resources Division of Forestry Forest Health Unit 1 The Minnesota Department of Natural Resources Forest Health Highlights reports was created by the Division of Forestry Forest Health Unit. Cover photos, clockwise from left: jack pine budworm damage, twolined chestnut borer damage, forest tent caterpillars Photo credits: photos and other images are from DNR forest health staff unless indicated otherwise. Projects were funded in whole or in part through a grant awarded by the US forest Service, Northeastern Area state and Private Forestry. Equal opportunity to participate in and benefit from programs of the Minnesota Department of Natural Resources is available to all individuals regardless of race, color, creed, religion, national origin, sex, marital status, public assistance status, age, sexual orientation, disability, or activity on behalf of a local human-rights commission. Discrimination inquiries should be sent to Minnesota DNR, 500 Lafayette Road, St. Paul, MN 55155-4049 or to the Equal Opportunity Office, Department of the Interior, Washington, D.C. 20240 2 Contents Minnesota Department of Natural Resources (DNR) Division of Forestry Forest Health Staff ..... 6 Welcome Mike Parisio and Jess Hartshorn! ................................................................................... 7 Comparison of Aerial Survey Results in 2015 and 2016 ................................................................. 8 Insects ........................................................................................................................................... 10 Bark beetles of pine and spruce ............................................................................................... 10 Eastern larch beetle .................................................................................................................. 11 Emerald ash borer (EAB) ........................................................................................................... 14 Forest tent caterpillar (FTC) ...................................................................................................... 17 Gypsy moth ............................................................................................................................... 20 Jack pine budworm ................................................................................................................... 21 Larch casebearer ....................................................................................................................... 23 Spruce budworm ....................................................................................................................... 25 Twolined chestnut borer ........................................................................................................... 27 Diseases ......................................................................................................................................... 29 Bur oak blight ............................................................................................................................ 29 Oak wilt ..................................................................................................................................... 31 Early Detection Projects for Oak Wilt ................................................................................... 33 Heterobasidion root disease ..................................................................................................... 36 Diplodia ..................................................................................................................................... 38 Pine-oak and pine-pine gall rusts .............................................................................................. 39 Wet conditions lead to widespread spruce needle rust ........................................................... 41 Environmental Stress Agents ........................................................................................................ 42 Aspen and birch decline ............................................................................................................ 42 Black ash decline ....................................................................................................................... 44 Wildfire ..................................................................................................................................... 46 3 Wind .......................................................................................................................................... 47 Hail damage .............................................................................................................................. 49 Flooding ..................................................................................................................................... 52 Drought ..................................................................................................................................... 52 Late frost wreaks havoc on young buds ................................................................................... 54 Phenology of tree pests and tree health events in 2016 .............................................................. 57 Other Accomplishments ............................................................................................................... 58 New specifications in timber appraisal guidelines for state lands ........................................... 58 News articles ............................................................................................................................. 58 New DNR Forest Health Internet Outreach Material ............................................................... 59 4 5 Minnesota Department of Natural Resources (DNR) Division of Forestry Forest Health Staff Andrew Arends, Forest Operations and Management Section Manager 500 Lafayette Road St. Paul, MN 55155 651-259-5261 [email protected] Val Cervenka, Forest Health Program Consultant 500 Lafayette Road St. Paul, MN 55155 651-259-5261 [email protected] Jess Hartshorn, NE Region Forest Health Specialist 1201 East Hwy 2 Grand Rapids, MN 55744-3296 [email protected] 218-328-8897 Mike Parisio, NW Region Forest Health Specialist 2115 Birchmont Beach Road NE Bemidji, MN 56601 218-308-2363 [email protected] Brian Schwingle, Central Region Forest Health Specialist 1200 Warner Road St. Paul, MN 55106 651-259-5821 [email protected] 6 Welcome Mike Parisio and Jess Hartshorn! We are happy to announce that in June 2016 we added two forest entomologists to the forest health staff, replacing the vacated seats held by long-time forest health specialists Mike and Jana Albers. Jess Hartshorn, Northeast Region forest health specialist, grew up in Dayton, Ohio. She developed a passion for forest health during her undergraduate studies at Southern Illinois University. She received her MS and PhD in forest entomology at the University of Arkansas. During graduate school, Jess studied the life history and mortality factors of a native woodwasp in preparation for the invasion of a related non-native species, Sirex noctilio. Mike Parisio, Northwest Region forest health specialist, grew up in the Catskill Mountains of upstate New York. After watching emerald ash borer destroy many favorite forested areas in Catskill State Park, he made the decision to attend the SUNY College of Environmental Science and Forestry to study forest entomology, and more specifically, emerald ash borer biological control. Mike gained additional forest health-related experience while working for the New York State Department of Environmental Conservation, the SUNY Research Foundation, and the NYS Office of Parks, Recreation, and Historical Preservation. Mike and Jess hit the ground running. With experienced guidance from Brian Schwingle, Central Region forest health specialist, both have quickly settled into a field routine that includes responding to requests from DNR foresters, ground-checking aerial survey polygons for accuracy, writing for our newsletters and web pages, and participating in staff insect and disease training. Our team is once again complete, and as always, we look forward to serving our DNR foresters and the greater forestry community of Minnesota. 7 Comparison of Aerial Survey Results in 2015 and 2016 Damage agent Acres Affected in Acres Affected in Comments 2015 2016 Aspen and birch 38,948 15,052 blank decline Bark beetles 3,154 65 Excludes bark beetles of hardwoods and tamarack; the 2016 value is an underestimate but still accurately reflects a declining trend in bark beetle populations. Birch leafminer Not detected 932 A single large outbreak was observed on Ottertail Point in Leach Lake (Cass Co.). Black ash decline 30,483 Not surveyed blank Eastern larch beetle 33,786 71,157 Widespread tamarack damage and mortality continues across the northern regions of Minnesota. Emerald ash borer Not Surveyed 3,891 Only Winona and Houston counties were surveyed, so this is an underestimate for 2016. Fire 7,507 1,557 Some parts of Minnesota that had forest fires in 2016 were not surveyed. Flooding 1,066 5,692 Parts of southern Minnesota that experienced flooding in 2016 were not surveyed. Forest tent 65,750 14,798 The 2016 value is likely an underestimate caterpillar due to impartial coverage of the state. 8 Damage agent Acres Affected in Acres Affected in Comments 2015