The snow is still trickling away in little icy streams when the first willow pussies come out for an airing. You will not find them on the big willow trees, but on bundles of knobby switches of willow shrubs that grow with their little webby root feet in the water. The bark is a brownish-green satin, with gummy, scale-covered buds set at regular spaces along the slender, leafless stems.

These scales open, and furry gray noses poke out to take note of the weather. It the sun is shining, the pussies slip right out and sit, as if with toes and tails under them, like so many maltese kittens. You like to rub the silken pussies on your cheek, and you almost expect to hear them purr. But in a few days they swell and stretch and bristle, like kittens with their backs up about something, until every gray hair shows a grain of yellow pollen under it. Shake a twig and see the gold dust fly!

The big willow trees know better than to bloom so early, when Jack Frost nips foolish pussies. When the April sun is quite warm, the black willow takes the brown water-proof caps from its flower buds, and pushes out some catkin tails as scaly as pine cones. Each row of scales is dropped over the next lower one as neatly as the shingles on a church spire. They have no fur, for nobody needs fur in April. Under the scales are seed bottles with eggs in them, but no yellow pollen to feed them. Somewhere nearby, there is sure to be another black willow tree with no eggs, but with pollen catkins as yellow as gold. The bees visit both trees for honey, and so carry pollen to the eggs. The yellow tassels fall very soon, but the scaly ones stay on the trees awhile. By and by the seed babies under the scales get so big and downy that they tumble out of the nests and fly away.

All the catkin bearing trees—the willows, alders, birches and poplars, make these feathered seeds. In April and May, the woods are full of flying white flakes. One poplar is called the cottonwood because of the snow storm of downy seeds it sets loose. The alders are mostly shrubs, growing with the willows along the waterways. Their scaly, worm-like catkins, that you can see in winter, swell into long feathery tassels of purple and gold. On the same bushes are little erect cone-catkins that bear the seeds. The birches like drier soil. You know these white-barked wood fairies, don't you? The birches are shy, and so are their blossoms. You have to lift the thin scales of their catkins to find the thinner scales under them, and the hidden pollen. The tassel grows feathery, and the downy wood sprites of seeds seem to ripen and vanish in a day. The birds use the cottonwood and willow seeds to line their nests with down.

A great many trees flower in April, when the wild flowers in the ground are just poking little green cones through the warm blanket of last year's leaves. The pollen-making blossoms of the elms are little chimes of bells, yellowish or reddish green and, in some kinds, greenish purple. They have so many sturdy little yellow-tipped clappers that you almost expect to hear them ring. In the elm, as in nearly all forest trees, it takes two kinds of flowers, working together, to make seeds. So some of the blossoms of the elms have no clappers, but hairy arms that reach for pollen food. The wind brings it from other trees.

The elm seed is a round, notched and fringed and double-walled green scale, with the seed between two layers, just like the powder in a toy pistol cap. The seed hang in bunches, by inch-long hairs, until the wind tears them loose and scatters them. At the same time in May, the red maple drops its two-winged seeds. They look very much like the thumb screws that you use to tighten bolts, only, of course, they are thin and green.

Oak trees also have two kinds of flowers. One kind is a dwarf catkin or cone, with several double pockets full of gold-dust. The egg flower is a tiny pink knob. It sits away out on the end of the twig in a scaly cup, often snuggled up to a sister or two, like a little bump on a log. Its pink mouth is as wide open as a baby robin's when crying for worms. It wants that pollen! You see, it is a baby acorn. When it gets the pollen it swallows the food, shuts its mouth tight, turns green, and just sits there and grows all summer.