Jim Criger of Springfield, MO, designed and built a number of 8 x 16 feet Homemade Portable Pig Tractors. They're fitted with tow hooks in front and back so they can be moved by pickup truck or utility vehicle to fresh ground, using tow straps. The sides are wire cattle panels fitted into 1/8-inch angle iron then welded to a bottom frame, which is made of 6-inch-wide flanged beams in front and back and attached to skids made from 2 x 2 inch angle iron that Criger notched and bent up at each end to facilitate pulling. The front of the tractor has a full door with a built-in half door that opens upward. Treated plywood at the back and halfway across the top provides shelter from the elements. A 55-gallon plastic water barrel is mounted on the top plywood, with a piece of garden hose running to a pair of automatic water nipples on one of the wire panels. The frame's front beam doubles as a feed trough. Criger-built pig tractors are available for purchase.