CHAPTER IX 



TREES FOR WATER CATCHMENT AREAS AND FOR 

 GENERAL PLANTING 



Of equal importance with the selection of suitable situa- 

 tions for planting is the proper choice of species. A great 

 many kinds of trees have been tried in the British Isles ; 

 and so much information has been amassed concerning them 

 that there is no difficulty in assigning to each species its 

 exact value as a forest tree in this country. Some species 

 are of especial value for shelter. Others are suitable for 

 the formation of a protection zone at high altitudes. A few- 

 species, producing timber in a short period of years in great 

 quantity and of good quality, are fitted to constitute the 

 main crop. In any planting scheme regard must be paid to 

 the varying requirements of each species on soil and situation. 

 Conifers are chosen in the main for new plantations on 

 account of the ease with which they can be planted, and 

 because, as a rule, they yield large returns and can be 

 grown on short rotations. Nevertheless, there is always 

 room for valuable broad -leaved species. The ash, for 

 example, should be planted in small groups on patches of 

 good soil, such as occur in valleys and near streams. The 

 importance of the beech must always be recognised, on 

 account of the improvement of the soil which it effects by 

 its great shade and abundant leaf-fall. It kills the grass, 

 the great enemy to tree growth; and, mixed with main- 

 crop trees, it stimulates their vigour and increases their 

 production of timber. 



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