Ulmus alata

Ulmus alata, the winged elm or wahoo, is a small- to medium-sized deciduous tree endemic to the woodlands of the southeastern and south-central United States. The species is tolerant of a wide range of soils, and of ponding, but is the least shade-tolerant of the North American elms. Its growth rate is often very slow, the trunk increasing in diameter by less than 5 mm (3⁄16 in) per year. The tree is occasionally considered a nuisance as it readily invades old fields, forest clearings, and rangelands, proving particularly difficult to eradicate with herbicides.

Description

As its common and scientific names imply, winged elm is most easily recognized by the very broad, thin pair of corky wings that form along the branchlets after a couple of years. The tree generally grows to a maximum height and breadth of about 13 m × 13 m (43 ft × 43 ft), although on fertile alluvial soils such as those of the Mississippi River Delta, some specimens have reached double this height (see 'Notable trees' below). The crown can be either rounded or pyramidal; the branches are pendulous. The leaves are comparatively small for the genus, less than 6.5 cm (2+1⁄2 in) long and less than 2.0 cm (3⁄4 in) broad, oblong-lanceolate to narrowly elliptic, thin in texture, and smooth above with serrate or doubly serrate margins. The leaves turn bright yellow in Autumn. The wind-pollinated perfect apetalous flowers are borne on long pedicels in March and April before the leaves appear.