Xen- (prefix): Foreign or other. As in: 1  Xenoantigen -- An antigen that is found in more than one species.  Xenograft -- A surgical graft of tissue from one species to an unlike species, genus or family.
Diet. Snow Geese feed almost exclusively on plant material. During the breeding season, they eat many seeds, leaves, and roots of aquatic vegetation. The very young birds feed on invertebrates. Berries become more important in the fall. In winter, waste grain from agricultural fields has become a primary food source.
Flocks are especially large in winter and during migration. Snow Geese forage mostly by walking in shallow water or on land, usually in flocks that may include other geese. They rip vegetation from the ground and can cause damage to areas where there are large numbers of geese.