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DescriptionThis is a submerged or floating aquatic plant (about ½-12' long) that branches at right angles (90°). The jointed stems are pale green to reddish purple, glabrous, and fragile, often dividing into smaller segments. Along these stems, there are whorls of 5-14 divided leaves that curve upward; these leaves are 1-4 cm. long. The leaves are more crowded toward the growing tips of stems than elsewhere; they are medium to dark green and glabrous. Both stems and leaves have a tendency to be somewhat stiff and brittle, especially when they are coated with lime in calcareous water. Each leaf divides dichotomously into 2-4 segments (rarely more); these segments are narrowly linear (up to 0.5 mm. across) and flattened. Each leaf segment is conspicuously toothed along one side, while it is smooth (entire) on the other side. Coontail is monoecious, forming male (staminate) and female (pistillate) flowers on the same plant. Both types of flowers are produced in the axils of the leaves and they are sessile. Female flowers occur individually, while male flowers occur either individually or in pairs. Both types of flowers are very small in size (about 2 mm. in length), and they have involucres consisting of 8-14 floral bracts that surround the reproductive organs. These bracts are translucent and broadly oblong; their tips are truncate and fringed. There are neither sepals nor petals. Each female flower has a single pistil with a long slender style, while each male flower has 8-14 anthers that are sessile or nearly so (very short or absent filaments). The blooming period occurs intermittently during the summer and early autumn. Cross-pollination is accomplished through water currents. However, only a few flowers, if any, are produced by individual plants. The female flowers are replaced by 3-spined achenes. The body of each mature achene is 4-6 mm. long, ovoid in shape, slightly flattened, and wingless along its sides. Each achene has 2 basal spines and a single spine at its apex; these spines are 0.5-12.0 mm. in length and they are either straight or curved. Coontail has no real root system, although it is able to anchor itself in mud or sand through either lodged stems or the development of modified leaves. By late autumn, winter turions (tight buds of leaves) develop at the tips of stems that sink to the bottom of a body of water, where they remain until spring of the following year. Growth and development begin again with the return of warmer weather. In addition to its achenes and winter turions, Coontail reproduces vegetatively whenever its stems divide into smaller segments.