2024 Project Update

2024 Project Update

IPPM entered its eighth year of treatment for the Japanese beetle (JB) eradication program in the greater Portland area. Treatment for JB occurred from April to July. Most properties were treated with a single application of the granular larvicide Acelepryn® G (Chlorantraniliprole) on lawns and ornamental planting beds. This season the granular treatment area included approximately 4,500 properties spread over approximately 1,300 acres. Successful eradication of several small pockets of beetles allowed the treatment area to be almost half the size it was in 2023. 

 A large infestation in and around a single farm have made up for a majority of Japanese beetle trap catches since 2022. Beetles were first detected on the farm in 2020. IPPM was not able to treat until 2023. ODA treated the edible plants with a product called Altacor® (Chlorantraniliprole), which attacks JB at both the larval and adult stages. Since the infestation was so severe at the farm, two treatments were conducted in 2024: one larval treatment and one supplementary foliar spray treatment.  

 In 2024, ODA placed 10,272 traps throughout the state in all 36 counties. All JB traps were set by June 15th, and the last traps were removed in October. ODA trapped 5,467 Japanese beetles, a 15% decrease from the number of beetles trapped in 2023 (see table 1). However, most trap catches (~76%) were isolated to the one blueberry farm. Only 1,348 beetles were trapped outside the blueberry farm, similar to the numbers trapped outside the blueberry farm in 2023 (1,069 beetles). So, while the total number of beetles trapped increased from 2022, trap catch numbers continue to shrink in areas ODA has been treating. The treatment area will continue to shrink next season, as the planned 2025 map is 950 acres or a 30% decrease from the 2024 map.  The treatment area shrinking in size shows that ODA is nearing its goal of eradication, as we have eliminated many small pockets of JB throughout the Portland area.