As used in ORS 733.510 to 733.780, “improved real property” means:
(1) Farmland used for tillage, crop or pasture;
(2) Real estate on which permanent improvements, or improvements under construction or in process of construction, suitable for residence, institutional, commercial or industrial use, are situated; and
(3) Real estate to be developed for the use or uses set forth in subsection (2) of this section on which improvements, or improvements under construction or in process of construction, such as streets, sidewalks, sewers and utilities which will become an integral part of such development, are situated.