Oregon is the nation’s third-leading producer of peppermint, harvesting approximately 840,000 pounds with a crop value of $28.7 million in 2022. But pests like mint root borer and variegated cutworm threaten crop yields and grower profitability.
The Mint Pest Alert Newsletter supports Oregon growers with timely, science-based recommendations
For years, growers relied on organophosphate insecticides such as chlorpyrifos to manage these pests. However, chlorpyrifos was phased out for use on food crops by the U.S. Environmental Protection Agency at the end of 2022 due to concerns about human health impacts.
A newer product — chlorantraniliprole (marketed as Coragen and Vantacor) — offers effective control and fewer risks to non-target organisms. However, timing is critical. Applications must align with specific pest development stages for the insecticide to be most effective.
To help growers optimize spray timing, the Oregon State University Extension Service developed the Mint Pest Alert Newsletter in 2014. This decision support tool combines weather-based insect development models with field trap data to predict the best treatment windows.
During the growing season, growers in the Willamette Valley, Central Oregon and northeastern Oregon receive weekly email updates. The newsletter uses data from five regional weather stations to provide localized recommendations and includes integrated pest management guidance.
Growers report significant benefits. In a recent survey:
- More than 50% of respondents reported using Coragen or Vantacor
- 50% said the newsletter improved pest control
- 42% reduced the number of insecticide sprays
- 33% increased reliance on chlorantraniliprole
- 17% reduced use of broad-spectrum insecticides
Additionally, 84% said the newsletter improved their understanding of insect development and influenced their choices about insecticide and application timing.
According to grower estimates, the newsletter saved an average of $28.33 per acre in pest management costs — totaling an estimated $453,000 in statewide savings across Oregon’s mint acreage.
For more than 10 years, the Mint Pest Alert Newsletter has supported Oregon growers with timely, science-based recommendations — improving pest control, reducing input costs and contributing to a more sustainable mint industry.
