Since the 1960s ash trees were often planted in home landscapes, parks and public areas because they were in good supply in nurseries and grow quickly compared with other tree species. However, ash trees are not currently being stocked and sold much along the Front Range of Colorado due to finding Emerald Ash Borer (EAB) in Boulder, CO in the Fall of 2013. Emerald Ash Borer is a very serious pest that kills ash trees. Larvae feed under the bark, eventually girdling the tree and cutting off nutrients. Ash trees are typically killed within 2-4 years of first symptoms, even previously healthy tress. Ash trees of all sizes can be attacked from ½ inch saplings to large mature trees. The insect is very difficult to detect because it is under the bark and adults are only around May to September.
Homeowners with ash trees on their property can go to www.eabcolorado.com for recommendations on potential EABtreatments and ash tree management. This website will help you make an informed decision whether you should try to save your ash tree or eventually replace with a more desirable tree.
Ash trees are also home to many other insects. Most common are ash sawfly, ash borer and oystershell scale.
For more information, see the following Planttalk Colorado™ script(s).
For more information, see the following Colorado State University Extension fact sheet(s).
- Cytospora Canker
- Aphids on Shade Trees and Ornamentals
- Oystershell Scale
- Shade Tree Borers
- Brownheaded Ash Sawfly
- Xeriscaping: Trees and Shrubs
- Trees and Shrubs for Mountain Areas
- The Science of Planting Trees
- Large Deciduous Trees