There are two kinds of _leaves_, often both kinds being found on the same tree. The commoner kind is dark green, minute and scale-like, clasping the stem in four ranks, so that the stems appear square. The other kind, often appearing on young growth or vigorous shoots, is awl-shaped, quite sharp-pointed, spreading and whitened beneath. The two kinds of _flowers_, appearing in February or March, are at the ends of the twigs on separate trees. The staminate trees assume a golden color from the small catkins, which, when shaken, shed clouds of yellow pollen. The _fruit_, ripening the first season, is pale blue with a white bloom, 1/4 inch in diameter, berry-like with sweet flesh. It is a favorite winter food for birds. The _bark_ is very thin, reddish-brown, peeling off in long, shred-like strips. The tree is extremely irregular in its growth, so that the trunk is usually more or less grooved. The _heartwood_ is distinctly red, and the sapwood white, this color combination making very striking effects when finished for cedar chests, closets, and interior woodwork. The wood is aromatic, soft, strong, and of even texture, and these qualities make it most desirable for lead pencils. It is very durable in contact with the soil, and on that account is in great demand for posts, poles and rustic work. The arbor vitae or northern white cedar, _Thuja occidentalis_ L., is found occasionally on the bluffs overlooking Lake Michigan, on the cliffs of Starved Rock, in Elgin City Park, and in bogs in Lake County. The leaves are aromatic, scale-like, 1/8 inch long, arranged to give small flat branches. The fruit is a cone 1/2 inch long. The wood is light, soft, durable, fragrant, and pale brown. +QUAKING ASPEN+ _Populus tremuloides_ Michx. THIS is one of the most widely distributed trees in North America. Its range goes from Labrador to British Columbia and from New England and New York far south in the Rocky Mountains to Arizona. In Illinois it is common in the north, but of infrequent occurrence in the south. [Illustration: ASPEN Three-fourths natural size.] The aspen is a small tree, reaching heights of 40 to 60 feet and diameters of 10 to 20 inches. The young branches are reddish-brown soon turning gray. The _winter buds_ are about 1/4 inch long, pointed and shining. The _bark_ is thin, smooth, light gray tinged with green. The _leaves_ are on slender flat petioles, arranged alternately on the twigs, and broadly oval, short pointed and shallowly toothed. They are green, shiny above and dull below, ranging from 2 to 4 inches long and about the same in breadth. The _flowers_ are in catkins and appear before the leaves begin to expand. The two kinds are borne on separate trees, the staminate catkins are about 2 inches long, but the seed-producing flowers form a long slender cluster 4 inches in length. The _fruit_ is a conical capsule filled with tiny cottony seeds which ripen in late spring before the leaves are fully expanded.