jamie: i meet bruce brock.ellow history buff, he and dave within way back. >> i was proud to be his friend. he was a good businessman, a good father, a good husband a great neighbor,e. jamie: i know coin collecting and cars but with trackers? >> these are reputation of the past that farmers and pharmaceuticallies, and -- farm, families and farm relations enjoy looking at. jamie: tractors are part of iowa's history in 1892down froehlich invented the gas power tractor in a tiny village about 300 miles east of here, it helps america become a agricultural giant. even though none of dave a 4 children tills the soil like he dhe shares his passion for tractors with his grandson alex. >> i can remember as young as 4 years old riding in the combine with my grandpa taking napping at floor. >> pretty soon the sheds are filled with old tractors in various states of repair, more than a hundred. jamie: did mom ever say no more tractors? >> not really, but i remember dad called the withtors his -- tractors his savings account