Several species of ash trees are native to the United States. Almost a quarter of street trees in Madison are ashes, because the city planted so many after Dutch Elm Disease decimated our urban forest. Now, the city plans to pre-emptively destroy many of the ash trees because they might become infected by emerald ash borer.
Emerald ash borer (EAB) is an invasive insect that lays its eggs in ash trees. In its native range EAB does not harm ash trees, but in the United States ashes are sometimes killed by the actions of the insect’s larvae.
EAB is naturally very slow-moving, but its dispersal has been sped up by the transport of infected firewood. It was first found in Madison in November 2013. It lives in all species of true ash trees, but not in mountain ashes.
Like all trees, ashes provide many benefits to people. There are many effective treatments against EAB, including trap, decoy, barrier, and chemical techniques, that seek to eliminate harmful invasive insects, rather than beneficial native trees. A Facebook group has been created to protest Madison’s decision to destroy healthy trees rather than protecting them against the chance of infection.
Ash trees in yards can be given an opportunity to fight off infection on their own, or may be helped out through one or more treatment methods. They are not doomed to die and become hazards, as some sources would have you believe.