The Child's Book of Nature. Worthington Hooker
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as fast as they came out, you would, after a while, kill it. Sometimes worms eat up the leaves on trees. If this is done year after year to a tree it dies. I knew a man to strip off all the leaves from a grape-vine. He thought that it would make the grapes grow finely. He had seen people take off some of the branches from grape-vines, to make the grapes grow large and full. So he thought that if he took all the leaves off, the sap would all go into the grapes and make them very large. He thought, too, that the sun would make them ripen fast. But he found that the grapes stopped growing, and wilted, and dropped off. There are two reasons for this. The sun was too hot for the grapes when all the leaves were gone. And besides, there were some leaves needed to keep the grapes alive.
Leaves are lungs to plants.
Leaves are the same thing to plants that lungs are to an animal. The air that goes into our lungs helps to keep us alive and make us grow. So the air that is all about the leaves of a plant or tree helps to keep it alive and to make it grow. How this is done you can not understand now. I explain it in another book, which you will be able to understand when you are a little older.
The barter between lungs and leaves.
There is one thing about this that you can understand, which is very curious. The air does not keep the plants alive in just the same way that it does animals. You know that by breathing air we make it bad; and so we must have all the time a supply of fresh air. Now what do you think becomes of the bad part of the air that we breathe out from the lungs? The leaves all around us take it in. It is good for them. It makes them and the plants that they are on grow. They then, like our lungs, are all the time taking in air and giving out air. And leaves take what lungs give, and lungs take what leaves give. So lungs and leaves have a sort of trade together. They are always making this exchange with each other. And it is a good bargain for both. Both get what they want, and barter away what they do not want.
How it is carried on in winter.
But in winter, when the leaves are all gone except those on the evergreens, how is it with this trade between lungs and leaves? Lungs are all the time giving out bad air; but there are not leaves enough on the evergreens to take it all, and give back the good air. Well, what is to be done? A barter is carried on with the leaves a great way off in the southern countries. The air moves about so freely that this is easily done. The bad air goes there, and the leaves that take it into their pores give out the good air, which immediately spreads every where, even to us at the north. It is a free trade—as free as air, as we may say. There is not as much bad air made by lungs in winter as in summer, because many animals are either dead or torpid. But what is made is disposed of mostly in this way.
Questions.—How are leaves useful to us in giving out moisture to the air? What use of them is next mentioned? What is said of the shade made by leaves? Is this shade useful to fruits? What is the chief use of leaves? Tell about the man who stripped the leaves from his grape-vine. How are leaves like our lungs? What kind of barter is there between leaves and the lungs of animals? How is this barter carried on in winter?
CHAPTER XXI.
LEAVES IN THE AUTUMN.
The fall of leaves.
In the autumn in cold climates the leaves fall. This is the reason that the autumn is called the fall of the year. There are some trees that have leaves on them all the time. These are called evergreens. In very hot climates the leaves of trees and bushes are out all the year round. They have no particular time to fall. And some leaves stay on for many years. Those that stay on so long grow to be very large.
Evergreens.
If a tree or a bush that has its leaves fall in the autumn in a cold climate be raised in a warm climate, it will there keep its leaves on all the year. In the southern parts of Europe quince-trees are evergreen. The currant-bush, which, you know, with us is bare through the winter, in a hot country has leaves on it all the year.
Change of color in leaves in autumn.
Before the leaves fall, many of them, you know, become very beautifully colored. The variety of colors that you see in different trees is very pleasing to the eye. The maple-leaf is colored bright red, the oak a deep red, the walnut yellow, and other trees have their leaves variously colored.
Some trees change their leaves earlier than others, and some at first are only partly changed. So you see the green mingled beautifully with the bright red, yellow, and other colors. I have often admired a single tree standing by itself when it is partly changed. The maple is particularly beautiful. The top generally changes first. You often see the top bright red, and then the red is mixed with the green here and there in other parts of the tree. A little way off it looks as if the top were a cluster of red flowers. And the other parts of the tree look as if the flowers were coming out among the green leaves.
Brilliant and varied beauty of the forests in autumn.
When the sun shines brightly all the different colors of the leaves make the woods look at a little distance as if they were all covered with blossoms. It is a very splendid sight that you see when you look off from a high hill over the woods on the hills and valleys. It looks as if monstrous bouquets of flowers had been stuck down thick together in the ground.
Such a sight is especially splendid when the sun is nearly down. Then the light and shade vary the scene. Here you see the top of a tall tree standing bright in the sun, while the other trees around are in the shade. There you see a whole cluster of tall trees lighted up on one side. Here is a shaded spot, and there, close by, is a very bright spot, the sun shining upon it through some break in a hill. The colors in the lighted spots look the brighter for the shaded spots near by.
So, too, it is very beautiful when, with the sun overhead, broken clouds are passing quickly in the sky. The swift shadows of the clouds give constant changes to the scene. One shadow seems to be chasing another over a bed of flowers.
When the leaves put on these bright colors it is the beginning of their death. They soon fall to the ground, and decay, and become a part of the earth. Some one has said that flowers are God’s smiles. So we may say that God smiles upon us in the dying leaf, when he makes it so much like a flower.
What makes the colors of the leaves in autumn.
How it is that all these different colors are made in the leaves in the autumn we know not. It is said that the frost makes them, but no one can tell how it does it. And, indeed, it is probably not the frost alone that thus paints the leaves, for the change sometimes begins before any frost is perceived. We do not understand how this effect is produced any better than we do how the various colors of the flowers are made.
Forests in England.
It is singular that in England the leaves do not appear in these very bright colors in autumn, so that an Englishman is astonished at the beauty of our forests in that season of the year. Now why it is that the leaves are not affected there, in the same way that they are here, we do not know. It is supposed that it is because there is more dampness there than there is with us. Whatever may be the cause, it makes a great difference with the beauty of autumnal scenery. We should hardly be willing to exchange the brilliancy of an American October day for the dull colors presented by the forests in England.
Questions.—Why is autumn called the fall of the year? What are evergreens? What is told about quince-trees and currant-bushes? What is said of the colors of leaves just before they fall? Tell about the maple as its leaves are changing. How do the forests look in the bright sun when the leaves are changed? How do they look just before sundown? How when shadows of clouds are passing over them? What is said about God’s making the dying leaves so much like flowers? Do we know how the colors are made in the leaves in autumn? What is said about the leaves in England?
CHAPTER XXII.
LEAF-BUDS.