The Oregon Forest Practices Act requires re-planting of new trees within two years of harvest, and they must be free-to-grow within six years. That means the young trees must be able to outcompete neighboring grass and brush. When planting after harvest, foresters sometimes use herbicides to control weeds, brush and invasive species that compete with new trees for sunlight, nutrients, and water. They are applied sparingly in the first few years so that trees can be free to grow on their own for another 40 years.
Herbicide applications are conducted under heavy, science-based regulation and have a strong track record for safety. The law is very clear on the safety standards for application near adjacent landowners and near streams. Where there are violations of this law, the state has and should take action to hold people accountable.
Testing in Oregon has not found unsafe levels of herbicides on lands or streams surrounding applications. A 2012 Eugene Water and Electric Board study looked at eight years of pesticide monitoring in the McKenzie River Basin and concluded that forestry pesticides were rarely detected and, when present, were not at levels that would be harmful. The Oregon Department of Environmental Quality also conducted two water-monitoring studies in the Siuslaw watershed and along the North Coast. Neither study found pesticide residue at levels that would be a risk to the environment or public health.
The safety of local communities and residents is paramount in herbicide applications. The Oregon Department of Agriculture has only received 11 complaints involving aerial application of herbicides in forestry over the last four years. Only three of those complaints resulted in penalties. According to three years of Oregon Health Authority reporting, only one of 178 reported cases of pesticide illness was due to forestry. When there is a violation of law in herbicide application, however, we fully support investigations and enforcement to ensure public confidence in forest practices.