OxydÉndrum arbÒreum (LinnÆus) DeCandolle. Sour Wood. Sorrel Tree. Plate 122. Small trees with a gray and deeply fissured bark, much resembling that of a young sweet gum tree; twigs and branchlets greenish and smooth; leaves alternate, on petioles about a cm. long, oblong-oval, generally 10-15 cm. long, narrowed at the base, acute or acuminate at the apex, margins entire toward the base or sometimes all over, usually about three-fourths is irregularly serrate with very short incurved teeth, glabrous above and beneath except a puberulence on the midrib and sometimes on the petiole to which an occasional prickle is added beneath; flowers appear in June when the leaves are full grown, in large panicles at the end of the year's growth, white, the whole inflorescence covered with a short gray pubescence; fruit a capsule about 0.5 cm. long on an erect and recurved pedicel of about the same length, maturing in autumn.

Plate 122

Distribution.—A tree of the elevated regions of the area from southeastern Pennsylvania to Florida and west to southern Indiana and south to Louisiana. In Indiana it is definitely known to occur only in Perry County at the base of a beech spur of the Van Buren Ridge about 7 miles southeast of Cannelton. Here it is a common tree over an area of an acre or two. The largest tree measured was about 1.5 dm. in diameter and 12 meters high. Here it is associated with beech, sugar maple, dogwood, sassafras, etc. When coppiced it grows long slender shoots which the boys of the pioneers used for arrows. A pioneer who lived near this colony of trees is the author of this use of the wood and he called the tree "arrow wood."