Many of our clients have been asking about this question in recent weeks. Thus far, Emerald Ash Borer (EAB) infestations have been confirmed in 9 counties in Nebraska. They appear to be on the slow gradual trajectory that has been observed in states such as Michigan, Illinois and Ohio, and is expected to become more and more common in the next 3-4 years.
The latest on EAB is depicted in the map referenced below:
Nebraska Extension in Douglas-Sarpy Counties advises property owners to be aware of its presence in eastern and central Nebraska and make a “keep or remove” decision on each of their ash trees. This is a complicated decision, involving several factors. The considerations that we advise clients to think through are:
Age of tree – If a tree is a very young tree, the owner doesn’t have too many years invested in it and it’s probably best to remove it and replace it with a different species that will serve the same purpose. If it’s a tree that is older than 70 or so years, it becomes difficult to treat and get enough insecticide in the tree to protect it against the beetles and may be a good target for removal. A tree that is less than 15 inches in diameter can be treated by the property owner each year in mid-May; it’s important to read and follow all label directions. We recommend that trees of greater diameter should be treated by a Nebraska Arborists Association (NAA) or International Society of Arboriculture (ISA) Certified Arborist. Property owners can find certified arborists at:
Location on the property – If a tree is placed well on the property, then keeping and treating it may be wise. For example, if it’s on the southwest side of the house or the patio, it’s providing tremendous shading/cooling benefit. If, on the other hand, it’s in the far reaches of the property, there isn’t much benefit to the property owner. Additionally, ash trees growing under power lines or between the street and sidewalk are in poor locations and should be considered for removal.
Overall condition of tree other than EAB – If the tree is healthy other than the looming EAB issue, having no trunk or branch cracks, basal decay, co-dominant leaders, is not leaning, etc. then it’s a better candidate for remaining in the landscape than if any of these defects are limiting tree growth. Compaction of the soil and previously cut roots are also important considerations.
If the property owner is seeking additional guidance on making an EAB decision, we recommend that they reach out to a certified arborist for a consultation. They can also contact our office at (402) 44-7804.