All taxes, interest and penalties due and unpaid under ORS 321.005 to 321.185, 321.560 to 321.600 or 321.700 to 321.754 constitute a debt due the State of Oregon and may be collected, together with interest, penalty and costs, by appropriate judicial proceeding, which remedy is in addition to all other existing remedies. However, no proceeding for the collection of taxes under ORS 321.005 to 321.185, 321.560 to 321.600 or 321.700 to 321.754 shall be instituted after the expiration of six years from the date the taxes were due.
ORS 321.600