Emerald Ash Borer


The emerald ash borer is a half-inch long metallic green beetle with the scientific name Agrilus planipennis Fairmaire. Larvae of this beetle feed under the bark of ash trees. Their feeding eventually girdles and kills branches and entire trees. Emerald ash borer was first identified in North America in southeastern Michigan in 2002. In the years since that discovery, the beetle has spread into Minnesota, Wisconsin, Indiana, Illinois, Iowa, Kansas, Missouri, Kentucky, Tennessee, Ohio, Maryland, Virginia, West Virginia, Pennsylvania, New York, Massachusetts, Connecticut, New Hampshire, North Carolina, Ontario and Quebec.

Emerald ash borer feeds exclusively on ash trees in North America. Host species include green ash, white ash, black ash, blue ash, and pumpkin ash. Tens of millions of ash trees have been lost to this pest, which usually kills ash trees within 3-4 years of infestation.

To report possible infested trees in Pennsylvania, contact: The Pennsylvania Department of Agriculture 1-866-253-7189

Symptoms of emerald ash borer infestation include upper crown dieback (Fig. 1), epicormic branching (Fig. 2), bark splits (Fig.3) and bark flaking (Fig.4), or tissue damage (Fig. 5) resulting from woodpecker predation.

Fig. 1 Crown diebackFig. 2 epicormic branchingFig. 3 Bark splittingFig. 4 Bark flakingFig. 5 Woodpecker damage

Signs of emerald ash borer include the adult beetle (Fig. 6) or larva (Fig. 7), “D” shaped exit holes (Fig. 8), and “S” shaped larval galleries under the bark (Fig. 9).

Fig. 6 EAB adultFig. 7 EAB larvaFig. 8 "D" shaped exit holeFig. 9 "S" shaped galleries under bark