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I 
BROOKLYN BOTANIC GARDEN 
LEAFLETS 
THE BROOKLYN INSTITUTE OF ARTS AND SCIENCES 
Series IV Brooklyn, N. Y., April 19, 1916. No. 3 
TEN COMMON TREES OF BROOKLYN 
In a former Leaflet (Ser. I, No. 7) coniferous trees have 
been described; ten other genera of trees commonly seen in 
Brooklyn are here taken up. 
Maple .— The maples are readily distinguished as a group by 
their opposite buds and their usually palmately veined simple 
leaves. The bark is generally smooth, at least on the branches. 
The flowers soon develop into a double-winged fruit. The small 
red flowers of the silver maple and the somewhat more conspicu- 
ous ones of the red maple come out before the leaves. In the 
sugar maple they come out about the same time as the leaves. 
Two European species often planted here — the Sycamore maple 
and the Norway maple — have more showy flowers. The Norway 
maple is very common as a street tree, and is noteworthy in that 
it has a milky sap. The box-elder, or ash-leaved maple, has 
bright green twigs and pinnately compound leaves. 
Elm .— The elms have simple, pinnately veined leaves, with 
serrate margins. The bark is rough. The flowers are usually 
perfect — that is, having both stamens and pistils. They appear 
before the leaves, and develop into a flat-winged fruit, which falls 
to the ground early in the season. The American or white elm is 
one of the tallest of our trees. Its gracefully dividing trunk and 
branches give it a distinct appearance. The English elm has a 
form more like an oak. The slippery elm is a smaller tree; it has 
rather larger leaves with a rough surface. 
Plane Tree . — The plane trees, commonly called sycamore or 
button ball, are very distinct by their peculiar flaky bark and 
globular, suspended fruit, which remains on the tree through the 
winter. The leaves resemble maple leaves somewhat, but are 
alternate; the base of the peticles is hollow and encloses next 
