Weed Management

The City and its contractors (Including Trout Mountain Forestry and Institute for Applied Ecology(IAE)) spray invasive and non-native plants in the Corvallis Forest annually. IAE sprays as part of a long term meadow restoration at Old Peak Meadow (Click here to learn more about that project). Weed management is reported in the annual Forest Activity Report. 

2025:

Invasive false brome and Scotch broom were treated in the spring 2025 to reduce their presence in the Corvallis Forest. Targeted herbicide application was used primarily in select roadside locations,where available sunlight allows growth of the invasive plants. All application was done by applicators licensed by Oregon Department of Agriculture following EPA and Oregon Department of Forestryrules for forestry chemicals.

Invasive Himalayan blackberry was cut using brush saws in July 2025. This mechanical treatment, intended to reduce total leaf area of the plants, was timed to allow re-growth of the plant prior to a targeted herbicide treatment planned for fall of 2025. Invasive Himalayan blackberry was also mechanically removed in July 2025 from one of the Peacock Larkspur sites due to the woody vegetation overtaking the site; this site was not treated with any herbicide, and woody vegetation was removed after flowering was complete.

Control of invasive species is in alignment with the Forest Chemicals policy of the Corvallis Forest Stewardship Plan to "Minimize the use of pesticides in the Corvallis Forest," and the Native Vegetation and Invasive Species Policy to "Promote native plant communities, protect and restore special status species, actively control and monitor existing invasive species, and follow best management practices for minimizing the introduction and establishment of new invasive species in the Corvallis Forest."