Is your ash tree worth protecting? University of Illinois Extension says ash trees with 70% or more of their canopy left can likely recover with insecticide treatment, and treatments last one to three years depending on the product. With the leaves down, it is easier to see how much of the crown is still healthy before spring. Buds Tree Care Inc, an ISA Certified Arborist serving Champaign, IL, offers tree health evaluations to help you decide between treatment and removal. Questions are welcome, or request a visit at budstreecare.com. Source: University of Illinois Extension, https://extension.illinois.edu/insects/emerald-ash-borer
Extension: ash trees with 70% or more of their canopy left can likely recover with insecticide treatment.