How does it find the worms and grubs? Well, of course it cannot see underground; so sometimes, we may think, it smells them, for its scent is certainly very keen. But oftener, most likely, it hears them moving about; for its ears are even keener still. Haven't you noticed that, although you may often walk through fields which are almost covered with molehills, you never see the earth being thrown up? That is because the mole hears you coming. It hears your footsteps when you are a hundred yards distant, or even more, and immediately stops work until you have gone away again. In "The Tempest," Caliban tells his companions to "tread softly, that the blind mole may not hear a footfall." Although Shakespeare was wrong in thinking that moles are blind, he was quite right in reminding us that they have very sharp ears.
Friend or Foe?
The gardener, of course, looks upon the mole as a foe; and so it is when it drives its tunnels under our lawns, and throws up great heaps of earth on the surface of the grass. And the farmer regards it as a foe too, and kills it whenever he has an opportunity. But perhaps the farmer may not know what a busy little animal the mole is, and what thousands and thousands of mischievous grubs it devours. There are wireworms, which nibble away at the roots of plants till they kill them, and then move on to destroy other plants in the same way. There are "leather-jackets," or daddy-long-legs grubs, which feed upon the roots of grass, and sometimes ruin all the turf in a meadow. There are also the great fat white grubs of beetles, which are worse, perhaps, than either; and many others as well. Now the mole is always preying upon these. It eats them in hundreds every day of its life. And just think of all the mischief that they would have done if they had been allowed to live! No doubt it is annoying to the farmer to have molehills among his hay, which blunt the knives of the reaping-machines, and prevent them from cutting properly. But even that is better than having no hay to cut; and there would be none if all these mischievous grubs were allowed to live.
But there is another way as well in which the mole is useful; for the earth which it digs up from down below, and throws up in heaps on the surface of the ground, serves for what the farmer calls a top-dressing. After a time, you see, the nourishment in the soil at the surface is sucked out of it by the roots of the grass. If it were in a garden, the farmer could dig it. If it were in a corn-field, or a turnip-field, he could plow it. But in a meadow, he can do neither, without destroying the pasture. So he applies a top-dressing. He gets some good, rich earth from elsewhere, and spreads it over the surface; and this earth works down to the grass-roots, and gives them just the nourishment they require.
Now this is exactly what the mole is always doing. The earth which it throws up is fresh, rich earth from down below, which the roots have not reached. It is just what the failing grass requires. And if the farmer rakes the molehills down, so as to spread this earth evenly over the surface of the field, he finds that it forms a top-dressing quite as good as any he could apply himself. So instead of looking upon the mole as one of his enemies, he ought to include it in the list of his laborers.
The Little Well-Digger
Another thing that we must tell you about the mole is the way in which it obtains water. It is a very thirsty animal, and constantly requires to drink. At the same time, it cannot leave its burrow half a dozen times a day, in order to visit a stream or a pond, for it would almost certainly be killed by one of its many enemies. So it actually digs little wells of its own, always doing so in the dampest parts of its tunnels, where they fill up almost immediately. And when it wants to drink it just goes off to the nearest of these wells and satisfies its thirst.
The Mole's Fortress
But the most wonderful thing that the mole does is to make what we call a fortress, surrounding the chamber in which it sleeps. This fortress is situated either in a natural mound of earth, or else beneath the spreading roots of a tree or a large bush; and it is made in this way: First the mole digs a short circular gallery. A little way under this it digs another, rather larger in diameter, and connects the two by means of five short passages. In the middle of the mound, and about half-way between the two galleries, it scoops out a large round hole, from which three passages run to the lower gallery. This is the mole's bedroom, and it communicates with the main burrow by a tunnel which dips under the lower gallery. Finally, a number of runs branch out from the lower gallery in all directions.
So, you see, if a mole is chased by an enemy, it can nearly always escape by passing through its fortress. It goes up one passage, down another, up again by a third, down again by a fourth, and then off by one of the side runs; so that its pursuer is almost sure to be bewildered. And if the little animal should be surprised while asleep, it can escape in any direction without losing even a moment.