Willow oak (Quercus phellos) is a large deciduous tree easily distinguished by its leaves which are very similar to certain willows (Salix). Leaves are very narrow with a short stalk, wavy along the margins (edges) and appear very willow-like. Leaves stand out stiffly all around very slender twigs. Bark of mature trunks is relatively smooth with faint ridges. Acorns are small (1/2” long) about ¼ enclosed by cup.