Emerald Ash Borer
About Emerald Ash Borer
Emerald ash borer (EAB) is a small, metallic green beetle that kills ash trees. The emerald ash borer is native to Asia and came to the United States around 2002. It moved from eastern United States to the Midwest through firewood, sawmill logs, and nursery plants. The larvae feed on the inner bark of ash trees, preventing delivery of water and nutrients to the tree, causing ash trees to die.
Coralville had a confirmed case of EAB in January 2017. Following patterns in the Midwest, Coralville can expect to lose the majority, if not all, of the ash tree population. Ash trees typically die in two to five years of becoming infected.
The City is taking the following steps to limit the economic, environmental, and aesthetic impacts of EAB:
- Taking inventory of approximately 300 City-owned ash trees in parks and streetscapes in 2016.
- Proactively removing approximately 100 declining or structurally poor ash trees over a five year period beginning in 2016, and processing the wood in accordance with Federal guidelines.
- Planting new trees of an alternate species after removals have taken place, with a goal of diversifying Coralville's urban forest. Proactive planting began in 2015.
- Treating approximately 200 eligible ash trees with insecticidal treatment in 2017. Approximately 100 of these will be candidates for retreatment in 2019, and 50 in 2021.
- Monitoring treated trees and removing those that succumb to EAB, followed by planting new trees.
Photo: PA Dept. of Conservation & Nat. Resources-Forestry, Bugwood.org
Information for Homeowners
Property owners are responsible for the trees on their own property, including the right of way. Homeowners may treat ash trees in the right of way at their own expense. The City recommends systemic injection over other treatment methods (drench, spray, or granular methods) due to the lower risk of pesticide exposure. If an ash tree is not treated, it is anticipated that the tree will be in a declining state within two to four years.
Ash Trees in Right of Way
Planting a tree in the right of way (the public space between the street curb and sidewalk) requires a tree planting permit. Right of Way Tree Planting Permit
- The property owner will be notified that the ash tree must be removed at their own cost when it is dead, dying, or diseased.
If a private property owner has an ash tree that was planted in the right of way with a permit:As the ash population dies, it will be necessary to issue notices for tree removal and systematically remove permitted right of way ash trees.
- The City is responsible for removing the tree within the right of way if it is dead, dying, or diseased (State of Iowa Code III – 1759 364.12).
- The homeowner is responsible for removing or treating the ash tree if it is not dead, dying, or diseased.
Ash Trees on Private Property
Removing or treating ash trees on private property, including yards, is the property owner’s responsibility. On private property, when the City identifies a dead, diseased, or dying tree, or if a tree poses a risk to people or property, the property owner is given a notice to remove the tree at their expense. If the request is not completed, the City removes the tree and assesses the property owner on their taxes.
Ash Trees on Private Woodland Area
Removing or treating ash trees on private woodlands is the property owner’s responsibility. On private woodland property, ash trees that are dead, diseased, or dying that are not causing a dangerous situation or in danger of falling on another person’s property will be left standing. The City recommends these trees be dealt with by the property owner as soon as possible.
Dealing with Door-to-Door EAB Treatment Sales
If I am contacted by a pesticide applicator to treat ash trees for Emerald Ash Borer (EAB), what should I do?
- The best time to make a preventive application for EAB is the spring.
- If you are contacted in the fall or winter, remember that treatment typically happens in the spring. Only some products can be used in the summer and early fall if there is good soil moisture, trees are not heat stressed, and only before leaves start to change color.
- If you live within 15 miles of a confirmed EAB infested site, get multiple estimates for the same type of treatment before any work is done.
- If you live outside the risk zone, thank the applicator for showing interest and keep the company information on file.
- Be wary of aggressive sales techniques or threats that your tree will die if it is not treated immediately.
Commercial Applicators Must Follow State Law
Who can treat my ash tree for EAB?
Ash trees can be protected with insecticide applied by a commercial pesticide applicator or the homeowner. Trees must be healthy, vigorously growing, and valuable to your landscape. Treatment must continue every year or every other year, depending on the pesticide, for the life of the tree.
For an applicator to treat your ash tree for EAB, they must be certified with the Iowa Department of Agriculture and Land Stewardship - Pesticide Bureau. To treat trees commercially, they must have a valid/active category 3O or 3OT certification. Otherwise they are making the treatment against state law.
Verify that Who You Hire Is Certified
How do I know my treatment company is certified?
To get a list of companies registered in your city to do EAB treatment:
- Go to www.iowaagriculture.gov/pesticides.asp
- Under "Pesticide Databases” choose “Licensed Commercial Pesticide Applicator Company”
- Choose “Search by Business City/State/Zip"
- Enter ‘Coralville’ in the city field, and click the drop down menu to select ‘Commercial Applicator’
- Click “Search for one of these criteria”
- Click on each listing to see if a current/active applicator has category 3O or 3OT certifications.
Resources & Information
- Emerald Ash Borer: Coralville Response Plan (adopted April 11, 2017)
- Frequently asked questions about Emerald Ash Borer
- Identifying Emerald Ash Borer
- Interactive tree identification
- Potential Side Effects of EAB Insecticides
- Selecting Trees for Your Yard
- Who can treat my ash tree?
- EAB: To Treat or Not to Treat?