The _quaking aspen_ (_Populus tremuloides_), the _large-toothed aspen_ (_Populus grandidentata_) and the _balsam poplar_ or _balm of Gilead_ (_Populus balsamifera_) are other common members of the poplar group. The quaking aspen may be told by its reddish-brown twigs, narrow sharp-pointed buds, and by its small finely toothed leaves. The large-toothed aspen has thicker and rather downy buds and broader and more widely toothed leaves. The balsam poplar has a large bud thickly covered with a sticky, pungent, gelatinous substance. GINGKO OR MAIDENHAIR TREE (_Gingko biloba_) [Illustration: FIG. 44.--Gingko Trees.] Distinguishing characters: The *peculiar branches* of this tree *emerge upward* from a straight tapering trunk *at an angle of about 45°* and give to the whole tree a striking, Oriental appearance, which is quite different from that of any other tree, Fig. 44. Leaf: Like that of a leaflet of maidenhair fern, Fig. 45. Range: A native of northern China and introduced into eastern North America. Soil and location: The gingko will grow in poor soils. Enemies: Practically free from insects and disease. [Illustration: FIG. 45.--Leaves of the Gingko Tree.] Value for planting: It makes a valuable tree for the street where heavy shade is not the object and forms an excellent wide-spreading specimen tree on the lawn. Other characters: The _fruit_ consists of a stone covered by sweet, ill-smelling flesh. The tree is dioecious, there being separate male and female trees. The male tree is preferable for planting in order to avoid the disagreeable odor of the fruit which appears on the female trees when about thirty years old. The male tree has a narrower crown than the female tree. The buds (Fig. 46) are very odd and are conspicuous on the tree throughout the winter. The leaves of the gingko shed in the winter. In this respect the tree is like the larch and the bald cypress. [Illustration: FIG. 46.--Bud of the Gingko Tree.] The gingko belongs to the yew family, which is akin to the pine family. It is therefore a very old tree, the remains of the forests of the ancient world. The gingko in its early life is tall and slender with its few branches close to the stem. But after a time the branches loosen up and form a wide-spreading crown. In the Orient it attains enormous proportions and in this country it also grows to a fairly large size when planted on the open lawn or in groups far apart from other trees so that it can have plenty of room to spread. It then produces a picturesque effect of unusual interest. WEEPING WILLOW (_Salix babylonica_) Distinguishing characters: All the willows have a single cap-like scale to the bud, and this species has an unusually *drooping mass of slender branchlets* which characterizes the tree from all others, Fig. 47. [Illustration: FIG. 47.--Weeping Willow.]