First Detector Training EMERALD ASH BORER MONITORING & MANAGEMENT

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1 First Detector Training EMERALD ASH BORER MONITORING & MANAGEMENT

2 EAB Module 3

3 Module Objectives The purpose of this module is to introduce basic knowledge needed to identify an exotic, invasive tree pest called emerald ash borer (EAB). Upon completing this module, you should be able to: Identify EAB larvae and adults Identify native ash species that are hosts of EAB Recognize signs of EAB infestation Recognize symptoms of EAB infestation Kent Loeffler, Cornell University

4 Adult EAB Adults are metallic green in color with bronze undertones EAB adults are about 1/2 long and 1/6 wide, approximately the size of a tic-tac candy EAB adults feed on ash leaves from late May to mid August. After EAB adults emerge from the tree from late May to mid August they mate and then the female will feed on ash leaves for one to two weeks to mature her ovaries prior to egg laying. Kent Loeffler, Cornell University

5 Larval EAB Larvae are flat headed and have body segments resembling nested bells Larvae can be found by stripping the bark from infested branches and trunks Larvae create S-shaped galleries as they feed on the cambium that fill with frass (sawdust-like excrement) Mark Whitmore, Cornell University

6 Larval EAB Larvae feed during warm months and then overwinter as prepupae under ash tree bark or just under the surface of the wood. EAB overwinters as a prepupa in the outer layers of the wood or in the outer bark when it is thick. The prepupa changes into a pupa in late spring, then into an adult which emerges in late May when temperatures get warm. Adult emergence has been found to start at around 400 Growing Degree Days (GDD) base 50 or about when black locust is in flower. Mark Whitmore, Cornell University

7 Life Cycle June/July Oviposition Summer/Fall Larval growth May/June Adult Emergence Ovary maturation Winter Pre-pupae Early spring Pupation EAB eggs, Debbie Miller, USDA FS, Bugwood.org; larva, prepupa and pupa, David Cappaert, Michigan State University, Bugwood.org; EAB exit holes, Daniel Herms, the Ohio State University, Bugwood.org; EAB adult, David Cappaert, Michigan State University, Bugwood.org

8 Larval look-alikes EAB larva on left (Coleoptera: Buprestidae), a flat-headed borer; the native red-headed ash borer, Neoclytus acuminatus on right (Coleoptera: Cerambycidae), a round-headed borer. EAB left: Neoclytus right Photos Mark Whitmore, Cornell University; Neoclytus adult: Gyorgy Csoka, Hungary Forest Research Institute, Bugwood.org Neoclytus adult

9 EAB Look-Alikes Several borers native to North America are closely related to EAB. Two that are also pests of native trees are: 1. Bronze birch borer (Agrilus anxius) 2. Two-lined chestnut borer (Agrilus bilineatus) 1 2 They are similar in size and shape to EAB, but are colored differently and attack different tree hosts. Kent Loeffler, Cornell University

10 EAB Look-Alikes Other insects that resemble EAB include: Clockwise from top left: (1) EAB (2) Trogossitid beetle (3) Dogbane beetle (4) Common green bottle fly (5) Sharpshooter (6) Sweat bee (7) Japanese beetle (8) Six spotted tiger beetle (9) Green stink bug (10) Green June beetle Kent Loeffler, Cornell University For more information about EAB look-alikes, or to download a lookalikes poster visit:

11 EAB Review What color and size are adult EAB? Answer Where do EAB larvae pupate? Answer Name some insects that can be mistaken as EAB? Answer

12 EAB Summary EAB adults and larvae have distinguishing characters that make them easy to identify Adults are metallic green and about ½ long. They are active from May to August Larvae can be found beneath the bark in late summer through late winter, have bell-shaped body segments, and have a tiny, flattened head Kent Loeffler, Cornell University PDCNR - Forestry Archive, Bugwood.org

13 Vulnerable Plant Species The only trees attacked and killed by EAB in North America are ash trees, the genus Fraxinus. There are 16 species of ash in North America and only three are commonly found in New York. White ash (F. americana) and green ash (F. pennsylvanica) are common forest trees and are also frequently planted in urban areas. Black ash (F. nigra) is an important wetland species and is culturally important for Native Americans that use the wood for traditional basketry. Richard Webb, Bugwood.org

14 Ash Trees David Cappaert, Michigan State University, Bugwood.org

15 Ash Trees are easy to Identify All three ash, white, green and black, have: Opposite branching Pinnately compound leaves (5-11 leaflets) Large, stout, terminal buds Noticeable bud scars Oar shaped, dry fruit (samaras) Diamond pattern in the bark (white and green ash) Robert Vidéki, Doronicum Kft., Bugwood.org

16 Opposite branching Buds (therefore leaves and branches) grow directly across from each other. Only a few trees in NY have opposite branching: ash, maple and horsechestnut/buckeye. Opposite, ash Alternate, beech Paul Wray, Iowa State University, Bugwood.org Bill Cook, Michigan State University, Bugwood.org

17 David Cappaert, Michigan State University, Bugwood.org Opposite branching Also, note the stout twigs to hold their large compound leaves

18 Pinnately Compound Leaves Compound leaves: leaves made up of multiple leaflets Pinnate: leaflets arranged linearly along a rachis (stem) Leaflet Rachis Terminal Leaflet 1 Bud Keith Kanoti, Maine Forest Service, Bugwood.org

19 Green ash: 7-9 leaflets Keith Kanoti, Maine Forest Service, Bugwood.org Black ash: 7-11 leaflets White ash: 5-9 (7) leaflets Paul Wray, Iowa State University, Bugwood.org Keith Kanoti, Maine Forest Service, Bugwood.org

20 Large, stout buds. Prominent leaf scars Green Ash Black Ash White Ash Paul Wray, Iowa State University, Bugwood.org Bill Cook, Michigan State University, Bugwood.org Paul Wray, Iowa State University, Bugwood.org

21 Look-alike twigs and buds Norway maple (one of the look-alikes) opposite branches, rounded buds, red stems. Norway Maple Yellow Birch Black Cherry Bill Cook, Michigan State University, Bugwood.org Paul Wray, Iowa State University, Bugwood.org

22 Ash Fruit Ash fruit a single samara: seed surrounded by dry, oar shaped wings that help with dispersal. Green Ash Paul Wray, Iowa State University, Bugwood.org Seed White Ash Franklin Bonner, USFS (ret.), Bugwood.org

23 Ash Bark As white and green ash trees age their bark develops distinct diamond patterns. Young ash trees have smooth bark. Keith Kanoti, Maine Forest Service, Bugwood.org

24 Black Ash Bark Black ash trees have flakey bark as they age but, a diamond pattern may still be seen. Keith Kanoti, Maine Forest Service, Bugwood.org

25 White Ash Bark Thick bark Medium bark Thin bark Mark Whitmore, Cornell University

26 Look-Alike Trees Although ash are quite unique looking, there are a few trees that could be mistaken for ash. Norway maple Box elder Elderberry Mountain-ash (not a true ash) Hickory and walnut

27 Norway Maple Similarities Opposite Branches Diamond Pattern Bark Differences Large, simple leaves Paired samaras Steve Hurst, USDA NRCS PLANTS Database, Bugwood.org Paul Wray, Iowa State University,

28 Box Elder Similarities Opposite branching Compound, pinnate leaves Diamond pattern bark Differences Lobed terminal leaflet 3-5 leaflets Reddish stems/young bark Bill Cook, Michigan State University, Bugwood.org

29 Elderberry Similarities Opposite branching Pinnately compound leaf Differences Shrub Soft/pithy twigs Berries Chris Evans, River to River CWMA, Bugwood.org John Cardina, the Ohio State University, Bugwood.org

30 Mountain Ash Similarities Pinnately compound leaf Differences Leaflet number and serrations Smooth bark Alternate branches Berry like fruit Tom DeGomez, University of Arizona, Bugwood.org Boris Hrasovec, Faculty of Forestry, Bugwood.org

31 Hickories and Walnuts This group of trees primarily has pinnately compound leaves, but alternate branching, nuts and varying bark types (some of which can look diamond like). Bitternut Hickory Shagbark Hickory Black Walnut Paul Wray, Iowa State University, Bugwood.org

32 Summary of Steps to Identify Ash 1. Opposite branching (with stout twigs) 2. Pinnate compound leaves (7) leaflets 4. Single samara 5. Pronounced diamond pattern bark Tom DeGomez, University of Arizona, Bugwood.org Keith Kanoti, Maine Forest Service, Bugwood.org

33 On-line Resources for Ash Know Your Trees: CU Woody Plant Database: Virginia Tech Dendrology:

34 Review What are the two most commonly planted species of ash? Answer What type of leaves and leaf arrangement do ash trees have? Answer What type of fruit do ash trees produce? Answer What is a distinct characteristic of a mature ash tree? Answer

35 Signs & Symptoms of EAB Infestation Symptoms are host responses to pest infestation. Signs are physical clues of a pest that are unrelated to host responses to the pest. Depending on Pest Pressure (PP) it can take 2 or more years for an infested tree to show noticeable signs or symptoms of EAB attack. PP is basically the number of EAB in an area attacking the trees. At the beginning of an infestation when PP is low the trees take years to display Signs & Symptoms. When PP is high tree death can be in 1 to 2 years and the onset of Signs and Symptoms is rapid. Mark Whitmore, Cornell University

36 Signs & Symptoms of EAB Ash with Signs & Symptoms will not be found singly, neighboring trees will also be affected. EAB spread across the landscape infesting trees they will not focus on only one tree. Look around when you find a suspicious tree. Signs & symptoms important in detection are: Woodpecker Foraging Vertical Bark Cracks Canopy Decline Epicormic Sprouts D-shaped Exit Holes S-shaped larval galleries Adult feeding on leaves Mark Whitmore, Cornell University

37 Signs & Symptoms of EAB Infestation Woodpecker foraging: It doesn t take long for woodpeckers to learn that EAB can be found under the bark of ash trees. Usually before any canopy symptoms are present you can find signs that woodpeckers have been feeding on EAB. At first there are just a few places where you can find the bright brown bark exposed and a spot where the woodpecker has reached in the bark to pull out an EAB. These are usually dispersed around the trunk in a checkerboard-like pattern. As EAB populations increase the bark will be more thoroughly removed from larger areas and can be easily seen from a distance, especially when the bark is wet. Mark Whitmore, Cornell University

38 Key to Recognizing Woodpecker Foraging on EAB Fresh bark flaking easiest to see when wet Look for the light brown color of freshly flaked bark. Look for holes where the woodpecker has found a prey. How deep is the foraging Are they foraging deep in the wood or remaining in the bark? Are they foraging in sound wood or punky, rotten wood? Pattern of foraging Dispersed in checkerboard manner Large swaths of freshly flaked bark All in a line and old = not EAB Mark Whitmore, Cornell University

39 Signs & Symptoms of EAB Infestation Bark Cracking: This is the earliest sign of EAB infestation. This occurs when the first EAB attacks are few and far between on the stem of an ash. The bark is killed above the spot where the EAB have fed, but the surrounding inner bark is perfectly healthy and the tree continues to grow. With low PP it can take years for EAB populations to build to the point where they are killing trees. Every year the tree grows after the initial attacks the areas of dead bark will split wider and wider and the EAB gallery beneath can be seen. Mark Whitmore, Cornell University

40 Signs & Symptoms of EAB Infestation S shaped galleries and D shaped exit holes: When you see woodpecker foraging on a tree and perhaps some bark cracks then chances are closer examination will reveal the D shaped holes adult EAB make as they chew their way out through the bark. These can be small, usually only 3 to 4 mm wide. When you peel away the bark of an ash infested with EAB their typical S shaped galleries. Even when EAB densities are very high and most of the galleries are obscured closer examination will reveal signs of this typical gallery shape. Mark Whitmore, Cornell University

41 Signs & Symptoms of EAB Infestation Canopy thinning: Canopy thinning can take years to become apparent at the beginning of an infestation when the PP is low. Canopy thinning is caused not so much by branches dying, but by the general leaflet size decreasing because EAB has cut off the flow of nutrients for full leaf-out. Usually by the time canopy thinning is noticed the trees have suffered considerable loss of inner bark and will be unable to recover using pesticide treatments. Mark Whitmore, Cornell University

42 Signs & Symptoms of EAB Infestation Epicormic sprouting, or water sprouting, is a response by the tree to fill out canopy that has been lost by some physical means such as EAB killing the upper parts of a tree. Green ash are strong sprouters, whereas white ash produce fewer and less vigorous sprouts. By the time epicormic sprouting appears the trees have suffered considerable loss of inner bark and will be unable to recover using pesticide treatments. Jodie Ellis, Purdue University

43 Review What are two symptoms of EAB infestation in ash trees? Answer What symptoms would you look for on the trunk of the ash tree? Answer

44 Module Summary Emerald Ash Borer: Adults are metallic green and about ½ long. They are active from May-August. Larvae are found beneath the bark, have bell shaped segments and a tiny, flattened head. Ash Trees: Opposite branching with pinnately compound leaves A distinct diamond-shaped pattern in mature bark Oar-shaped seeds (samaras) that hang in clusters Infestation Signs and Symptoms: Splitting of the bark Woodpecker foraging on trunk S-shaped feeding galleries beneath the bark D-shaped exit holes Canopy thinning and branch dieback in tree canopy Epicormic shoots at base of tree

45 Credits Content adapted from the NPDN EAB modules prepared at Virginia Tech; published June 2010 Mark Whitmore, Forest Entomologist with Cornell University Department of Natural Resources, Prepared by Rachel McCarthy, NEPDN Education and Training Coordinator, Department of Plant Pathology and Plant-Microbe Biology, Cornell University,