SOIL AND SURFACE CONDITIONS 141 



next step in the process of reclamation consists in the 

 breaking up of the tough fibrous surface which invariably 

 characterises dry or drained peat, and which is practically 

 as objectionable from the planter's point of view as the 

 wet, spongy form. This tough layer usually consists of 

 the roots of such plants as heather, sedge, rushes, and 

 species of grasses, and occasionally bracken and gorse. 

 Tree roots placed in this layer might almost as well be 

 lying between two sheets of leather, for all the good they 

 are likely to get out of it, until their roots strike beyond it 

 into the soil below. In dry weather the peat contracts and 

 opens up, leaving the roots almost bare. In wet weather 

 and winter the sodden peat surrounds the roots on all 

 sides, charged with humic and other acids, which are 

 anything but conducive to root action. A few of the 

 species above named may be able to secure a weak footing 

 in this substance, but the majority of trees die out 

 altogether after a few months or years. When the 

 surface is thoroughly broken up, either by taking off two 

 or three feet en bloc, which is the most satisfactory but 

 extremely expensive method, or by covering it with some 

 growth which will kill out the surface plants, a mild form 

 of decomposition or weathering is set up which renders 

 the peat somewhat more suitable for tree-growing. The 

 action of frost freezes the moisture in the upper few 

 inches, and probably plays an important part in breaking 

 down fibrous peat into a loose mould, but this action is 

 impossible till the surface growth is destroyed. The most 

 satisfactory surface covering for effecting this is probably 

 a thick crop of some easily satisfied tree, which will 

 produce a dense shade and surface covering of dead 

 leaves, and kill out all surface vegetation after a few years. 

 Trees such as these have been found in birch, mountain 

 pine, Banks's pine, white American spruce, and others 

 capable of thriving in the peat after a certain amount of 



