This deciduous shrub grows to 8 ft tall, often wider than tall. The stems are notable for their four corky ridges or "wings". The word alatus (or alata, used formerly) is Latin for "winged", in reference to the winged branches. These unique structures develop from a cork cambium. deposited in longitudinal grooves in the twigs' first year, unlike similar wings in other plants. The flowers are greenish, borne over a long period in the spring. The fruit is a red aril.
The red aril is an extra covering over the seed.