132 THE DEVELOPMENT OF BRITISH FOUESTRY 



consist of sand and gravel is difficult to say without an 

 exhaustive examination of the drift maps of the Geological 

 Survey. It may be taken more or less for granted, 

 however, that surfaces free from peat below 500 feet or so, 

 and which are returned as mountain and heath lands in 

 official returns, must be of that type, and probably most 

 of the mountain below 1000 feet is either of this class or 

 that classified under the second head. These soils are 

 usually under rough pasture, and in a more or less un- 

 improved condition, and are better adapted for forestry 

 than anything else. 



In mountain districts, however, these surfaces generally 

 adjoin peat-covered land, and official returns do not assist 

 one in forming any relative estimate of the extent of 

 surface under one class or the other. In the lowlands, 

 and keeping away from the low-lying bog areas in 

 Scotland and Ireland, the greater part of the heath land 

 may be estimated as plantable, and capable of growing 

 timber of some kind. The south, midlands, and east of 

 England, exclusive of parts of Cornwall and Devonshire, 

 might be said with little exaggeration to contain no land 

 incapable of producing timber. By far the greater pro- 

 portion of these districts is under intensive agriculture, 

 but probably from 2h to 5 per cent, is, from a purely 

 economic point of view, capable of profitable afforestation 

 in the sense that rough grazing is the only agricultural 

 use to which it can be put. 



On certain calcareous formations, however, especially 

 chalk, oolite, etc., the surface soil is too thin and the subsoil 

 too impervious to carry profitable crops on the hill-tops, 

 although they seldom exceed 800 or 900 feet elevation. 

 Beech, larch, and such pines as Scots, Austrian, and 

 Corsican, appear to be the only trees able to thrive 

 sufficiently long to produce small timber on this class of 

 land, and no evidence can be shown that would indicate 



