Emerald Ash Borer (EAB) was found in Boulder, CO, in September 2013. As a non-native insect, EAB lacks predators to keep it in check. EAB only attacks ash trees in the genus Fraxinus (so mountain ash are not susceptible).
Approximately 15% of the trees that make up Colorado's urban forest are ash. There are an estimated 98,000 in the city of Boulder alone. The Denver Metro area has an estimated 1.45 million ash trees. EAB is responsible for the death of millions of ash trees in the United States.
Help protect Colorado's ash trees! Don't move firewood, and consider chemical treatments to protect high-value ash trees within or near the EAB Quarantine area.
Where has the EAB been found?
The destructive emerald ash borer has made its first incursion into the backcountry of Great Smoky Mountains National Park, where it could do serious damage to hardwood forests, according to National Park Service biologists.
The ash borer is a non-native species that was introduced from Asia and first discovered in southern Michigan in 2002. In just 10 years, the bugs have spread to 16 states and two Canadian provinces killing tens of millions of ash trees.
The emerald ash borer is a half-inch inch-long metallic green beetle that lays eggs on the bark on all species of ash trees. After hatching, the larvae burrow under the bark, and create feeding tunnels that cut off nutrient and water flow to the tree. The tree can die in three to five years.
Since 2009, officials have been monitoring for the presence of the invasive pest. Front country infestations were confirmed in June 2012 at Sugarlands Visitor Center and at the Greenbrier entrance to the Park.
An off-duty park employee discovered the backcountry infestation on an administrative trail in the Greenbrier area in early November. The employee noticed a pile of bark chips at the base of several ash trees. Signs of woodpecker activity on ash trees is an excellent indicator of an EAB infestation.
Paul Merten, a forest insect specialist from the USDA Forest Service in Asheville, NC, confirmed EAB at the site by looking under ash tree bark for feeding tunnels left by the immature beetle.
“The infestation is well established, probably two years old or older,” Merten said.
Complete eradication of EAB is not currently feasible, but Park Resource Managers are developing a management plan to maintain public safety and protect ash trees where possible. EAB and other tree pests can be transported in firewood. Park regulations prohibit bringing firewood to the Smokies from areas that have been quarantined for EAB or other destructive pests.
Emerald Ash Borer
Emerald ash borer (EAB), Agrilus planipennis Fairmaire, is an exotic beetle that was discovered in southeastern Michigan near Detroit in the summer of 2002. The adult beetles nibble on ash foliage but cause little damage. The larvae (the immature stage) feed on the inner bark of ash trees, disrupting the tree's ability to transport water and nutrients. Emerald ash borer probably arrived in the United States on solid wood packing material carried in cargo ships or airplanes originating in its native Asia. Emerald ash borer is also established in Windsor, Ontario, was found in Ohio in 2003, northern Indiana in 2004, northern Illinois and Maryland in 2006, western Pennsylvania and West Virginia in 2007, Wisconsin, Missouri and Virginia in the summer of 2008, Minnesota, New York, Kentucky in the spring of 2009, Iowa in the spring of 2010, Tennessee in the summer of 2010, Connecticut, Kansas, and Massachusetts in the summer of 2012, New Hampshire in the spring of 2013, North Carolina and Georgia in the summer of 2013, Colorado in the fall of 2013, New Jersey in the spring of 2014, Arkansas in the summer of 2014, and Louisiana in the winter of 2015. Since its discovery, EAB has:
Killed hundreds of millions of ash trees in North America.
Caused regulatory agencies and the USDA to enforce quarantines (Michigan, Connecticut, Georgia, Illinois, Indiana, Iowa, Kansas, Kentucky, Maryland, Massachusetts, Minnesota, Missouri, Ohio, New Hampshire, New York, North Carolina, Ontario, Pennsylvania, Tennessee, Virginia, West Virginia, Wisconsin, and Quebec) and fines to prevent potentially infested ash trees, logs or hardwood firewood from moving out of areas where EAB occurs.
Cost municipalities, property owners, nursery operators and forest products industries hundreds of millions of dollars.
EAB was originally detected in Colorado in the fall of 2013. Delimitation surveys initiated in 2013 followed a scientific protocol developed by the Canadian Forest Service. Subsequent surveys initiated in 2014, 2015 and 2016 have targeted ash trees exhibiting symptoms of decline.
Many ash trees all over the state of Colorado are in poor condition due to freeze, drought and other environmental conditions. Ash pests such as lilac ash borer, ash bark beetle and other boring insects are much more common than EAB.
Update on EAB in Boulder County - Watch Your Ash
Watch Your Ash is a multimedia project created by graduate students at the University of Colorado providing an excellent overview of EAB detection and management in Boulder.
Summit County, Colorado