IMPORTANCE OP THINNINS. 411 



an inch of timber were formed in five years. Had this tree 

 been properly treated, it ought, by the end of thirty-five years, 

 to have been eighteen inches in diameter, instead of ten inches 

 and a half. 



But, bad as are the consequences of a crowded growth to the 

 formation of timber, and also to its quality, it is not the only 

 evil. Plantations which have been crowded for many years 

 cannot afterwards be thinned successfully. The trees become 

 bark-bound and rootless, and are blown over by the first storm. 

 Eoots, like timber, are formed in proportion to the quantity 

 of foliage, and to the space a tree has to grow in. A tree 

 whose trunk is divided into limbs, loaded with healthy leaves, 

 fixes itself to the soil by gigantic roots, which hold it immove- 

 ably, and help it to defy the storm. But a tree drawn up to a 

 pole, with a few limbs at the summit, has neither the means of 

 forming roots, nor the space in which to develope them. A 

 few fibres are all that it produces, bearing no due proportion to 

 the head ; and the moment the protection of the trees around 

 it is withdrawn, it necessarily falls over. 



As to the manner of thinning plantations, it does not 

 appear possible to give particular rules for such an operation. 

 Instead, therefore, of saying that when a tree is of such a 

 height it ought to be at such a distance from those around it, 

 it seems better to state as a general rule, that no one tree 

 should be permitted to touch another, but that they should be 

 allowed to remain as close as circumstances will permit, pro- 

 vided thei* branches do not touch. Practically, it is impossible 

 to adjust the thinning of a plantation with much exactness ; 

 and in the annual removal of such trees as are touching others, 

 spaces larger than are actually requisite, according to this rule, 

 will be formed. This is, however, an advantage, because it 

 allows the wind to find its way freely among the trees, and 

 give them sufficient room to spread their roots about. 



The planter should be careful to mark during summer the 

 trees that are to be removed in winter ; because it is only at 

 the former season, when trees are covered with leaves, that it 

 is possible to ascertain ia what degree deciduous trees really 

 interfere with each other. 



