Spring 2015 - The Lion Sleeps Tonight

By Tony Arnoldi, Board Certified Master Arborist

…but maybe not tomorrow night.    The warm temperatures we have had lately have been long anticipated—finally we can get outside and enjoy the rite of spring—blooming spring bulbs, then shrubs, and next flowering trees and perennials join in! It’s time for long walks, Sunday drives and maybe the year’s first visit to the custard stand.

Something else is stirring also. The warmth causes the dormant Emerald Ash Borers’ metabolism to increase. With its blood pumping faster, the urge to chew its way through the wood to the outside world grows stronger. Soon, very soon…then it can mate, find another suitable ash on which to lay its eggs, and enjoy the rest of the summer in the sun. They do love the warm sun…

Another name for it could be the Ash Lion. It is responsible for so many millions of dead ash already, and its ravenous appetite is far from abated. Eventually, all unprotected ash trees will be victims of its onslaught.

But Ash trees can be protected from this beast. Although there have been several methods used with success in previous years, now that their numbers have grown so much only one material has proven to be capable of keeping an ash tree effectively protected for the long term. That material is an insecticide called Emamectin Benzoate. It is the crucial active ingredient in several trade names for this product. We are using Arbormectin, formerly we used Tree-age (both are Emamectin Benzoate products). We inject this into the trunk in summertime to achieve 2 years of control. Research is showing it is better than 95% effective and is the only material with this claim. It must be done every 2 years to sustain protection, but if done correctly and uninterrupted, will enable chosen ash trees to grace our landscape indefinitely.

Because this protocol requires repeated use of injection technology, great care must be given to correctly select, space, and administer the injection sites over the years. To help this effort we have developed a technique and system that requires significantly smaller-diameter injection holes compared to how many other companies are doing it. This minimizes wounding and enables continuation of the protection. It is a major reason why experienced applicators with advanced techniques will be able to keep ash protected for a long duration. With so many different people “jumping in” to take advantage of the surge of work, it pays to be careful when selecting a caregiver.

I have switched the vast majority of my own client base from the soil-injected insecticide imidacloprid that we had been doing over the last several years, to the Emamectin Benzoate products. This switch happened over the last 2 years. Only a few accounts remain using the “old” method for various reasons, but I am working to get these last ones switched over as well.

The research scientists tell us that the population “explosion” is before us as we enter the exponential growth portion of the Emerald Ash Borer population growth curve. Given where we are on the curve, we know that there is not much time left to select or add any ash for protection. Once the borers enter an ash tree, it is not long before that tree is too damaged to be able to save. But there remains a great many beautiful ash trees that could be saved. I hope that many will be allowed to escape the fate that awaits them. 

Given the great amount of time it takes to grow a large magnificent tree, perhaps now is the time to intervene and enable an ash to be enjoyed by you, your children and your grandchildren for years to come. Call your Certified Arborist to help with the selection process, then good results will be achieved. Did I just hear roaring in the distance…?

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