ORS § 226.350
After so much land and property referred to in ORS 226.330 as is needed has been appropriated for public squares, parks or playgrounds, the municipal authorities of the city may by ordinance authorize the sale of the remainder of such land or property and impose such restrictions in any deed of resale as may be deemed necessary or proper. The ordinance shall specify correctly and describe the land or property to be sold, and the restrictions in regard to the use thereof. The restrictions shall fully insure the protection of the public squares, parks, or playgrounds, their environs, the preservation of the view and appearance, light, air, health or usefulness thereof, whenever the council shall by ordinance determine thereon and which are to be imposed and inserted in the deed of resale.
ORS 226.350