What to do if you have ash trees
Arapahoe县 has identified its first case of Emerald Ash Borer, an invasive insect that infests and kills North American species of ash trees. The case was detected in a small area in northeast 利特尔顿 and was confirmed by Arapahoe县 agencies, Colorado State University Extension specialists, and experts from surrounding municipalities.
Emerald Ash Borer was first discovered in Colorado in Boulder County in 2013. 从那时起, the destructive wood-boring beetles have been found in Broomfield, 此外, 伊利和桑顿. 利特尔顿 has not had a confirmed case of EAB until this June. The town of Carbondale also recently reported a confirmed case discovered on June 16.
"EAB is the most destructive insect pest in trees that we have ever seen in North America. 首页owners and HOAs with ash trees will eventually have a significant financial decision to make whether they choose to treat their ash trees with insecticides or remove them,丽莎·梅森说。, Horticulture Specialist and Entomologist at Colorado State University Extension in Arapahoe县.
Emerald Ash Borer beetles target – and eventually kill – North American ash tree species including green and white varieties, and their cultivars such as "autumn purple ash," a popular white ash variety in Colorado. On average, 15% of urban trees are ash trees.
"An unhealthy ash tree doesn't mean it has EAB,” said Mason. “Look for the distinctive D-shaped exit holes, bark splits and S-shaped tunnels called galleries underneath the bark, gradual canopy thinning and dieback, abnormal shoots of growth, smaller than normal leaves, and heavy woodpecker activity."
Residents can take steps to protect healthy ash trees, but certain options such as insecticide treatments depend on the size and health of each tree. Since Emerald Ash Borer kills trees over a period of several years, trees that are not candidates for insecticide treatments will eventually need to be removed. Residents should follow available guidelines for properly disposing of any infested wood.
"EAB has spread slower than expected in Colorado giving people time to make the right decision,梅森说. “One study showed that healthy ash trees can be treated with emamectin benzoate successfully after EAB has infested the tree as long as the tree hasn't lost more than approximately 30% of the canopy."
Arapahoe县 municipalities are currently prioritizing ash tree insecticide treatment and removal. Other services and community programs may be available to residents to help subsidize the costs of treatment or removal and to mitigate the impacts of Emerald Ash Borer on private property.
Residents should contact their local municipality for information and resources:
For questions about Emerald Ash Borer as well as possible diagnosis and treatment options, contact CSU Extension-Arapahoe县 at MasterGardener@zouxigx.net or 303-730-1920.
