Emerald Ash Borer Update by Dave Scharfenberger

Will Emerald Ash Borer (EAB) be the end of unprotected ash trees in Wisconsin, the Midwest and the entire US? No one knows that answer but it could be “yes”! Locations of EAB have continued to increase in southeast WI. A common fact emerges when looking at other areas that are now dealing with full-blown infestations (Indiana, Ohio & Illinois) is that there has always been a significant increase in discoveries after the initial find. We are just beginning that period. This means continued bad news for ash trees! So, we feel it is important to get everybody caught up on what is new with EAB and where we are at with this pest.

 Where are we?: EAB is very likely better established than anyone knows. Ash trees will continue to be at increasing risk.

 What you should do?: Evaluate your ash trees and decide if any are important enough (and healthy enough) to keep. Consider planting a tree to replace your ash. Work with your Wachtel Tree Science Certified Arborist.

 What are your options?: 1.) Treat to protect. 2.) Plant nearby and remove when infested. 3.) Remove now and replant now. 4.) Do nothing but be sure to monitor so the tree does not become a hazard. Dead trees are more expensive to remove.

 How to protect?: 1.) Yearly Imidacloprid soil systemic insecticide has a great track record and does not injure the tree. 2.) Tree-Age trunk injections are showing to be a good choice but do injure trees with injection sites. Protection with insecticides is great for key trees but it does mean continuing costs for future treatment.

 What is new?: 1.) Some Imidacloprid products have a higher rate for larger trees. 2.) Tree-Age trunk injection may be protecting up to three years.

 When to start?: Now! If you decide you want to protect your tree, it is important to start before trees become infested. If you wait until after they are infested, control will be compromised. Planting now will get that new tree growing.

 Are there some good opportunities?: Here is your chance to plant more variety in your landscape so future invasive insects or diseases do not impact you as hard.

 Is there one perfect answer?: No, work with your Certified Arborist and budget to determine what is best for you.

 What am I missing?: Do not ignore important maintenance on key trees of other species. Remember that if your ash die, the other trees will be even more important to you! Keeping them healthy will be very important to your long-term landscape!

 Who to call?: As always, work with your Wachtel Tree Science Certified Arborist.

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