The LEAVES are simple, alternate on the stem, 4 to 6 inches in length, sharp-pointed, their bases unsymmetrical, doubly toothed on the edges, thick, dark green, and very rough above, pubescent below. [Illustration: SLIPPERY ELM (Leaf and fruit, one-third natural size; twig, one-half natural size)] The FLOWERS appear in early spring and are nearly sessile. The FRUIT, a samara, ¾ inch long and ½ inch in diameter, consists of a seed surrounded by a thin, broad, greenish wing. The fruit ripens when the leaves are about half grown. The margin of the fruit is not ciliate. The WOOD is close-grained, tough, strong, heavy, hard, and moderately durable in contact with the soil. Slippery elm and American elm are sold commercially as “soft elm,” and have similar uses. PLANER TREE (Water Elm) Planera aquatica (Walt.) Gmel. Planer tree or water elm is found on low wet lands along the streams of the eastern part of the state as far west as Brazos and Matagorda Counties. It forms a small spreading tree with a low broad head 30 to 40 feet in height and with a maximum trunk diameter of 20 inches. [Illustration: PLANER TREE (Illustrations, nearly natural size)] The BARK is light brown or gray, about ¼ inch thick, and separates into large scales. The LEAVES resemble those of the small-leaved elms. They are 2 to 2½ inches long, ¾ to 1 inch wide on a short petiole, dark dull green above and paler on the lower surface, and have yellowish veins. The FLOWERS appear with the leaves in March or early April. The small flowers are sometimes perfect; occasionally the male and female flowers are borne separately on the same tree. The FRUIT is a peculiar, rounded, shaggy-appearing structure, about ⅜ inch long. It consists of a nut-like center covered with soft and irregular wing-like outgrowths which extend out on all sides from the center. The WOOD is light brown, coarse-grained and soft, very light in weight, and has a broad zone of nearly white sapwood. The wood has little economic value. HACKBERRY Celtis occidentalis L. Hackberry is found over eastern Texas on various types of soil. It is usually a medium-sized to large tree, becoming 60 to 100 feet or more high and 10 to 20 inches in diameter. Its limbs are often crooked and angular and bear a head made of slender, pendant branches or short, bristly, stubby twigs. In the open, the crown is generally symmetrical. It makes an excellent shade tree. The BARK is brownish-gray, one inch or more thick, and generally very rough with many scale-like or warty projections of dead bark. [Illustration: HACKBERRY (Leaf and fruit, two-thirds natural size; twig, one-half natural size)]