The county assessor or the assessor's deputies shall:

1. 1. Make an on-site inspection of twenty-five percent of the property classified as being used for agricultural purposes each year.
2. 2. Make an on-site inspection and appraise all of these properties within every four years.
3. 3. If the county assessor or the assessor's deputy determines that the property does not meet the criteria for agricultural classification, notify the property owner pursuant to section 42-12156.