ORS § 311.219
Notice shall be given to the person claiming to own the property or occupying it or in possession thereof of the assessor's intention to add the property to the assessment or tax roll under ORS 311.216 to 311.232 and to assess the property in such person's name. Where the assessor has reason to believe the property is either no longer in existence or is outside the county, the assessor shall give the notice to the owner or the person in possession on the assessment date of the year or years as to which the property was omitted. The notice shall be in writing, mailed to the person's last-known address. It shall describe the property in general terms, and require the person to appear at a specified time, not less than 20 days after mailing the notice, and to show cause, if any, why the property should not be added to the assessment and tax roll and assessed to such person.
ORS 311.219