Emerald Ash Borer Information

The presence of the Emerald Ash Borer has been confirmed in Sioux Center. Over time, this insect will infest local ash trees and cause them to decline and die. 

Information for tree owners:

Step 1: Identify your tree

Ash trees have branches that grow directly across from each other and compound leaves (a group of leaflets joined by a stalk to a woody stem). 

Use an interactive tree identification key through Iowa State University Extension. 

Step 2: Evaluate tree health

Signs and Symptoms of Emerald Ash Borer presence:

  • Canopy dieback - Begins in top 1/3 of tree's canopy.
  • Bark splitting - Vertical cracks in bark, revealing "feeding galleries" - serpentine paths eaten into the tree.
  • Serpentine "feeding galleries"  - visible paths where the larva ate tree tissue and D-shaped exit holes where adult Emerald Ash Borers emerge.
  • Increased woodpecker activity/damage - Missing bark where birds foraged and holes where they pulled out insects.
  • Adult Emerald Ash Borers or larva visible - Adults are bright metallic green, 1/2-inch long. Larva are creamy white, legless, with segmented bodies.

More information on Signs and Symptoms of Emerald Ash Borer

Contact a local nursery or tree service provider to determine health of ash tree. This may involve a service charge to visit the tree. 

Step 3: Decide when and how to take action

• Treat the ash tree – Hire a certified specialist to determine effectiveness and apply pesticides. Beware of scams. Several local nurseries are certified to treat trees for Emerald Ash Borer. Treatment must be done annually or every-other-year, depending on the type of insecticide.

• Remove a failing ash tree –  If the tree is failing, hire a tree service to cut down a tree. Ash trees should not be removed June 1-Sept. 1, as EABs are in the adult stage in the summer and tree removal may increase their spread/range.

• Take no action yet – All ash trees will likely be impacted by EAB and decline and die, but that may take place over a number of years. Contact a local nursery or tree service provider to determine tree’s health.


Once the Emerald Ash Borer is identified in a community, scam artists may try to take advantage of the situation.

  • Only hire a certified specialist to apply pesticides.
  • If companies offer cures or preventive treatments, thank them for their interest and ask them to leave your property. 
  • If someone claims the state has ordered your ash trees to be removed and offers to cut them down for a price, record the person’s name and contact information and report it to the IDALS – State Entomologist Office at (515) 725-1465.

Additional resources

Learn more about the Emerald Ash Borer: