The Mammoth Jack Stock was developed in the United States in its early years by George
Washington. He had received two Spanish Jacks which were used as studs. Later on the
Andalusian, Maltese, Poitou, Majorcan and the Catalonian were used in developed the breed. From these crosses,
breeders selected desirable traits which are now represented in the Mammoth Jack Stock.
The Mammoth Jack Stock has a distinct dark brown color of fur with white in the muzzle
and underbelly. It is tall, with the male standing around 56" while the female is
54". The weight of the Mammoth Jack Stock has range between 900-1200 pounds. Its purpose
is to produce draft mules or for agricultural work.