The Study of Plant Life - M. C. Stopes (korean ebook reader TXT) 📗

you try to pull it up you will find that the roots are long and fine, but strong, and that they grow for great distances into the soil, so that it is very difficult to get the plant out. The leaves are small and tough, and the lower ones on the stems generally have their edges half rolled in, while the leaves on the ends of the branches which stand further out in the air are often so much rolled as to be almost entirely closed. Some of the heather-plants seem to be covered over with short hairs like soft down, while others have shiny strong leaves. In fact, the heather has many of the characters of plants which have to protect themselves from drought.

Look at the others growing with the heather; there is the heath, which is so like it that almost the same description applies to it. Then there is the cranberry, which lies close to the ground, and is somewhat protected by the other plants, and has more delicate stems, and larger, flatter leaves, which are also rolled in at the edges. The bilberry has certainly larger leaves than these others, but notice in the early autumn how soon and readily they drop off, and leave the thick, green, ridged stem to do their work. The moorland grasses also have protected leaves; generally they are narrow and pointed, and the whole leaf rolls over, so protecting the side on which are the transpiring pores (see p. 102). All these plants have the appearance of protecting themselves from loss of water; how is it? It may seem strange when you remember that it is from our moorlands that so much of our water supply comes, and also that the moors are common in the north, where there is a large rainfall. All the same, the plants on a moor do actually require to preserve their water, as they suffer from “drought conditions.”

Stand on a high moor on a windy day, and you will soon feel how the force of the wind sweeps across it. Such a day is what laundresses call “fine drying weather,” and so do the plants. Then if you go on a bright sunny day in summer, you will soon feel how very hot the moorland can be, for there is no shade to be had anywhere, and the cool green glades of a wood offer a tempting change. The moorland plants suffer from this heat, and require to protect their transpiring pores from the glare, so that you will find all those that can do so, have rolled their leaves up tightly. Then notice the soil of the moors, how springy it is, and how black and “rich”; very often there are traces in it of the partly decomposed plants which form it. This is what is called a peaty soil, and may even be true peat. The decomposing plants in this soil give rise to an acid which is rather preservative, and at the same time it acts on the living plants and makes it difficult for them to draw in water by their root hairs. This kind of soil adds very greatly to the “drought conditions” of the moorland plants, for it makes it hard for them to use the water which surrounds them. All these things cause the moorland plants to be as sparing as possible of their water, and so they have the appearance of plants grown under dry conditions.

But why are there no trees on the moors, you may ask! It cannot be that they are on too high a level for trees to grow, for some even higher hills are clothed with them. The truth is that probably long ago there were trees on the moors, but men cut them down foolishly without having planted young ones between the old ones, which would have replaced them. When once all the trees are cut down on a hillside, it is very difficult for young ones to get a start again, because everything which makes it hard for ordinary small plants to grow hinders the young trees, and the worst of all these things is the strong wind, which can rush unchecked over the bare moor. A strong wind is more powerful than a young tree, and kills it.

The plantations of young trees which are to be found on the moorland have to be started on the sheltered side, and require much care and attention. You will notice that the trees which do grow there are those which are specially fitted for a hard life, such as the pine, larch, and birch.

Another feature of the moorland, and one which cannot long escape our notice if we walk about moors at all, is the number of patches of wet moss which shake and tremble beneath our feet, and may form great stretches of bog-land. Sometimes this is so soft that it gives way altogether, and one may be knee-deep in moss and water, where it looked firm enough to the eye. You will find this bog moss grows in a peculiar way, the fresh green branches growing up and up, while below lie the half dead older stems, which are partly preserved by the peaty acids. These layers of moss collect for many years, till very thick masses of peat-bog may be formed.

Among the bog-moss you will often find the sundew and butterwort (see pp. 114-15), which are two of our chief insect-eating plants. They love the boggy moorland, or a damp spot beside a little moorland stream.

There is a curious thing you may have the chance of seeing in a wet moor. If you find a stream dripping over a ledge some little distance on to the rocks below, you may see how thick and beautifully green are the patches of moss growing beneath its spray. If the stream has passed over much limestone (and is therefore carrying some in solution), you may see below the living moss much dead moss just covered with a thin coating of lime. Below this is more moss, which has been made quite hard with the lime, and is brittle and snaps if you try to bend it, while below this again is a hard, compact mass of stone which is made from the stony stems of the moss crushed together by the weight above them and filled in with more deposited lime. In some places great masses of rock are formed in this way. You have here, acted before your eyes, a piece of the history not only of the living and dying plants of to-day, but of the building of rocks, which may some day help in the building of mountains.