Part 10

Among the fine, feathery leaves that are so beautiful and light that they give great beauty to the tree tops are those of the honey locust. These leaves are of the feather type, the slender stems, with double rows of tiny leaflets. Very often we find among the single feather forms, leaves of greater size, which have branched stems. This branching multiplies the number of leaflets, and gives us, on the same trees, what the botanists call _once compound_, and _twice compound_ leaves. The simple feather and the branched feather forms add greatly to the beauty and luxuriance of the foliage of the honey locust.

The common black locust of the roadside has single leaf stems with oblong leaflets set in opposite rows upon it. Ash trees have the same feather type of leaves, the leaflets usually pointed and oval, and always an odd one at the tip. They are all larger than leaves of the locusts.

In the maple family there is a broad, simple blade, about as wide as it is long. It is a family trait to have three main veins running out from the end of the leaf stem, into the blade. Each of these veins has side branches, and they are connected with a network of smaller veins. Between the tips of these three main veins the leaf is usually notched, so as to divide it into thirds. In the red maple these notches are shallow V’s cut out, leaving triangular points. In the silver maple the leaves are cut by deeper clefts, which reach more than half-way to the leaf stalk. The three lobes are cut with jagged points into an uneven margin. The sugar maple has its three lobes separated by wide, deep clefts, and its margins are irregularly wavy. The box elder, which is a maple, is cleft so deeply that the blade is split into three distinct leaflets, each with its own short stem. This makes a compound leaf of it. It is the only maple with a leaf of more than one blade.

The tree which shows the greatest difference in the form of its leaves is the sassafras, whose oval leaves grow on the same stem with mittens and double mittens—a mitten pattern with a thumb on each side. The hawthorns have small oval leaves with variously cleft borders. There are over a hundred kinds of hawthorns in our woods, and each kind has a leaf different from all the rest; yet a single tree will often show leaves that differ so much from the others in form that we might easily suspect, if some one brought them to us, that each grew on a different tree from all the rest.

Many oak trees have the same habit of leaf variation, so that even a forester has to examine many leaves with care, and with them the buds and the acorns, to make sure that he has called the oak by its right name.

The behaviour of the leaves of a tree depends largely on the length and flexibility of their stems. If they are long, and slender, and supple, the tree-top is in a continual flutter when the wind blows. If they are thick and stiff, they do not catch the breeze as readily, and their blades lie comparatively still when other trees near by may be twinkling and trembling. Leaves with deeply cut borders, like some oaks and maples, flutter much more than leaves like the basswood, whose borders are unbroken. Oak leaves that are deeply cut will rarely lie down flat. The curving bays in its borders cause the leaf to curl, so that no matter what face is presented, the wind gets under and strikes some surface, and sets the leaf to dancing.

The flat leaf stems of the trembling aspen, one of the poplar family, are very flexible, and they are flattened at right angles to the blades of the leaves. When a breeze comes by, it may strike the edge of the leaf, but if so, it catches the flat leaf stem broadside. If it comes from any other direction the leaf trembles, because one of the blades is sure to receive the force of the wind. So the tree top is in one constant tremor, even when the breeze is scarcely sufficient to disturb broad-leaved trees which are near neighbours of the aspens.

Whatever the form and size and shape of its leaf, the tree depends upon its foliage mass for all the life it enjoys, and for all the growth it makes. The soil and the air feed the tree. The leaves and the sun do the work of digesting the food. In the porous wood and bark are the channels through which sap mounts upward to the leaves, and another set of channels which carry the prepared food back, leaving it wherever needed, along the way from tip of twig to tip of root. Whatever is not needed is stored away, to be dissolved as needed and carried to the points where the need is. In spring it is the growing buds that chiefly need this stored food. Its presence explains the miracle of the bursting of blossoms and leaves when spring comes.

One by one the trees of your own yard may be learned by name this summer. The leaves are your sure guide. Trees stay where they are. Once we recognise their leaves and call them by name, we may depend upon finding them still standing the next day we pass them, and their leaves are still held out as the sign of recognition. Every time we pass yonder red maple let us glance at its three-pointed leaf, and fix its shape indelibly in the mind. When we have done this a dozen times, I am sure that we shall be able to pick out all the red maples in town; and if we journey far from home we may find and recognise the same kind of trees by the same sign. More and more as we grow older, we find out that half the pleasure of travelling is the occasional meeting with old friends, be they people or trees.

TREE STUDIES IN THE SUMMER

TREES WITH THE LARGEST FLOWERS

If we set out to find the trees that have the largest flowers, meaning to count only trees that grow wild in our woods, it will save time to go straight south into North Carolina, and climb the foot hills of the Allegheny Mountains. Or it may be that in the fertile valleys that lie between the low ridges we shall first come upon a magnolia, called the large-leaved cucumber tree. Anywhere from North Carolina to Florida, and west to Arkansas, these remarkable trees are likely to be found, in small groups. In cultivation, they are successfully planted as far north as Boston.

Before the tree has attained more than a man’s height it is a wonder, on account of the leaves which measure more than a foot in length, and have their long, green blades lined with white. In June the flowers open—great white bowls, made of waxen petals, in a double row, the inner ones painted purple at their bases, giving the flower a purple centre.

The wind blows the leaves about, and tears them into rags, unless the tree is in a sheltered place. The silvery leaf linings, as white as the blossoms, make it difficult to see that the tree is in bloom, until one is close enough to see the petals. If the leaves were green on both sides the great blossoms, as large as a man’s head, would be seen afar off. The tree would look like a giant rose bush.

From Pennsylvania southward to the Gulf of Mexico, and west to Arkansas and Texas, the evergreen magnolia grows on stream borders, and even on uplands where the soil is not very moist. When this pyramid of shining green leaves lights all its waxen tapers, it is a sight worth a day’s journey to see. Each stiff twig is bent upward, and there a bud appears in spring. A few at a time, the flowers open, and the blooming time lasts till August.

Each blossom is a deep, creamy cup, made of six wax-like petals, surrounded by three white sepals. Inside are many stamens, purple at the base, and a cone of pistils, all grown together.

The leaves are oblong or oval, often eight inches long, thick, deep green, and bright as if polished on the upper surface. The lining is dull green, sometimes covered with rusty down. The paler green and the brighter polish on the young leaves add much beauty to the tree in summer. In winter the leaves get grimy and the tree top is sombre, for most of the foliage has seen much wear and tear.

In autumn the ends of the twigs hold up green cones, made of many furry capsules that end in curved horns. Each capsule splits when ripe, and a scarlet seed, like a berry, hangs out on an elastic thread, and swings lower and lower, until finally it is carried away. Thus the magnolia sows its seeds in winter.

The shining leaves of this magnolia come North at the Christmas season, and are used to decorate homes and churches. Holly, mistletoe, palm leaves, and the beautiful Southern smilax are other Christmas greens now commonly in use. They are all gathered with magnolia and shoots of the long-leaf pine, in the woods down South.

The swamp bay is a magnolia that grows as a shrub to New England, keeping to the swampy lands that skirt the Atlantic coast. Every spring the fragrant, creamy blossoms are to be bought from street Arabs in New York and Philadelphia. A single globular flower is surrounded by a whorl of oval leaves, bright green, but lined with a white, powdery substance that makes them look silver-lined. The flowers are deliciously fragrant, and most beautiful when not spread wide open. The seller often takes the trouble to spring the petals back, to make the blossom seem bigger. The waxy petals turn brown soon after such handling, and all their natural beauty departs.

From Florida westward to Texas this magnolia becomes a slender, tall evergreen tree. The best flowers of this tree are borne on shoots that are produced by pruning back the new growth each year. The largest leaves and flowers are also the handsomest.

The cucumber tree is the magnolia of the North. It is a fine tree in Ontario, Canada, and from this region it spreads south, its range widening like a fan, reaching from Arkansas to the Carolinas, and Mississippi, and Alabama. The tropical appearance of the tree is due to the big, heart-shaped leaves. Their tulip-like flowers are as large as garden tulips, but they make scarcely any show, because they are very much the same in colour as the yellowish-green new leaves that surround them.

The “cucumbers” are the green cones that contain the seeds. They are very lumpy and irregular in form, but when ripe the cells split open and the scarlet seed, let down on an elastic thread from each, looks like any magnolia seed.

Cucumber wood is soft, yellowish-brown, and close-grained. It is not very good lumber, though put to many uses. The tree is worth more alive than dead. It is an admirable shade tree, though not planted as much as it deserves.

The tulip tree is a close relative of the magnolias. It is one of the trees with large flowers, though, like the cucumber tree, the colour of the flowers makes them rather inconspicuous. In June the upturned twigs blossom with yellow tulips. The three sepals flare outward, the petals form the cup. A band of orange decorates the cup, and signals the bees which come for nectar hidden near the bottom of the flower cup, among the bases of the many stamens.

Many people see the gay petals of the tulip tree flowers when they fall on the sidewalk, and some wonder what these bits of colour are. A few will say: “There must be a tulip tree near by,” and look up to find the singular squared-leaf blades that belong to no other tree. There is a whole tree top fluttering with them, and this tremulous motion explains why the tree is often called the tulip poplar. The yellow wood gives the name, yellow poplar. Pulp of this wood is used for the manufacture of the ordinary postal cards. It has many other uses, and is a valuable lumber tree. For shade and ornament it is one of the best trees to plant.

The cones of the tulip tree do not set free their seeds, as those of the magnolias do. Instead of horned capsules, the cone has flat, overlapping blades, like the wing of a maple seed, and the small, closed seed case is the base of the blade. A few of these seeds are fully developed. But when the winter strips the tree of its leaves, the wind shakes the cones, and the loosened scales gradually fall. The wind catches the flat wings, and away they sail. Little tulip trees grow up where good seeds fall in favourable ground.

One day a neighbour told me that there was a tree in blossom on the side of the ravine. This was a strange story, for it was the dead of winter. We went to see this wonderful tree. What do you think it was? A tulip tree, with the seed cones half stripped of their seeds, and shining like yellow flowers on the ends of the twigs. It was not strange at all that a person who did not know the tree, and had never seen its cones in mid-winter, should make this very mistake.

The flowering dogwood invites us every spring to break off branches covered with big, white blossoms, each like a four-pointed star, with a cluster of small white buds in the centre. The trees are small and low-branching, their limbs are flat, and they spread outward and slightly downward. Who can resist cutting a few of the blossoming boughs of this lovely tree! The best part is that the tree suffers not at all if the pruning is done with some care. Take a thought for the tree; cut the branches clean with a knife. Take them off where they are thick, and you will leave the tree better in shape than when you came. Do not strip it of flowers. This will cripple it. A few sprays of dogwood, prettily arranged in a vase, are a delight to the eye. A crowded mass of them is not at all.

The four outer wings of white are not the petals of a dogwood blossom. They are colourless leaves, the full-grown scales of the winter flower buds. The notch at the tip is made by the falling off of the withered tip which in winter protected the flowers. The base grew long and broad and turned gradually white. The bees see these white banners farther, perhaps, than they can catch the faint perfume. Watch the bee as she probes the middle flowers for nectar. See the pollen on her hairy body. From one to another, she is the pollen distributor of these flowers, and she doesn’t know it.

TREES MOST SHOWY IN BLOOM

Sometimes a tree with very small flowers has such a multitude of them that it attracts more attention and admiration when in blossom than the trees with the largest flowers. A magnolia blossom as large as a cabbage head must sacrifice delicacy to size. We must see it at a distance to overlook its coarseness, and to escape its overpowering perfume.

An orchard in early May is transformed into fairyland by the opening of millions of buds. Apple trees have just begun to unfold the new leaves. They are pale green, and coated with white hairs, so that a silvery cloud rests on the tree when the white blossoms, warmed with a tinge of pink, come with a rush that takes one’s breath away.

A single apple blossom has its five flaring petals inside of five green sepals that are the bud’s green overcoat. The stamens are many; the pistils five in the centre of the flower. The plan of the flower is five. The green lump below the blossom is the apple, already forming. Inside it are the five cells of the core, and each has its seeds already forming, if the five pistils have each caught a grain of pollen for each of the embryo seeds its chamber of the core contained.

The delicate colour and rich fragrance of the apple orchard are enchanting. To the honey bees these two signals call to a feast of nectar. All unknown to them, they carry pollen on their furry bodies from flower to flower, and thus enable the pistils to set seed. If the days are damp and there are frequent showers while the apple trees are in bloom, the bees are kept at home, and there will be but a small crop of apples. Fortunately for the bees and for us, the blossoms do not all come out on the same day. The trees and the bees are hopeful till the last moment that the sun will shine, and the nectar be gathered, before the opportunity of the year passes.

Flowers much like apple blossoms in form cover the twigs of hawthorn trees. They are usually in many-flowered clusters, set off by the green leaves. Fragrance, sometimes sickening sweet, draws the bees and other insects to these trees. Nectar drips from the blossoms of some species. The thorny branches spread sidewise, holding the blossoms out in wide platforms. The red fruits, called haws, adorn the trees in late summer.

Plum and cherry trees are laden with white bloom, and heavy with fragrance. Some species haven’t a leaf when they bloom. And these are among the showiest of blossoming trees. In these flowers there are single pistils, and but a single grain of pollen is needed to set seed. The single seed is the pit, or stone, of this family known as the trees with stone fruits.

TREES THAT BLOOM IN MIDSUMMER

In spring the big chestnut tree is late in putting out its leaves. It is May before the bare limbs are clothed with green. This crown is made of long, pointed leaves, each short-stemmed, strongly ribbed, with parallel veins on each side of the midrib, polished and sharp-toothed along its margin. It is a superb dome of unusually handsome leaves.

When the flower procession is long past and the grain fields have turned yellow, and the mower and reaper are humming busily, the chestnut’s crown turns from green to gold, as if to harmonise with the landscape of midsummer. Each twig ends in a feathery yellow plume, which waves in the breezes, and sheds its yellow pollen abroad. The fertile flowers are at the base of the plume. As the yellow pollen flowers fade, the green scaly ones below them are swelling. They are the young chestnuts. The long tongue each held out to catch pollen when it was ready for use. Each flower has three nuts as its full quota to form. Failure to be pollenated may cause one of the three to fail. The husk will then contain two nuts.

In May the yellow locust trees still stand along the roadsides, or herded together along the banks of streams, bare and ugly, while the trees around them are beautifully clothed in their green garments, and adorned with blossoms. The dead pods still cling to the locust’s branches, and not even the buds are in sight to prove the twigs alive.

Suddenly the trees wake, push out their hidden buds into shoots which unfold leaves made of tiny leaflets. The leafy spray is light and graceful, pale green with a silvery sheen at first. Soon the leaves are inundated with a flood of white blossoms, fragrant with their nectar, which hang in clusters from each twig. The bees see the white cloud on the locust tree, and hurry to the feast. Each curious pea-like flower has a honey pot in its horned petal. Throughout the summer the locust trees wave their fern-like leaves, among which the young pods swing, rosy and green, and velvety soft. The two thorns at the base of each leaf are there, but they are not conspicuous, unless you grasp a limb; then they let you know where they are, and what they can do.

On a summer evening we shall see that the locust has closed its leaves, folding the opposite leaflets together, and the whole leaf drooping from its stem. It reminds us of the old-fashioned sensitive plant whose leaves resembled these, folded its leaflets and drooped whenever it was touched. Indeed, the locust tree and these plants are near relatives. The locust leaves are sensitive to the evening air. They close if a rain comes up, but open when the sun comes out again and the sky clears.

Locust trees have an insect enemy which bores into the solid wood, and ruins it for lumber. Even the twigs are swollen and distorted by these insects, which feed upon the rich sap that should go to feed the tree. It is impossible to reach this enemy with poison, so the trees are helpless.

Except for this unfortunate fact, locusts would be a profitable crop to raise for timber. Locust wood is very hard, durable, and strong. It is slow to decay when in water, so it is valuable for fence posts, and for boat building. It is used for hubs and spokes of waggon wheels, and it is an excellent fuel. The locust timber that reaches market comes from the mountain slopes, where the locust-borer is thus far unknown. The range of the tree is all over the Eastern states and west to the Rocky Mountains. We shall not find them south of the latitude of Tennessee.

The catalpa’s great heart-shaped leaves, as broad as a man’s hat, come out in May, but the leafy shoots grow a foot or more in length, and it is well along toward Independence Day before the flower buds show streaks of white above the foliage mass. The upturned twigs end in a spike of blossoms, creamy in colour, but speckled within their wide throats with purple and yellow. The rim of the flower cup is daintily scalloped, and frilled, and the tree top is even more showy than the horse chestnut a month earlier.

There is stateliness, even stiffness, in the figure of a blossoming horse chestnut—a pyramid of green holding up a thousand pyramids of white. The catalpa has a round head, and the loose flower clusters are quite informal in their arrangement. The flowers nod gracefully on their stems—a thing the horse chestnut flowers are unable to do.

Why are the dots of colour sprinkled in the throat of the flower? Why are they arranged in lines that lead to the nectar sac? To guide the bees which come in swarms in answer to the signals of colour and fragrance the flowers fling out as lures to them.

The two stamens are ripe before the pistil. The bee rubs the pollen off by crowding into the flower. Some of this dust is bound to be rubbed off on the ripe stigma of an older blossom visited by this bee. Thus, unconsciously the bee helps the tree to set good seed. Of these we will study when we come to the tree again in autumn. Only a hint of the seed vessel is given by looking at the oldest flower in a cluster, and noticing the green part at the base.

The linden or basswood holds its arms out so that the broad leaves are exposed to the sun in slanting strata, or platforms of shade, that strike downward. The tree’s frame is roofed in with them in an almost unbroken thatch of green. Cattle love to crop this foliage, and to enjoy the dense shade on a hot day.

In July the dark green is illuminated by thousands of starry white blossoms, a few at the end of a slender stem that rises out of a pale green, leaf-like blade. There is nothing like it borne on any other tree.

The news that the basswoods are in bloom reaches the hives in good time. One is able to hear the murmur of bees as far as he can see the flowers, but the fragrance travels much farther. Basswood honey is higher in price than other kinds. Is this the reason the bees are so hard at work? Small as the individual flowers are, they have an unusual supply of nectar, and the bees revel in the plenty of what will feed them and yield wax. They make honey while the sun shines, counting the basswoods their best source of the crude materials for honeymaking. It was so in the days of old. Greek poets sang of the honey-laden lindens. Honey made from linden trees in the Lithuanian forests was carried to Rome, where it sold for three times the price of ordinary honey.

Bees swarm, and the new colony often takes to the woods and sets up housekeeping in a hollow tree. This is so likely in the Southern states to be a linden that “bee tree” is a familiar name of this tree.

THE EARLY BERRIES IN THE WOODS