Doodlebug is the colloquial name for a home-made tractor made in the United States during World War II when production tractors were in short supply. The Doodlebug of the 1940s was usually based on a 1920s or 1930s era Ford automobile which was then modified either by the complete removal or alteration of some of the vehicle body.
These contraptions went by many names: Friday Tractors, Scrambolas, Jitterbugs, Field Crawlers, and many others as well as the most common, The DoodleBug, which was a nickname for the aftermarket tractor kit made by David Bradley "The old DB". Initially the idea of the homemade tractor came from several catalog and implement companies in the mid 1920's to the mid 1930's such as New Deal, Peru Plow Co., Thrifty Farmer, Sears, Montgomery Ward, Pull Ford, and Johnson Mfg Co.
The conversion kits were expensive, some as much as $300 and farmers, hit hard by the Great Depression were a resourceful lot. Magazines such as Popular Mechanics & Mechanics Illustrated provided instructions for building a "Handy Henry" from that "old Ford sitting in your back yard, using simple tools anyone would have." The cost to build a "Handy Henry" made from an old Model T car or truck was about $20 according to the 1936 edition of the Handy Man's Home Manual, and this provided a serviceable vehicle with rubber tires, a big truck rear end and two transmissions to make up for the gear reduction that the kits came with.
These Doodlebugs were used to plow, hay, haul logs, and pull out stumps. To do all this, the doodlebug needed good ground clearance for use in any conditions, going under trees, and climbing almost any terrain. For protection they had a hood, cowl radiator, a small seat. Some were configured with a small truck bed, and most had a hitching point front and rear to tow with.
The preservation of examples of the Doodlebug tractor has become popular in New England and upstate New York where there are several clubs holding monthly meet-ups in the summer months to put their contraptions to the test by pulling large stone boats in a tractor pull.