The Adventures of a Grain of Dust Part 22

I tell you there are some mighty queer things going on in the plant world, and perhaps Bud was right!

"Some peoples thinks they ain't no Fairies _now_, No more yet! But they _is_, I bet!"

HIDE AND SEEK IN THE LIBRARY

And, what is more, real live fairies have been found right down in the world of roots! The science people call them "Bacteria," but what of that? The thing about a fairy that makes it a fairy is that it is always changing something into something else. Isn't that right? Well, that's exactly what is done by the bacteria on the roots of certain kinds of plants--clover roots, for one; and the roots of beans, peas, peanuts, and alfalfa. These plants belong to the legume family, and if you will look up the word _Legumes_ you will find out all about these fairy factories on the roots.

Among other things you'll learn how small these fairies are. Why, 100,000 of the bacteria that live on clover roots, marching single file, wouldn't much more than reach across this typed page.[24] And in their little "villages" on one system of clover roots there are so many that all of them put together would make a city as big as London or New York; if the bacteria were as big as people, I mean.

[24] By the way, the funny thing is that, while the bacteria that live on roots of the legumes are plants and not animals, most of them _do_ move about.

Of course you have to take a microscope to see them--a very powerful microscope--and even then some kinds of bacteria you can't see until you put colored clothes on them. (Every high school boy who has worked in the "lab" knows how this is done.)

And when you finally see them, a strange thing happens. You've hardly got your eye on a little Mr. Bacteria before he's two!

"What's this! What's this!" you say. "Am I seeing double?"

You look again and he's _four_! But don't be alarmed, you aren't seeing double; it's just the little Mr. Bacterias multiplying by division. How they multiply by division is one of the interesting things you can learn by looking them up.

But it's a good thing that the bacteria people in the little nitrogen factories on the clover roots can get more farm-hands in this way, for they have a lot to do, and their work is one of the most interesting things that goes on about the place.

The article in the "Country Life Reader" on "The Smallest Plant on the Farm" will tell you how important these nitrogen farmers are.

You would hardly believe how great their work is, they're so quiet about it. Do you know what a human nitrogen factory is like? Well, for one thing, it's the _noisiest_ place in the world. Men, as do the bacteria, capture the nitrogen out of the air, but they do it by keeping up continual thunder and rain storms in big barrels.

You will find one of these factories described in an article in _St. Nicholas_, Volume 45, page 1137.

But what a fuss these human factories make! Why, in growing-time, out in the clover field, where the loudest sound you hear is the drone of the b.u.mblebee among the blossoms, the little bacteria people down among the roots are making nitrogen so much cheaper than the big noisy factories that it only costs the farmer about one-fifth as much as the storm-barrel nitrogen. And yet, of course, it often pays to buy the artificial nitrogen, too.

There are many more striking things about the habits of roots than I have had room to tell about here, which you will find in such books as Elliot's "Romance of Plant Life," Coulter's "Plant Studies," Coulter's "First Book of Botany," Allen's "Story of the Plants," Chase's "Buds, Stems and Roots," Atkinson's "First Studies of Plant Life," Darwin's "Power of Movement in Plants," France's "Germs of Mind in Plants," Gray's "How Plants Behave," Carpenter's "Vegetable Physiology," Detmer's "Plant Physiology," and Parsons's "Plants and Their Children."

[Ill.u.s.tration: THANKSGIVING DINNER OF THE DORMICE

They don't sit at the dinner table like that, to be sure, but along in the Fall and up to nearly the time of our Thanksgiving dinners, the dormice eat unusually heavy meals and put fat on their little bones to help them through the long, cold, and barren months of winter.]

CHAPTER XI

(NOVEMBER)

All-cheering plenty, with her flowing horn Led yellow Autumn, wreathed with nodding corn.

--_Burns: "Brigs of Ayr."_

There's silence in the harvest field, And blackness in the mountain glen, And clouds that will not pa.s.s away From the hill tops for many a day; And stillness round the homes of men.

--_Mary Howitt: "Winter."_

THE AUTUMN STORES AND THE LONG WINTER NIGHT

When the caveman was still living from hand to mouth; before he had even got as far as his first crooked stick for a plough, and when Mrs. Cave couldn't have canned a bean or a berry to save her life, even if she had had the cans, a certain little farmer already knew how to get root crops in the Fall and clean them and cut them and put them away in his little barn under the ground for Winter use.

Several of these forehanded folk we have already met--the beaver and the chipmunk, among others--but since we are now at the end of the harvest year I thought we might spend this evening--the last but one, I am sorry to say, that we shall be together--in a little chat about these thrifty brothers of the wild, and how some of them are going to spend the long Winter that begins in the Autumn and lasts until Spring.

I. LITTLE GRANARIES UNDER THE GROUND

I was going to begin by saying that one of the most _fore_-handed of them all has _six_ feet, but as that would be almost as bad as a pun, I decided not to. You would have known, of course, that by people with six feet I meant the insects.

ANTS THAT THRESH AND STORE

Among the six-legged farmers, you may be sure, there have always been many who took thought for the morrow--the ants, for example. One can believe almost anything of ants. If that sluggard had gone to the ant, as wise King Solomon told him to, and learned all their ways, he would have found, among other things, how one species harvests the seeds of the plant known as the "shepherd's-purse," by twisting off the pods with its hind legs. These members of the ant family store grains of oats, nettle, and other plants. They pick up all the seeds they can find that the Autumn winds have already threshed for them, but they're not the least like that lazy man who wouldn't have the corn that was offered by kind neighbors to keep him from starving, because it wasn't sh.e.l.led. If they don't find enough seeds on the ground when it comes time to think about the Winter stores they climb up and gather in the seeds themselves. On the shepherd's-purse, for example, the ant climbs up, selects a well-filled pod which is not sufficiently dried to have had its seeds threshed out by the winds, takes the pod in its little jaws and then--watch him--turns round and round on his hind legs until he twists it off! Then with it he carefully moves down the stem, like a baggageman carrying a big trunk from the third apartment; only the baggageman carries the trunk in front of him or on his shoulders, while the ant backs his way down. Sometimes two ants work together, one twisting, the other cutting away the fibres with its teeth. Sometimes they drop the pods to companions waiting below, and these other helpers never run off with it, but carry it to the common granary; for ants always play fair.

[Ill.u.s.tration: HOW THE ANTS WORK IN DIGGING OUT THEIR GRANARIES]

And they have granaries, these ant farmers--hundreds of them, made just for that, each about the size of father's watch.

[Ill.u.s.tration: THE INSIDE OF THE GRANARY

Underneath the dome of the ant house you see in the previous picture, are flat chambers like these, connected by galleries, in which the grain is stored. One is prepared not to be surprised at anything about ants, but listen to this: The Agricultural Ants not only gather and store this grain, but they actually plant and cultivate it. They sow it before the wet season in the Fall, keep it weeded, and gather it in June of the following year. Seems incredible, doesn't it? But I'm only telling you what McCook, an ant student, recognized everywhere as a reliable observer, saw these six-footed Texas farmers actually do.]

Now here's a thing; you stow away a lot of seeds in a little hill where, of course, there's moisture, and what's going to happen? Those seeds are going to sprout and grow and spoil, and this, of course, destroys their value as food. Then what are you going to do? Of course, a human farmer would put his grains in a dry granary where they couldn't sprout, but you see the ants haven't any granary of that sort; nothing but those little holes in the moist ground. Just what they do to these seeds has not been discovered. They do something that keeps them from either spoiling or sprouting. But, when they get ready for these seeds to grow, they let them grow; not so that they can raise a crop, but for the same reason that the Chinaman lets the barley sprout that he uses in making chop-suey; so that it will be nice and soft to eat. This growing digests the starch in the seeds into sugar. When the sprouts have grown as far as the ants want them to, they gnaw the stalk a little, and cut off the roots with their mandibles. When this sugar-making has gone on long enough the ants bring all the plants out into the sun and let them lie there until they are nice and dry. Then they put them in their barns, and as long as Winter lasts they live on this sweet flour, grinding it in their mouth mills as they go along.

Why, it's like living on cookies, almost! Only the ants have been used to this steady diet of sweets for ages, and it doesn't hurt _their_ little stomachs as it would ours.

[Ill.u.s.tration: CLEANING UP AFTER THE DAY'S WORK

While the Agricultural Ants don't take a bath after the day's work they do the next best thing. They give each other a kind of ma.s.sage, and they evidently find it very enjoyable. You know how the cat loves to be stroked, dogs and horses to be patted, and little pigs to have their backs scratched. The ants below are giving each other a ma.s.sage (left, abdomen; right, legs and sides). The lady above who seems to be braiding her back hair, is cleaning her antennae.]

This particular kind of a farming ant is called the Attabara, but there's another kind more wonderful still. If we want to call on them by their scientific names--these remarkable little creatures I'm going to tell about now--we'll have to go to Texas and ask if the _Pogononyrmex barbatus_ family are at home.

"Oh, to be sure," says the gentleman who first introduced them to scientific society,[25] "just come with me."

[25] Rev. H. S. McCook: "The Agricultural Ant of Texas."

So he takes us over into Texas and shows us the ants at work. They destroy every plant on their little farms except that known as ant-rice.

Compared to the size of the ants themselves, these grain-fields are giant forests, far bigger than the Sequoia Forests of California. The ants watch for rain at harvest-time as anxiously as a farmer, and on the first sunny day, they do their cutting and hurry the grain into the barn. Then on later sunny days, they bring it out to dry before finally storing it away.

"Well," you say, "is there anything left that these farmers _don't_ do?"

I can't think of anything except the planting. One observer says that they do actually plant the seeds, and Doctor McCook says, he wouldn't be surprised if they did, but he never saw them do it.