Oregon Revised Statutes Revenue and Taxation § 307.394

(a) Farm machinery and equipment used primarily in the preparation of land, planting, raising, cultivating, irrigating, harvesting or placing in storage of farm crops;

(b) Farm machinery and equipment used primarily for the purpose of feeding, breeding, management and sale of, or the produce of, livestock, poultry, fur-bearing animals or bees or for dairying and the sale of dairy products;

(c) Machinery and equipment used primarily to implement a remediation plan as defined in ORS 308A.053 for the period of time for which the remediation plan is certified; or

(d) Farm machinery and equipment used primarily in any other agricultural or horticultural use or animal husbandry or any combination of these activities.

(2)(a) Items of tangible personal property, including but not limited to tools, machinery and equipment that are used predominantly in the construction, reconstruction, maintenance, repair, support or operation of farm machinery, and equipment and other real or personal farm improvements that are used primarily in animal husbandry, agricultural or horticultural activities, or any combination of these activities, are exempt from ad valorem property taxation.

(b) An item of tangible personal property described in paragraph (a) of this subsection is exempt from ad valorem property taxation only if the person that owns, possesses or controls the item also: