The Wood Bison differs from the Plains Bison (Bison bison bison), the other surviving North American subspecies/ecotype, in a number of important ways. Most notably, the Wood Bison is heavier, with large males weighing over , making it the largest terrestrial animal in North America. The highest point of the Wood Bison is well ahead of its front legs, while the Plains Bison's highest point is directly above the front legs. Wood bison also have larger horn cores, a darker and woollier pelage, and less hair on their forelegs and beard.
In addition to the loss of habitat and hunting, Wood Bison populations have also been in danger of hybridizing with Plains Bison, and therefore......