General Impact
Nomura (2002) states that, "During the early stage of an infestation, when A. planipennis population is low, the initial damage is low. However, after 2 to 3 years of continuous infestation, the population builds up, and eventually the tree's nutrient and water transport system is disrupted, culminating in wilting and eventual tree mortality. A. planipennis will kill apparently healthy trees during high beetle population levels which are probably triggered by a few years of hot and dry climatic conditions. A. planipennis can cause severe damage to ash stands over 8 years of age that are not crown-closed, with good sun light penetration, and that are comprised of trees with bark fractures. After 1 to 2 years of infestation, the bark often falls off in pieces from damaged trees thereby exposing the tunnel-ridden sapwood."
Nomura (2002) reports that damage consists of, "D-shaped exit holes along the lower bole surface are clear signs of buprestid beetle activity, however, careful examination is required as these are very cryptic. Frass filled, zigzagging tunnels about 6mm wide at the sapwood/bast interface are signs of A. planipennis feeding. Callus tissue produced by the tree in response to larval feeding may cause vertical splits 5 -10cm in length to occur in the bark above a gallery." MDNR (2004) states that, "Infested trees exhibit top-down dieback, with 1/3 to 1/2 of branches dying the first year and the remaining canopy dying the following year. This is often followed by a large number of shoots arising below the dead portions of the trunk. Borers make a small (1/16 inch diameter) "D"-shaped hole when entering the tree and several distinct "S"-shaped tunnels may be present under the bark. Trees may also exhibit 5-10cm vertical splits in the bark in response to larval feeding.
A. planipennis attacks ash trees in the genus Fraxinus. All North American ash species that occur within the current EAB range have been killed by EAB, including white ash (F. Americana), green ash (F. pennsylvanica), black ash (F. nigra), blue ash (F. quadrangulara) and pumpkin ash (F. profunda) (Lindell et al. 2008). Attacks on non-ash species have not been observed in North America to date, but there is concern that other species could be vulnerable. If A. planipennis host range extends beyond Fraxinus spp., the impacts of this invasive pest in North American forests would increase dramatically. Anulewicz et al. (2008) assessed A. planipennis landing rates, oviposition and larval development in a number of North American tree species. They found that “although A. planipennis adults will occasionally land on and oviposit on logs and trees of non-ash species, A. planipennis larvae did not successfully develop on anything other than Fraxinus species” (Anulewicz et al. 2008).
The three main ash species in Europe are F. excelsior, the most widespread species, and F. ornus and F. angustifolia. Nothing is known of the susceptibility of these to A. planipennis, so evaluating the resistance of these European species should be a research priority. F. excelsior is a common forest and urban tree used for timber, flooring, tool making and for its medicinal properties (FRAXIGEN 2005 in Baranchikov et al. 2008). All three species are important components of forest ecosystems in Europe and “their disappearance would have serious consequences for native biodiversity and ecosystem services” (Baranchikov et al. 2008).
Location Specific Impacts:United States (USA) 
Economic/Livelihoods: USDA has spent more than $100 million on research, eradication and reforestation efforts. USDA estimates that if EAB is not contained or eradicated, it has the potential to cost state and local governments approximately $7 billion over the next 25 years to remove and replace dead and dying ash trees that can pose a safety hazard in urban and suburban areas (APHIS 2006).
Reduction in native biodiversity: The emerald ash borer is responsible for the death and decline of more 25 million ash trees in the United States (APHIS 2006). Michigan (United States (USA))
Economic/Livelihoods: It is estimated that as much as $11.6 million has been lost as a result of damages to landscapes and woodlots. A further $2 million has been estimated as the loss to the nursery industry as a result of the quarantine restricting sales of ash species. The costs for eradication over the next 10-13 years has been estimated to exceed $350 million (Herms et al. 2003) Ohio (United States (USA))
Economic/Livelihoods: The Ohio Department of Natural Resources estimates that there are more than 3.8 billion ash trees in Ohio, with a standing timber value of more than $1 billion. Ash is an important landscape and nursery species. Eradication costs for the localized infestation in Lucas county , in April 2003 was over $300,000 (Herms et al. 2003).
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