This native shrub is up to 20' tall with an irregular rounded crown, forming a central trunk up to 6" across. Sometimes multiple branches are produced from the ground, instead of a trunk. The bark of the trunk and larger branches is grey and slightly rough. Smaller branches have bark that is more smooth and gray-brown. Alternate trifoliate leaves are produced on new stems that are green, terete, and usually hairless. The leaflets are 2-4" long and 1-2" across; they are narrowly ovate to ovate, smooth or slightly toothed along their margins, and sessile. The leaflet upper surfaces are medium to dark green, hairless, and shiny, while the lower surfaces are pale green and hairless (rarely pubescent). The bases of the leaflets are wedge-shaped, while their tips are slender and pointed. The petioles of the trifoliate leaves are light green, terete, hairless, and about 2-6" long. Occasionally, umbel-like panicles of flowers are produced that are 2-3" across. Wafer Ash is monoecious, often producing male, female, and perfect (bisexual) flowers on the same shrub. Regardless of gender, individual flowers are a little more than ¼" across. Perfect flowers have 4-5 petals, 4-5 sepals, 4-5 stamens, and a single flattened pistil that is green and obcordate-orbicular in shape. The petals are whitish or yellowish green and narrowly lanceolate-oblong. Male flowers lack the central pistil, while female flowers lack stamens. The slender pedicels of the flowers are light green and hairless. The blooming period occurs during the late spring and lasts about 2 weeks. Each flower with a pistil develops a flattened fruit that is broadly winged along its margins and about ¾1" across. The winged margins of the fruit have a reticulated network of fine veins, while its center contains 2-3 seeds. Immature fruits are green, but they become light brown at maturity. The root system is woody and branching. Vegetative offsets from underground runners are not produced.