246 



associated with cypress, swell-butt ash, buttonbush, sweet gum, etc. 

 All of the trees of this locality have 5-lobed leaves. 



A specimen collected in the "bottoms" about two miles east of 

 Huntingburg in Dubois County has 3 -lobed leaves which are tomentose 

 beneath at fruiting time and has fruit intermediate in size between the 

 type and variety Drummondii which I doubtfully refer to variety 

 tridens Wood. 



4. Acer nigrum F. A. Michaux. BLACK MAPLE. BLACK SUGAR. 

 Plate 114. Medium to large sized trees with dark furrowed bark on old 

 trees; leaves a little wider than long, 6-15 cm. long, on petioles usually 

 3-15 cm. long which are more or less swollen at the base and by maturity 

 develop a scale like appendage on each side of the petiole at the base- 

 especially on each of the terminal pair of leaves, sometimes with foliar 

 stipules which are 2-3 cm. long on stalks of equal length, leaves with 

 three main lobes, the two lower lobes generally have a small lobe at their 

 base, margins of lobes entire and undulating, sinuses between main 

 lobes generally rounded at the base, wide and shallow, base with a 

 narrow sinus, the lower lobes often overlapping, rarely somewhat den- 

 tate, dark green above and a paler yellow green below, hairy on both 

 surfaces when young, becoming at maturity glabrous above and re- 

 maining more or less pubescent beneath; flowers appear in May when 

 the leaves are about half grown on long hairy pedicels, the staminate 

 and pistillate in separate clusters on the same or different trees; fruit 

 matures in autumn, the samaras about 3 cm. long. 



Distribution. Quebec to Georgia, west to South Dakota and south 

 to Louisiana. Found in all parts of Indiana and invariably associated 

 with sugar maple, and often with beech in addition. Frequently almost 

 pure stands of sugar maple may be found with the black maple absent. 

 Where found it is usually a frequent to common tree, and when it occurs 

 on a wooded slope it is more frequent near the base and appears to be 

 able to advance farther into moist situations than its congener. 



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 



