ORS § 547.495
All drainage districts organized pursuant to the provisions of the Drainage District Act shall have a lien on all crops grown on lands within such districts for that portion of the annual charges or assessments, levied against the lands on which the crops are grown, or imposed upon the owners or occupants of the land, that are for maintenance and operation of such districts. This lien shall be prior to every other lien, mortgage or encumbrance on the crop, except labor liens now granted by the laws of Oregon and crop mortgages given by landowners in the district to federal or state loaning agencies set up by the federal government or the state to secure loans, the proceeds of which are used in the production of crops of such landowners, provided such loaning agencies certify to the districts that such loans cannot otherwise be made to the landowners. The lien shall be in addition to any other lien securing the payment of maintenance and operation charges or assessments, and shall be a continuing one and shall bind the crops after, as well as before, they have been gathered; provided, that the share of any tenant who has leased such lands on a share rent basis shall be exempt from the lien to the extent of three-fourths of the entire crop.
ORS 547.495