But we are forgetting our winter pictures in black and white.' There are other trees with white, or silvery gray bark as well as the birches. Some willows and poplars, the silver maple and the sycamore, a kind of maple or plane tree, have them. And one birch has a yellow bark. You can always tell the birches in winter by the short, brown or dark gray cross-markings on the bark, and by the slender branches and twigs. The willows have many small, drooping twigs but large branches. They often have long, horizontal roots that push the earth up in ridges, and a little forest of switch-like shoots around their feet. The poplars are much like the willows, but their branches are more erect, often growing in so close to the shaft-like trunk as to make these the slenderest trees, except the pines. Switch-like shoots grow about the poplars, and even on the trunks.

In the winter the bark of orchard fruit trees are warm reds and browns and purplish grays, very bright and clean, like wild rose canes. The trunk of an old apple tree may be gray and scaly, but the higher branches and twigs are bright. It has a low, rounded head. Its stout branches spring from a short trunk, making that comfortable "crotch" where you like to sit with a story book in the summer. The crabapple is small, thorny, flat-topped, a twisted witch of a tree. The pear is tall, slim, with a few thick limbs growing upward and close together. The cherry is wine-red. Its outer bark easily peels in circular bands.

The black walnut tree has a towering trunk that branches high in a beautiful crown. Its bark is as black as the oak and elm, and sharply ridged like the shell of its nut. The butternut or white walnut has a grayish bark and high, horizontal branches. The hickory is a tall, spreading tree with a gray bark that breaks away in long strips. For this reason it is often called the shag bark. The twigs are a warm, yellowish brown, with big varnished leaf buds.

The beech tree has low-hung, wide, spreading branches. Its trunk is a smooth bluish-gray column. Nothing that grows under the beech gets enough sunlight, so the ground is often quite bare. The beech, too, like many heavy trees, braces itself with horizontal roots. It is the best umbrella in the world, in a storm, and it is thought to be the safest shelter, for it is seldom or never struck by lightning.

Bare maples are always graceful. The rock maple is a sturdy, compact tree, with its smooth trunk and rounded head. The red maple has a free, bold way of branching like its five-notched leaf.

Winter is the time of the year for finding bird's nests, for the owners no longer need them. The oriole often hangs its purse of a nest, seventy-five feet in the air, from the limb of an elm. Robins and blue birds are fond of apple trees and maples. Little wood owls like the hollows of oaks. The crow picks out a lofty perch in a cotton-wood or pine tree to survey this interesting world. You can find holes the woodpeckers have drilled to drag out grubs, and cocoons tucked away in the ridges of the bark. They hold the baby butterflies waiting for spring. You can tell, too, if a tree is injured or dying. Fungi, or toad stool growths of white or orange fluted ridges, creeping thread moulds, and dry rot around hollows, mean trouble, and decay.

Sometimes, when the Indian boy lay in his wigwam, on a still, cold, winter night, he heard the trees crack. He could not have known what had happened. But now, when sound trees are cut up for lumber, they are often found cracked, across the middle or around a growth ring. The frost does not harm the smallest leaf-bud baby in its cradle, but it often grips and breaks the hearts of big trees.