AMERICAN FOREST TREES 447 



It may be expected that box elder will exist in the United States as 

 long as any other forest tree remains. It is willing to be crowded off 

 good land into low places, which are almost swamps, and there it grows 

 free from disturbance; but if given the opportunity it will appropriate 

 the most fertile soil within reach of it; and by scattering seeds during 

 four or five months of the year, it manages to do much effective planting. 



CALIFORNIA Box ELDER (Acer negundo calif ornicum) is a variety of box elder. 

 and not a separate species. As the name implies, it is a California tree, and it occurs 

 in the valleys and among the Coast Range mountains from the lower Sacramento 

 valley to the western slopes of the San Bernardino mountains. The tree is from 

 twenty to fifty feet high and from ten to thirty inches in diameter. The leaves and 

 young twigs are hairy, in that respect differing from the eastern box elder. The seeds 

 are scattered during winter. The wood is very pale lemon-yellow or creamy-white, 

 the heart and sapwood hardly distinguishable. The wood is soft and brittle, but is 

 suited to the same purposes as the eastern box elder. No reports of its uses appear to 

 have been made. It is found on the borders of streams and in the bottoms of 

 moist canyons. It is believed to be a short-lived tree. 



STRIPED MAPLE (Acer pennsylvanicum) is usually thirty or forty feet high, and 

 eight or ten inches in diameter. Its range extends from Quebec to northern Georgia, 

 westward to Minnesota, and is of largest size on the slopes of Big Smoky mountains 

 of Tennessee, and the Blue Ridge in North and South Carolina. It grows best in 

 shade, but maintains itself in open ground ; is generally shrubby in the northern part 

 of its range. The name refers to the bark. The stripes are longitudinal and are 

 caused by the parting of the outer bark and the exposure to view of the lighter colored 

 inner layers. The bark of small trees is greenish, but later in life the color is darker, 

 and the stripes largely disappear. Among its names are moosewood, so called be- 

 cause it is good browse for moose and other deer; goosefoot maple, a reference to the 

 form of the leaf; whistlewood, an allusion to the ease with which the bark slips from 

 young branches in spring when boys with jack-knives are on the search for whistle 

 material. The names mountain alder and striped dogwood are based on misunder- 

 standing of the tree's family relations. 



The young leaves are rose colored when they unfold, and when full grown are 

 six inches wide. The wood is light and soft, and light brown in color, the thick sap- 

 wood lighter. The wood is liable to contain small brown pith flecks, which in longi- 

 tudinal sections appear as brown streaks an inch or less in length and as thick as a pin, 

 and in cross section they are brown dots. They are not natural to the wood but are 

 caused by the larvae of certain moths which burrow into the cambium layer, or soft 

 inner bark, and excavate narrow galleries up and down the trunk. The galleries 

 afterwards fill with dark material. The insects sometimes attack other maples, the 

 birches, service, and other trees. The wood of striped maple is little used, because of 

 the small size of the trees. The species is planted for ornament in this country and 

 Europe. 



BLACK MAPLE (Acer nigrum) has been by some considered a variety of sugar or 

 hard maple, and by others a separate species. It is as large as the sugar maple and its 

 range is much the same, but it is more abundant in the western part of its range than 

 in the East. The name refers to the color of the bark of old trunks. If the name had 

 considered the bark of young twigs it. would have been yellow or orange maple, 

 because the twigs are of that color. In summer the peculiar drooping posture of the 

 leaves calls attention to this tree. However, the bark, twigs, and leaves combined 



