=Remarks.=--This tree cannot be distinguished from the sugar maple by its form, but at short range can be separated from it by its richer green foliage and by the drooping habit of the lower lobes of the leaves. It is commonly separated from the sugar maple by the darker color and by the narrower and shallower furrows of the bark, but these characters will not always separate the two species. Hence, when buying black maple trees from a nurseryman you may receive the sugar maple. Those who distinguish the two species agree that the black maple is the more desirable tree for shade tree planting. The black and sugar maple are the two most desirable trees for shade tree planting in Indiana. They are long lived, have a very desirable form, beautiful foliage, a long leaf period, and are quite free from disease and insect injury. [Illustration: Plate 114. ACER NIGRUM. F. A. Michaux. Black Maple. (× 1/2.)] =5. Acer sáccharum= Marshall. Sugar Maple. Sugar Tree. Hard Maple. Rock Maple. Plate 115. Usually large, tall trees. The bark of small trees is smooth or rough, becoming fissured on old trees, tight or on very old trees sometimes the ridges loosen on one edge and turn outward. The leaves are extremely variable on different trees, and frequently show a wide variation on the same tree, as to form and in the presence or absence of hairs on the petioles and on the under surface of the leaves. In our area all of the forms which have the majority of the leaves longer than wide or about as wide as long, may be considered as falling within the type. The average sized leaves are 6-12 cm. long, 3-5 lobed, more or less cordate at the base, generally with a broad sinus, sometimes truncate or slightly wedge-shape, sinuses generally wide-angled and rounded at the base, sometimes acute, hairy beneath when young, becoming smooth at maturity except for a few hairs along the veins or in the main axils of the veins, or sometimes remaining more or less pubescent over the whole under surface, more or less glaucous beneath; flowers appear in April or May, on hairy pedicels 3-7 cm. long, the staminate and pistillate in clusters on the same or different trees; fruit ripening in autumn, samaras glabrous and usually 2-4 cm. long. =Distribution.=--Newfoundland to Georgia, west to Manitoba and south to Texas. A frequent to a very common tree in all parts of Indiana. It is confined to rich uplands, or along streams in well drained alluvial soil. Throughout our area it is constantly associated with the beech. It is absent in the "flats" of the southeastern part of the State, and on the crest of the ridges of the "knob" area of Indiana, but it is a frequent or common tree on the lower slopes of the spurs of the "knobs."