35 ILCS 200/1-60
When used in connection with valuing land and buildings for an agricultural use, any property used solely for the growing and harvesting of crops; for the feeding, breeding and management of livestock; for dairying or for any other agricultural or horticultural use or combination thereof; including, but not limited to, hay, grain, fruit, truck or vegetable crops, floriculture, mushroom growing, plant or tree nurseries, orchards, forestry, sod farming and greenhouses; the keeping, raising and feeding of livestock or poultry, including dairying, poultry, swine, sheep, beef cattle, ponies or horses, fur farming, bees, fish and wildlife farming. The dwellings and parcels of property on which farm dwellings are immediately situated shall be assessed as a part of the farm. Improvements, other than farm dwellings, shall be assessed as a part of the farm and in addition to the farm dwellings when such buildings contribute in whole or in part to the operation of the farm. For purposes of this Code, "farm" does not include property which is primarily used for residential purposes even though some farm products may be grown or farm animals bred or fed on the property incidental to its primary use. The ongoing removal of oil, gas, coal or any other mineral from property used for farming shall not cause that property to not be considered as used solely for farming.
35 ILCS 200/1-60