If your area has emerald ash borers, you need to know what to look for and how to protect your tree before it's too late. Two common emerald ash borer treatments used are soil treatments (drenches or injections) and trunk injections.
Here are the basics of both these treatments.
The emerald ash borers don't live in the soil, so treating the soil may sound like an odd choice. However, what happens is that the tree's roots suck up the treatment, allowing it to get inside the tree's tissues naturally.
The types of substances used for soil treatments are called systemic insecticides. These are insecticides that spread throughout the tree so that if a targeted insect (such as an emerald ash borer) tries to eat any of the tree's tissues, it ends up ingesting insecticide as well.
Your tree experts will either apply a liquid treatment directly to the ground or inject it just beneath the surface of the soil. The majority of a tree's roots are typically found in the top foot or so of soil, so the treatment doesn't need to be injected very far down.
Instead of waiting for the tree to take up the systemic insecticide on its own, you can also have your tree expert inject the pesticide directly into the tree's trunk for even faster results. When performed by an expert, this procedure inserts the treatment into the part of the trunk that carries water and nutrients throughout the tree (similar to the purpose of blood vessels).
The downside of a trunk injection is that the tree then has small wounds that will likely callus over and heal but that are also at some risk for infection by diseases. The upside is that in addition to working faster than soil treatment, trunk injections avoid contaminating the soil and can work even if your tree expert deems the soil in the area unworkable for a soil treatment.
Don't confuse a trunk injection with another type of trunk treatment that involves spraying the product on the outside of the trunk. While less invasive than an injection, this type of treatment isn't considered as reliable, although theoretically, it can be effective.
As you can see, systemic insecticides can be applied effectively either at the roots or at the base of a tree's trunk to treat emerald ash borers. For more details on the process or an estimate of how much each one would cost, contact your local tree experts today.