Tree removal and planting
Emerald ash borer (EAB) kills most, if not all, untreated ash trees that it attacks. Trees die 1-4 years after they are first attacked and these dead trees can become fragile relatively quickly, creating a public safety risk. There is a rapid exponential increase in tree death in the few years after EAB is first detected, potentially straining resources. Developing a management plan will help to plan removals to protect people and structures, and manage budgets.
Ash trees are abundant in many communities because they were planted to replace dutch elm disease-killed elm trees. To buffer from possible impacts of future invasive insects or pathogens, plant a diversity of non-ash tree species. Aim to meet or exceed the 30-20-10 guideline - no more than 30% trees from one family, no more than 20% of one genus, and no more than 10% of one species. Underplanting trees in areas with a large component of ash prior to EAB attack may be warranted to help mitigate the impact of tree loses in these areas.
Do not plant ash. It is possible that ash can be planted again in the future. Research on EAB-resistant hybrid ash species is being conducted and this may eventually provide an option. Emerald ash borer populations are expected to crash when most ash are killed, and the future population dynamics of EAB in a landscape with few ash trees is unknown.