West Des Moines, IA

Emerald Ash Borer (EAB) FAQ's

• What is the emerald ash borer (EAB)?

  The emerald ash borer (EAB) is an invasive insect that has killed tens of millions of ash trees in North America since it was first discovered in 2002.  It attacks all ash tree species and is considered one of the most destructive tree pests in North America.

• How does EAB damage ash trees?

  EAB larvae feed on live tree tissue, which prevents the tree from transporting water and nutrients.  Signs that a tree may be infested include:

  • Thinning or dying branches at the top of the tree
  • Excessive woodpecker activity
  • Numerous sprouts growing from any part of the tree
  • Presence of EAB larvae or adult insects

• Why are dead or dying ash trees dangerous?

  Dead and dying ash trees are brittle and unstable, which makes them a serious safety hazard.

  • Branches can fall unexpectedly, even in calm weather
  • Falling branches can damage property, vehicles or people
  • Trees that pose a risk to neighboring property may be considered a nuisance, and the City can require their removal

  Property owners with untreated ash trees should have them assessed by a licensed professional and either treated or removed.

• What has the City of West Des Moines done about EAB?

  The City implemented its EAB Management Plan before EAB was confirmed in Polk County, treating the area as if the insect was already present.

  • The Parks & Recreation Department assessed all public ash trees - over 1,100 trees in parks, rights-of-way, medians, and around city buildings
  • The Urban Forestry Supervisor used this information to schedule pre-emptive removals of high-risk trees
  • Preventative treatment of over 800 public ash trees began in May 2015
  • Most removed trees were replaced with a diverse species from the Iowa DNR Ash Replacement List

• What should residents do if they have ash trees on private property?

  Residents should monitor their ash trees for signs of EAB.  If trees are untreated and at risk, they should be assessed by a licensed professional and either treated or removed to prevent hazards and protect neighboring properties.