This lightest of all native woods in the United States grows in river swamps near the Gulf, about the mouth of the Brazos River. It is a small tree reaching a height of 20 feet, or a shrub, depending upon the location and natural conditions. The base is usually swollen. The straight, gradually tapering trunk is crowned with a loose, open-topped head. The young branchlets are coated with hairs which later drop, leaving a smooth, dark, red-brown stem. [Illustration: CORKWOOD (Leaf, one-half natural size; fruit and winter twig, natural size)] The simple, alternate LEAVES are from 4 to 6 inches long and about 2 inches wide, borne on petioles 1 or 2 inches long. The leaves are shiny above. The FLOWERS are in catkins of two kinds or sexes, the male about 1½ inches long, the female about ¾ inch long. Both kinds are borne on the same tree and appear about the first of March. The FRUIT is solitary or in clusters of 2 to 4, each about ½ to ¾ inch long, and ripens when the leaves are about one-half grown. The WOOD is soft, exceedingly light, generally uniform in texture and of a pale yellow color. It is used as a substitute for cork for floats on fishing nets. EASTERN COTTONWOOD Populus deltoides (Bartr.) This cottonwood is found along streams throughout the state. The tree is easily propagated by cutting and grows rapidly, hence it has been widely planted to get shade quickly. The tree is often unsatisfactory for shade because it begins to shed its leaves by midsummer. The cotton-bearing seeds from the pistillate tree are often a nuisance. The soft wood is easily broken by winds; and the rank growth of the roots often results in stopping drain pipes and cracking and lifting sidewalks. [Illustration: EASTERN COTTONWOOD (Leaf, one-half natural size; twig, one-third natural size)] The LEAVES are simple, alternate, broadly ovate or triangular, pointed, square at the base, and coarsely toothed on the edges, 3 to 5 inches across each way, covered with soft white hairs on the under side, supported by flattened slender petioles, 2 to 3 inches long. The winter buds are covered with chestnut-brown, resinous scales. The male and female FLOWERS are in catkins on separate trees and appear before the leaves. The FRUIT, a capsule, contains a number of seed with white silky hairs which permit the winds to carry the seed for long distances. The WOOD is soft, light-weight, warps easily upon drying, but is used for many purposes, sometimes as a substitute for yellow poplar and linden. Three other species of Southern cottonwood occur in western Texas. One species, P. sargentii Dode, which has long pointed leaves, is found in the Panhandle. BLACK WILLOW Salix nigra Marsh.