66 ENGLISH ESTATE FORESTRY 



different nature to that on the surface, or that pockets of 

 deep or good soil occur amidst shallow gravels and sands. 

 No greater mistake is made than that of assuming that the 

 surface soil is any indication of what is below, or that 

 either surface or subsoil can be gauged by the nature of 

 that existing a few yards away. An inspection of any 

 quarry, gravel pit, or railway cutting proves how rapidly 

 and constantly the soil varies after the first foot below the 

 surface, and it is such deep-rooted trees as the oak which 

 feel and are influenced by this variation. There is little 

 doubt that this accounts in a great measure for those 

 exceptionally fine trees which occur here and there in almost 

 every oak copse or plantation, and which are often 

 surrounded by inferior and stunted individuals of no great 

 value. Occasionally we meet with a clump of such trees, 

 or they may exist more or less regularly on an acre or two 

 of ground ; but it is seldom that any uniformity exists in a 

 mature oak wood such as we find with most species grown 

 under similar conditions, and there is a good deal of 

 probability that soil is largely responsible for it. 



But while soil may effect variations in the size of trees 

 grown on the same system, of equal influence are the 

 varying sylvicultural or arboricultural conditions which 

 surround each individual to a greater or less extent. Few 

 trees in any plantation receive exactly the same amount of 

 light, or are influenced in exactly the same way by the 

 light which they receive. On good soils and sunny 

 situations trees will bear more crowding than those grow- 

 ing under opposite conditions, and it is impossible to 

 regulate thinning in such a way as to ensure each tree 

 getting exactly what it requires. Oak being very intolerant 

 of too much shade, and its height-growth, on the other 

 hand, being easily checked by too much space and light, 

 the happy mean is almost as often due to chance as good 

 management ; and this is probably why small groups or 

 naturally grown clumps often show the best specimens of 

 oak timber that can be found. The outside trees of such 

 groups bend outwards and form a one-sided crown reaching 

 to the ground. The next row rises higher and suppresses 

 the lower branches of the tallest trees, which in their turn 



