Overview: There's an acre of wheat to cut and collect. This semifinal Junkyard challenge sends the competitors down to the farm to see who can build the best mower. One team turns a taxicab into a take-no-prisoners lawnmower, while their opponents turn a pickup truck into a harvester. Amid lots of smoke and chugging, both teams' machines "buy the farm." The winning machine is an impromptu scythe made out of a foot of metal.