(at issue were whether various items of plaintiff's personal property subject to state personal property tax; plaintiff operated a farm and a pumpkin patch of about 16-18 acres that attracted approximately 50,000 people to the farm; wheelbarrows used to transport pumpkins from field to store used exclusively for transporting pumpkins and qualified as "farm machinery" exempt from personal property tax; however, sternwheelers, trains, train cars and traffic safety equipment not entitled to exemption because such items not used primarily in harvesting activities).