Oregon Revised Statutes Revenue and Taxation § 321.580

If any taxpayer neglects or refuses to make a return required to be made by ORS 321.005 to 321.185, 321.560 to 321.600 or 321.700 to 321.754, the Department of Revenue is authorized to determine the tax due, based upon any information in its possession or that may come into its possession. The department shall give the taxpayer written notice of the tax and delinquency charges and the tax and delinquency charges shall be a lien from the time of severance. If the tax and delinquency charges are not paid within 30 days from the mailing of the notice, the department shall proceed to collect the tax in the manner provided in ORS 321.570.