When it comes to the Emerald Ash Borer, inspect and treat your trees early— or lose them.

If you live in an area where mature trees are abundant you are going to find some variety of Fraxinus, more commonly known as the Ash tree. Ash trees are popular trees in landscapes, parks, and lining city streets because they are easy to care for and provide ample shade.

For the past two decades, though, this species has been under attack by a wood-boring beetle known as the Emerald Ash Borer (EAB).

“Unfortunately, the EAB is a huge threat to Missouri’s trees and time is running out to treat them before there’s nothing we can do to save them,” said Craig Small, certified arborist and owner of Craig’s Tree Service. The University of Missouri Extension Center notes that, “Once EAB has infested an area, standing dead trees will be a serious threat to public safety and the cost of removing dead trees will be very high for homeowners and communities alike.”

A Little History on the Emerald Ash Borer

The Emerald Ash Borer arrived in the United States hidden in wooden packing crates shipped from Asia. In 2002, the EAB was found in southeastern Michigan, where millions of Detroit’s trees were infested. Since this time, the beetle radiated to the Midwest and began its path of destruction.

Scientists and arborists have been working to detect, manage, and eradicate the non-native beetle with traps, by breeding resistant trees, and through other methods.

Adult beetles can move from tree to tree, but the main cause of the widespread infestation in unaffected regions has been transporting logs, firewood, and nursery stock. These materials can spread the infestation even if no beetles are visible. Once a tree is infested, it typically loses its canopy within two years and dies within four years.

The Emerald Ash Borer will attack all 16 species of Ash trees and can destroy all of them, whether they’re in parks, cities, or forests. According to the United States Department of Agriculture, the EAB is credited with the destruction of tens of millions of Ash trees in more than 30 states, including Missouri.

“Since its discovery, EAB has killed tens of millions of ash trees and has cost municipalities, property owners, nursery operators, and forest products industries tens of millions of dollars,” the USDA website states.

Signs Your Ash Trees May Be In Trouble

If you have Ash trees on your property, it’s recommended that you get them inspected for these invasive and destructive insects before they become a problem. Here are a few signs your tree may be infected:

• Leaves thinning out, turning yellow, or wilting
• D-shaped exit holes created by the beetles
• Peeling bark and bark loss
• Shoots growing from the roots or trunk, “often with larger-than-normal” leaves
• Canopy loss
• Extra woodpecker presence and activity

The larvae of the pest eat the tree pulp under the bark. When this happens, you may see bark loss as they continue to eat and grow. When the adults exit the trunk, though they’re tough to spot, they will make a D-shaped hole in the bark. The Adult beetle will then start to destroy the tree’s canopy.

“I need to remove around 50% of the infested trees I encounter. Early detection and treatment will significantly increase the chance of the tree’s survival and reduce the chance of spreading the infestation.”
— Craig Small, ISA-Certified Arborist and Owner of Craig’s Tree Service

Treat Ash Trees Early With a Systemic Pesticide

Systemic pesticide treatments are an effective way to control the pest during its most destructive phase. These treatments target the larvae tunneling in the tree and kill the larvae as they eat the tree pulp. Craig’s Tree Service provides this treatment via a trunk injection, which delivers the pesticide directly into the tree’s vascular system. This treatment will need to be done every two years.

“Once branches begin to die, insecticides may no longer prevent damage and death. Detecting vulnerable trees early gives arborists and others more opportunities for intervention,” the USDA Forest Service shared.

Homeowners should consider the cost of treatment and value of the tree versus the cost of removing an infected tree. Discuss the current health of all of your trees with an ISA-certified arborist at Craig’s Tree Service today to establish a plan of action for your Ash trees.