- The elm tree often forms a distinctive vase-shaped crown and grows to impressive size. It is distinguished from the similar-looking beech by its jagged-edged leaves with uneven bases. The bulk of the life cycle of most elm species occurs during late spring and early summer, when elms send winged samaras swirling to the ground. In the autumn, you can expect foliage changes from your elm as it sheds its leaves for winter. A few species produce fall flowers and seeds.
- Ravaged by Dutch elm disease, the American elm (Ulmus americana) is seen rarely today. Its leaves tend to be larger than the leaves of most other elm species. The leaves turn yellowish-brown as winter approaches, a color that the University of Connecticut's horticulture department describes as not particularly showy. Special cultivars of American elm, however, offer showier yellow foliage to add fall color to your yard.
- Contrary to its name, the slippery elm (Ulmus rubra) is distinguished from other elms by its hairy-edged and sandpapery leaves, hairy twigs and fuzzy leaf buds. The name comes from the slimy texture of the tree's inner bark. Like the American elm, the slippery elm produces flowers and seeds in spring. Autumn changes the tree's foliage to a pale yellow.
- Unlike its relatives, the lacebark elm (Ulmus parvifolia), an Asian import, produces its flowers in the fall, according to the Ohio State University Extension Service. The unusual flowering time makes this elm easy to distinguish from most others. Flowers open in late summer to early fall, and seeds develop as winged samaras in October and November. Their bright red color makes them stand out against the elm's foliage. According to the extension service, the lacebark elm also produces showier fall foliage than most of its relatives, with colors ranging from yellow to purple. Lacebark elms cannot always withstand the chilly autumn and winter temperatures common to the northern United States.
- The English elm (Ulmus procera) also completes most of its life cycle at the beginning of the year. When autumn comes around, however, the leaves -- noticeably smaller than those on many other elms--remain dark green and on the tree late into the fall. As autumn edges into winter, the leaves turn a yellow-brown similar to that of other members of the genus, and fall from the tree.
- As the name suggests, the native but rare September elm (Ulmus serotina) produces its flowers and seeds in the fall, with flowers opening in September and maturing into light green samaras from late October to early November. The samaras ripen to a light brown color before dropping from the tree, where they provide a winter food source for birds and squirrels.