Our impression was that you aren't "collecting" unless you have at least 100 tractors! When one local collector was asked how many  tractors he owned, his response was two. We quickly learned that two meant two barns full, and they weren't small barns. Monday, March 11 was our travel day but we squeezed in a tour of the Deere World headquarters located outside of Moline. The museum contained more antique John Deeres as well as new agriculture, industrial and lawn-garden products.  With a bonus trip to inner Chicago and some cultural awareness (don't ask Tom Jensen about this!)  the  van got us to the airport on time for our return flight home. ajohnson