The winged elm, Ulmus alata, is named after interesting cork-like projections that appear on both sides of its branches. These projections are somewhat like webbing and warts, and are known as wings. The tree is also known as cork elm and wahoo elm, with the name wahoo elm derived from the American Creek Indian word for this tree, uhawhu. Because of the cork-like projections on its limbs, the winged elm is a very easy tree to identify.
The winged elm is native to the southeastern and south-central United States. It is commonly found in woodlands only in mixture with other hardwoods, and it is not a major component of any forest type. It is the least shade-tolerant elm, growing rapidly only in the open. It prefers moist, fertile, well-drained soil but it
may be found in flood plains as well as dry, rocky ridges. Because it is an attractive tree that is adaptable to a wide range of conditions and needs little care to grow, it is sometimes found in parks and along streets. However, because it is susceptible to Dutch elm disease, landscape use is less frequent than it has been in the past.
Winged elms usually grow to a height and breadth of 40 to 60 feet. Trunks rarely exceed 2 feet in diameter, as trees may only grow 2 to 2.5 inches in diameter in 10 years. Trees have a rounded, open crown with pendulous branches rising up and then sweeping toward the ground. In poor, dry areas the tree is stunted and 
gnarled, but in old growth forests such as the Fernbank Forest in Atlanta, Georgia winged elms may attain heights of as much as 128 feet. Winged elms commonly have multiple trunks, and most consider that these trunks and the narrow-crotched branches should be pruned when young to form a more desirable structure. Trees look very open and lanky following pruning, and may not look great at that stage. Trunk bark is brownish-gray, with tight vertical plates, flat ridges, and curvy furrows. Mature trees have flat plates separated by shallow fissures. Bark on limbs have corky wings and warts extending the limb’s entire length.
Leaves on the winged elm are simple, alternate, and oblong-lanceolate to narrowly 
elliptical. They are doubly serrated on the margins. They are generally less than 2½ inches long and ¾ inches wide. Leaf upper surfaces are dark green with a smooth surface, and under surfaces are paler green and rougher due to hairs. Leaves turn bright yellow in the fall.
Flowers on the winged elm are perfect having both female and male parts, and they are produced before leaves develop in March and April. They are brown or burgundy, and borne on long extensions called pedicels. They are wind pollinated. The fruit is a hairy, flat, reddish to greenish samara that is about 1/3 inches long. It is surrounded by a narrow wing, and is wind or water dispersed by the end of April. The tree has a reddish appearance when fruiting.
There is minimal commercial use for winged elm, despite desirable characteristics of the wood such as hardness, resistance to splitting, and ease of bending. This is due to economic considerations of the tree’s slow rate of growth, the tree’s commonly small trunk size, and the tree’s susceptibility to Dutch elm disease. However, the wood is used to make high quality hockey sticks. It is also used to make furniture, hardwood trim and flooring, boxes, crates, and bent pieces on rocking chairs. The fibrous inner bark is used to make baling twine and rope. The wood pulp is used in making paper. Native Americans have used the tree’s inner bark to treat diarrhea and to ease childbirth. The tree is useful in landscaping parks, streets, and buildings. The winged elm can be a very useful tree.
The winged elm I found at work had never been pruned, so it had a split trunk. I found it a naturally attractive tree, and a great complement to the diversity of trees on campus.
