S Samara—An indehiscent winged fruit such as that of maple. Sapwood—The recently formed, usually light colored wood, lying outside of the heartwood. Scabrous—Rough, with stiff, bristly hairs. Scales—The small, modified leaves which protect the growing-point of a bud or the part of a cone which bears the seeds. The small flakes into which the other bark of a tree divides. Scurfy—Covered with small bran-like scales. Serrate—Having sharp teeth on margin. Sessile—Seated; without a stalk. Sheath—A tubular envelope or covering such as surround the base of pine-needles. Silky—Covered with long, soft, straight, fine hairs. Simple—Consisting of one part, not compound. Sinus—The cleft or opening between two lobes. Sinuate—Wavy. Softwood—A general term given conifers, the wood of which may or may not be of low density. Stamen—Male organ of flower. Consists of a pollen-bearing anther on a filament. Stipule—A leaf-appendage at the base of the leaf-stalk. Stipule-scar—The scar left by the fall of the stipule. Stolon—A runner or basal branch that may root. Striate—Marked with fine elongated ridges or lines. Striations—Long narrow lines or ridges. Strobile—A fruit marked by overlapping scales as in the pine, birches, etc. Sucker—A shoot arising from an underground bud. Superposed—Said of buds when they are arranged one above the other. Symmetrical—Regular as to the number of parts. Having the same number of parts in each circle. T Terminal—Located at the outer end. Thorn—A stiff, woody, sharp-pointed projection as found on locust; a spine. Tolerant—Applied to trees which endure certain factors, particularly shade. Tomentose—Densely pubescent; hairy. Covered with matted-hairs. Tomentum—A dense layer of woolly hairs. Truncate—Ending abruptly, as if cut off at the end. Tufted—Growing in clusters. U Unisexual—Consisting of one sex only, either staminate or pistillate. V Valvate—Said of buds in which the scales merely meet without overlapping. Fruit opening by valves. Veins—Threads of fibro-vascular tissue in leaves or other organs. W Whorl—A group of three or more similar organs, as leaves or buds, arranged about the same place of attachment. Whorled—Borne in a whorl. Index