METKODS AND PRACTICE 161 



grow quite fast enough, and occasionally too fast. With 

 the exception of Scots pine they are, however, easily 

 pruned back and kept in check, and with proper attention 

 no serious injury should follow their use as nurses. Scots 

 pine is, however, a more doubtful nurse tree, as its wide 

 crown development, after the first five or six years, often 

 renders it objectionable. 



Several other species than the above, however, might be 

 mentioned which are not commonly considered as nurse 

 trees, pure and simple. These are Japanese larch, Banks' 

 pine, and mountain pine. The two former species are 

 remarkable for their rapid growth when young, but the 

 latter never attains a great height, and is chiefly valuable 

 in suppressing a surface growth of heather or other trouble- 

 some plants not easily killed out. The objection to Japanese 

 larch so far is that it is still too expensive to purchase on 

 a large scale, but its ability to grow rapidly for a time 

 in almost any soil will compensate for that drawback in 

 the eyes of most planters. As a timber tree, the Japanese 

 larch will probably prove a failure, though no one can say 

 that this is yet certain. But for making a quick start, 

 covering the ground rapidly, and producing a humus 

 layer on the surface, it has few equals. Banks's pine 

 has the merit of being a cheap tree, and also gets away 

 rapidly on British soil. As a nurse for Corsican or 

 Weymouth pine it might prove useful on poor soils, 

 although it is perhaps not such an improvement on the 

 Scots pine after all, and has little or no timber value. 

 The chief value of mountain pine depends upon its soil- 

 shading qualities, and for this purpose it is largely used 

 in Danish forestry. In Britain it is seldom planted on a 

 systematic scale, but for heathy and peaty soils on exposed 

 sites it is possible that the planting of this tree might 

 have good results as a mixture with spruce, silver fir, 

 and Scots and Corsican pines, provided the latter are 



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