Proper Timing of Trunk Injections for Emerald Ash Borer
Written by: Keith Glaznap, Certified Arborist WI-0678A
When should my ash tree be treated? This question is one of the most common that we hear. It sounds so simple and yet it is actually a very complicated question. There are many variables affecting it and the answer can quickly become entangled in a web of more questions.
Some of the basic variables that we must consider are the time of year, temperature, and soil moisture. Then there are more complicated variables that can lead to confusion among the general public. Some examples would include the different treatment methods available, the products available, and whether or not your ash tree has been treated before. Others could include the literally thousands of different articles on the internet, the yearly evolution of the research, and the growing number of different companies that offer EAB treatment programs.
As a Wachtel Tree Science client you can take comfort in knowing that all of our treatment programs are modeled after the most recent research available. This research reveals what the best products are, what the best treatment methods are, and what time of year these products are most effective.
We treat our client’s ash trees using a trunk injection containing Emamectin Benzoate. This treatment process usually begins in late June or early July depending on the weather. According to university research, most EAB larvae begin actively feeding in ash trees around mid-July in this part of the country. This means that our treatment timing coincides with the time frame that most EAB larvae are actively feeding on ash trees.
I recently had an email discussion with PJ Liesch about application timing for EAB when using trunk injections containing Emamectin Benzoate. For those that may not know, PJ serves as the director of the UW-Madison Insect Diagnostics Lab in addition to being an instructor with both the Wisconsin Master Gardener program and the Wisconsin Pesticide Applicator Training program. PJ has graciously let me share some of his comments in this article.
Given that we field a lot of questions about proper timing of EAB treatments I asked PJ if he could comment on what he thought about the timing of trunk injections with products containing Emamectin Benzoate. An excerpt of his comments are as follows:
“However, the Emamectin Benzoate products are very long lasting and will protect trees for at least 2 years. With that said, treatment timing isn’t as critical with those products. Some larger cities are treating thousands of ash trees with trunk injections. Due to the sheer number of trees in those municipalities, city crews have to make injections throughout the spring and summer just to make it to every tree over time.”
At Wachtel Tree Science we understand that there is a very large timing window when using our product of choice. Given this we deliberately target a window when ash trunk tissue is at the least risk of injury. This also happens to be a time when the treatment will be most effective and efficient. Simply put, our treatment time frame will offer you the best results at the best value with the lowest risk to your tree.
So the next time that you are wondering when we might be planning to treat your ash tree please know that we have your best interest at heart. Your application will be administered exactly when it should be… right when your tree needs it the most. If you have any questions please do not hesitate to contact your Wachtel Tree Science arborist today as we are happy to help you in any way that we can!