Oregon Revised Statutes Counties and County Officers § 209.090

(1) The county court shall procure from the Bureau of Land Management a copy of the field notes and plats of all surveys and resurveys of public lands of townships, sections, Donation Land Claims, mineral claims, homesteads, meander lines or other similar surveys lying within its county. These shall include copies of the official plats and field notes of the survey and shall be filed in the office of the county surveyor.

(2) Copies, certified by the county surveyor, of copies of such field notes or plats filed in the office of the county surveyor by the county court shall be prima facie evidence.