THINNING PLANTATIONS. 



period after a complete leaf canopy has been established, the 

 individual trees begin to press against each other, and later 

 on a struggle for existence commences, the stronger 

 specimens gaining the supremacy over the weaker. Here it 

 must be borne in mind that hard-wooded trees require 

 proportionately more room for their healthy development 

 than coniferous kinds, while length and clearness of stem, 

 produced by a due proportion of shade, is an object of prime 

 importance. It might, as some suppose, do little harm, to 

 let the struggle for existence go on unchecked, but there can 

 be no question that for several reasons it is wise policy to 

 allow the stronger trees every chance of succeeding, and to 

 cut away the weaker. The object should be to provide for 

 the trees left standing that amount of room or growing 

 space best suited for bringing about the particular conditions 

 aimed at, and in thinning, it must be the aim of the forester 

 to arrive at the happy mean neither over nor underdoing 

 the work, the former in particular. But while over crowding 

 is not to be tolerated, the danger of suddenly exposing the 

 trees to currents of air, to which they have hitherto been 

 unaccustomed, must be carefully guarded against, and it 

 should be distinctly borne in mind that to thin trees in an 

 abrupt manner is one of the greatest mistakes that it is 

 possible to fall into. 



Statistics compiled from a healthy Larch plantation, 

 growing on fair soil, and in a moderately sheltered position 

 in southern England, will now be given, and from which a 

 good idea of the age and size can be formed of the period 

 when thinning should be commenced. The trees when 

 planted were 2 ft. high, and pitted at 3 ft. apart. In four 

 years the outer branches began to touch each other, and in 

 six years from time of planting the average height of trees 

 was 7 ft. 10 in., and the shade occasioned had killed out most 

 of the grassy undergrowth. At this period of growth, the 

 disproportion in the size of the trees was, as is usually the 

 case, considerable, and left no doubt about which to remove 

 when the first thinning took place. Two years afterwards, 

 or in eight years from time of planting, thinning was first 

 engaged in, the taller trees at that time averaging nearly 



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