News and Activities

Effects of Forestry Herbicides on Trout Early Life Stages

Date Posted: December 1, 2005

The Service's Montana Field Office (MTFO) entered the second year of an investigation entitled Effects of Forestry Herbicides on Early Life Stages of Bull Trout and Rainbow Trout. This work will increase understanding of the risks of forest herbicides to bull trout. Herbicide application is currently the most effective management tool the US Forest Service has against invasive noxious plants.

The results of this investigation will provide information needed by Service Endangered Species biologists working with the U.S. Forest Service and the Bureau of Land Management on their weed management plans. Acute and chronic toxicity testing have been completed on commonly used forestry herbicides. Initial monitoring efforts of herbicide runoff in surface waters proved difficult. The Service is currently working with the USGS Columbia Environmental Research Center to find a way to monitor forestry applied herbicides in surface waters.


USFWS Mountain-Prairie Region

USGS Columbia Environmental Research Center

Last updated: June 12, 2015