344 
DECIDUOUS TREES. 
broken into a great number of small masses, strongly defined 
against each other ; that is to say, the lights being very bright and 
warm, and the shadows quite decided, and yet softly shaded into 
each other. The disposition of the shadows is rather lateral, but 
not in strata, as on the beech. The head of the tree is remarkable 
for its suiijiy expression ; the parts of the foliage which reflect the 
light being in excess of the parts in shadow. But it lacks for this 
reason the grander, because broader and bolder shadows that give 
superior dignity and variety of expression to the oak, the chestnut, 
and the hickory. The branches are very numerous, and radiate 
with tolerably equal divergence at an angle of about forty-five de- 
grees from the trunk. The bark is light-colored, and the tree has 
a cheerful tone when leafless. 
In streets they should rarely be planted nearer than twenty-five 
feet from each other, and thirty feet apart is better. 
The average yearly growth of the sugar maple is about fifteen 
inches. It is most at home in a gravelly soil, and where such soils 
are rich and well drained it grows rapidly, while in stiff clay, or 
ill-drained sandy ground, the growth is slow. In ten years after 
planting it usually grows to about twenty or twenty-five feet in 
height, and fifteen feet across its top. Height at maturity from 
fifty to seventy feet. 
The Black or Rock Maple, Acer nigrum^ is a variety of 
the sugar maple, with darker and less deeply-lobed leaves, more 
globular form, and lesser growth. 
The White or Silver-leaved Maple. Acer eriocarpum . — 
This native maple, so common on the banks of western streams, 
has become, perhaps, too great a favorite for street planting. Its 
growth is very rapid, being nearly double that of the sugar maple. 
Its form is much looser and more spreading, becoming at maturity 
an irregularly square-headed tree; the foliage is smaller, less 
dense, of a lighter green on the upper surface, and the under sur- 
face a downy white, which peculiarity gives the tree its name. The 
stems of the leaves being small and slender, the foliage, as the 
long branches sway in the wind, is ruffled so as to contrast the 
