Oregon Revised Statutes Remedies and Special Actions and Proceedings § 30.937

(1) No farming or forest practice allowed as a preexisting nonconforming use shall give rise to any private right of action or claim for relief based on nuisance or trespass.

(2) Subsection (1) of this section shall not apply to a right of action or claim for relief for:

(3) Subsection (1) of this section applies only where a farming or forest practice existed before the conflicting nonfarm or nonforest use of real property that gave rise to the right of action or claim for relief.

(4) Subsection (1) of this section applies only where a farming or forest practice has not significantly increased in size or intensity from November 4, 1993, or the date on which the applicable urban growth boundary is changed to include the subject farming or forest practice within its limits, whichever is later.