HOW TO PEUNE. 229 



as to be mostly unobservable, unless in a valley where 

 they are looked down upon. Where good forestry is 

 carried out, this department is always attended to, and 

 is one of the most useful branches of pruning. All 

 such contending shoots are cut off close to the stem, 

 unless in cases where the operation had been so long 

 neglected as to leave a bare side of the tree. In the 

 latter case, instead of cutting quite close to the stem, 

 the contending branch may be cut at any convenient 

 distance from it, for the purpose of maintaining the 

 symmetry of the tree. 



PRUNING PINE AND FIR PLANTATIONS. 



Much has been said on this branch of the subject, 

 and ably discussed amongst practical foresters. 



In the growth and culture of pine and fir planta- 

 tions, the natural result is, that as the upper tiers of 

 branches grow, the lower ones wither and decay. This 

 is caused by the side branches being confined and 

 limited in space. It is a common thing for pine and 

 fir plantations at thirty years old to stand about 8 

 feet apart, which gives each branch a spread of only 

 about 4 feet ; and as the upper tiers attain their full 

 extent of growth, the lower ones naturally die. When 

 undisturbed by thinning, and the area of plantation is 

 of considerable extent, the branches rot and drop off 

 of their own accord ; but if by undue admission of 

 light and air, as produced by thinning, the branches are 

 thereby induced to harden, they remain for years upon 

 the tree before falling off, and thus impart to the 

 future timber knots of a very injurious and hurtful 

 kind — what the wood-merchants call black knots (see 

 fiCT. 7, p. 224), which detract very seriously from its 



