This summer, Facilities Management (FM) Outdoor Services and Housing Facilities Services (HFS) will continue to engage in responses to the emerald ash borer (EAB) infestations in our campus trees. Integrated pest management (IPM) strategies used against this pest include the injection of insecticides directly into the trunks of threatened or infested trees.
Weather permitting, on or after June 15, and as part of the core campus treatments, staff will facilitate applications of the following insecticides:
- TREE-age (Emamectin Benzoate) to 128 ash trees on both main and east campuses. TREE-age has EPA Reg. No. 100-1309-74578.
Weather permitting, on or after June 15, and as part of the product trial treatments, staff will facilitate applications of the following insecticides:
- TREE-age (Emamectin Benzoate) to 14 ash trees on East Campus. TREE-age has EPA Reg. No. 100-1309-74578.
- Boxer (Emamectin Benzoate) to 14 ash trees: eight trees at Colorado Avenue and Discovery Drive and six trees at the Space Science Building. Boxer has EPA Reg. No. 69117-12.
- TreeAzin (Azadirachtin A and B) to 14 ash trees: eight trees at Colorado Avenue and Discovery Drive and six trees at the Space Science Building. TreeAzin has EPA Reg. No. 82996-1.
These applications will occur on up to 170 trees, including 42 that are part of a product trial being conducted in collaboration with faculty and students from Colorado State University, the city of Boulder forestry division, ArborSystems and Arborjet. These trees are located on our main and east campuses in areas that are managed by the Campus General Fund, Real Estate Services, Parking & Transportation Services, and Housing & Dining Services.
Emerald ash borer infestations were confirmed on CU Boulder property in 2014. At that time, there were more than 700 maintained ash trees listed in the campus tree inventory. The total number of trees to be treated this summer represents only about 24 percent of that inventory.
The product trial includes 56 trees in all, 42 that receive treatments (some on alternating years) and 14 trees in a control group that receive no insecticide treatments. Forty-two of the trial trees are receiving treatments this year. The study is an effort to ascertain effective responses to the burgeoning EAB infestation in Boulder, as well as to support forestry and entomology research. All trees in the trial are on East Campus.
These trees are infested by or are directly adjacent to infestations of emerald ash borer. All applications will be performed by trunk injection, directly applying the insecticides into the sapwood of the tree. This method delivers the product to the target insects, greatly minimizing exposure to non-targeted animal or plant species.
Professional applicators, licensed by the state of Colorado, will be conducting the trunk injections. As a further effort to ensure the highest standard of health and environmental protection, FM and HDS staff will accompany the contracted applicators to ensure only predetermined locations receive a treatment and all necessary precautions are taken to avoid non-target impacts.
Guidelines for pesticide use are generally described in the campus pest control policy. These applications are one of many tools used as part of an integrated approach to landscape management. The trees will continue to receive supplemental watering and cultural care and will be monitored closely for treatment efficacy and overall health.
Staff will also be placing yellow application notice flags at the base of all trees, indicating where the application was made. Law requires these flags remain in place for 24 hours after an application has been made. In the interest of keeping the campus community informed, staff will leave these flags in place for one full week after the application occurs.
Please do not hesitate to contact Facilities Management if you should have any questions or concerns. You may reach Outdoor Services Assistant Director Don Inglis at 303-735-6311 or donald.inglis@colorado.edu. Or you can reach Environmental Services Assistant Director Robert Lenahan at 303-735-3627 or robert.lenahan@colorado.edu.
