Leaves are usually narrow and wedge-shaped at the base. Side buds curve away from the twig. The third bud scale is nine-tenths as long as the bud. Buds are small and viscid. Twigs are glabrous and slightly angled.
Leaves are usually broad and rounded to wedge shaped at the base.
No gland is present at base of the leaf blade. Side buds do not curve away from the twig. The third bud scale is not over three-fourths as long as the bud. Leaves are usually square or nearly heart-shaped at the base. Twigs are slightly angled.