There are several insecticide options and modes of application available to ash tree owners and managers that decide to treat their ash trees for Emerald Ash Borer. University research has shown varying efficacy with different insecticides and treatment processes. Professionally applied systemic insecticides have been found to be more effective than homeowner applied soil drenches. Please read the documents below to decide which option fits your situation.
Controlling insects that feed under the bark of trees with insecticides has always been difficult because they spend most of their life where topical application of insecticides won't reach them. The use of systemic insecticides (insecticides that are carried through the vascular system of the tree) is the only effective way to control EAB. This treatment regime is realistic only for individual trees and would be cost prohibitive on an area-wide basis. Systemic insecticides can be applied as a soil drench, a soil injection, or injected directly into the trunk of the tree. The only formulations available over the counter for homeowners in New York State are soil drenches. Soil and tree injections in New York must be applied by professionals. All insecticides must be applied according to instructions on the product label. Please carefully read these instructions before applying the insecticide to your trees, it's the law!
One of the most important aspects of chemical control for EAB is that one treatment will not save your tree. Some insecticides are effective for only one year and others only for three. EAB may persist in your area for a dozen years or more; multiple applications of insecticides will be required to save your trees. Be certain to consider this in your management plan and talk with your professional arborist about this necessity before embarking on a particular treatment plan; missing a scheduled treatment may make your ash tree vulnerable to EAB.
Chemical treatments are realistically only for individual ash trees, not for forest-wide treatments. For woodlots, see Woodlot Management.
CAUTION: New York State residents can only use products labeled for use in NYS and have to work with certified pesticide applicators to apply restricted use pesticides. For the list of insecticides registered in New York and their application mode and frequency, see below or click here.
Insecticide Table for Emerald Ash Borer in New York," Cornell University, 2011. PDF. This chart describes pesticides registered in New York to be used in conjunction with the Integrated Pest Management document, "Insecticide Options for Protecting Your Ash Trees from Emerald Ash Borer."
"Insecticide Treatment of Ash Trees in New York for Emerald Ash Borer" Cornell University, 2011. Discussion of treatment scenarios by infestation level, when to begin treatments, and considerations for applications. Written by Mark Whitmore.
Safari 20 SG Insecticide is now available Use on EAN under New York Special Local Need (SLN) Label. Read full document here.
"Insecticide Options for Protecting Your Ash Trees from Emerald Ash Borer," North Central IPM Center, 2014. This bulletin includes answers to frequently asked Emerald Ash Borer questions, options for treating ash trees, insecticide options, effectiveness of insecticides for control of Emerald Ash Borer, and summary recommendations.
Additional documents to help your research your treatment options