Practical information to identify and manage non-native, invasive plants and animals
The Quiet Invasion:
A Guide to Invasive Species of the Galveston Bay Area
Emerald ash borer
Agrilus planipennis

ITIS TSN:188437
Presence:Species of Concern
Habitat:Terrestrial
Native Range:China and East Asia
Human Health
This species poses no known human health impacts.
Prohibited Lists
As of 2010, Texas is not included in the quarantine area for this species. The U.S. Department of Agriculture (USDA) along with some state governments have established quarantine areas to prohibit the movement of ash tree (Fraxinus sp.) materials and hardwood firewood out of states where the emerald ash borer is known to exist (see geographic distribution below) (USDA 2009b).
Introduction Pathways
Human activities that involve the movement of wood products are the primary cause of long distance spread. This includes moving infested trees, logs, and firewood. The other forms of introduction are through the plant nursery trade and the movement of infected plant nursery stock (ISSG 2009d).
Geographic Distribution
As of 2010, this species is not reported in Texas. Reports of infestations exist for Illinois, Indiana, Ohio, Michigan, Kentucky, Maryland, Minnesota, Missouri, New York, Pennsylvania, Virginia, West Virginia, and Wisconsin.
Specific Primary Habitats
Occurs in trees of agricultural areas, forests, and urban areas. Ash trees (Fraxinus sp.) serve as the primary hosts to this species in North America. All ash species (including green, white, black, and blue) are at risk (Anulewicz et al. 2008; USDA 2009b). Emerald ash borer adults will occasionally land on and deposit eggs on logs and trees of non-ash species. However, in North America, larvae do not successfully develop on anything other than ash species (Anulewicz et al. 2008).
Ecological, Economic, or Social Impact
This beetle is responsible for the death or decline of tens of millions ash trees in North American natural and urban areas (USDA 2009b). Emerald ash borer is difficult to detect early because tree decline is gradual. When infested trees are found, it may be one year or more after the infestation began (ISSG 2009d).
Physical Description
The adult emerald ash borer is small (7-14 mm long and 3 mm wide). The body is narrow and wedge-shaped with a metallic green color; the abdomen is an iridescent reddish-purple. Eggs of the emerald ash borer are white when first laid but turn reddish brown within 2-3 days. Mature larvae and pupae are creamy white in color.
Reproduction Characteristics
In temperate regions, this species can develop from egg to adult in as little as one year. Adults emerge from overwintering sites under bark and mate during the summer months (May to August).  Females lay eggs (on average 70-80 eggs) in bark crevices with eggs hatching in approximately 10 days. The eggs develop into worm-like larvae, which tunnel under the bark to feed on tree tissue. Larvae lay dormant during the winter and emerge from trees in May as adults, leaving a unique D-shaped exit hole (USDA 2009b).
Feeding
Emerald ash borer larvae tunnel into and feed on tree tissue (phloem and outer sapwood). It is this tunneling and feeding that eventually kills the tree.
Control
Since early detection is key to preventing the spread and establishment of this species, regional/local monitoring or surveillance is essential. Firewood and other tree materials should not be moved from quarantine areas. Infested trees should be removed (with the wood chipped and burned) and the remaining tree stump should be grinded.

This species belongs to the following lists:
Images
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Closeup of the adult emerald ash borer (<i>A. planipennis</i>). Photo courtesy David Cappaert, Michigan State University, Bugwood.org.
Closeup of the adult emerald ash borer (A. planipennis). Photo courtesy David Cappaert, Michigan State University, Bugwood.org.
Galleries of the emerald ash borer (<i>A. planipennis</i>). Photo courtesy Toby Petrice, USDA Forest Service, Bugwood.org.
Galleries of the emerald ash borer (A. planipennis). Photo courtesy Toby Petrice, USDA Forest Service, Bugwood.org.
Eggs of the emerald ash borer (<i>A. planipennis</i>). Photo courtesy David Cappaert, Michigan State University, Bugwood.org.
Eggs of the emerald ash borer (A. planipennis). Photo courtesy David Cappaert, Michigan State University, Bugwood.org.
Page Updated/Reviewed: 08/31/2010 11:20 AM
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