PLANTS OF THE MOORLAND 99 



sarily put an end to the supply, unless the peat-cutters 

 are too greedy. For more peat must always be made. 

 What is likely to put an end to peat formation is 

 drainage, especially if that means the introduction of 

 water from a surrounding area. But as long as a big 

 hummock of Bog Moss keeps a lot of stagnant water 

 about it like a sponge, the oxygen in the water is not 

 replaced, and peat formation sets in. 



In order to understand better what peat is not, a 

 little must be said in regard to soil-making in general. 

 The weathering of the rocks may be said to produce 

 earth, but this requires to be mixed up with the 

 results of the decay of plants (and animals too) before 

 it is worthy of the name of soil. Everf very simple 

 plants, such as Algae, Fungi, and Lichens, help a little 

 in this soil-making, which one can recognise by the 

 colour of the earth becoming darker. One sees the 

 beginning of this even at the top of the mountain. 



When the leaves of plants fall to the ground in a 

 shady wood, or in any place, not very dry and not 

 very wet, where earthworms are abundant, the forma- 

 tion of vegetable mould begins. The earthworms 

 swallow the decaying parts of plants along with the 

 earth, and they digest part of the vegetable matter. 

 The undigested and indigestible stuff is voided on 

 the surface in the form of worm-castings, and thus 

 fertile soil is made. There are many processes going 

 on at once : the vegetable matter is changed into 

 more available form and it is intimately mixed up 

 with earth, the soil is made to circulate in its surface 

 layers, and it is ground to powder in the gizzards of 

 the earthworms, the burrows make and keep the sur- 

 face soil looser, opening it up to the air and the water. 



