82 ON THINNING PLANTATIONS. 
met with ; indeed, knots of any importance are seldom seen, 
except where such were attached to live branches at the time 
the trees were felled. The wood of the old trees appears so 
clean and equal when sawn up, that in many, only very slight 
marks of lateral branches are visible. The young trees of 
from twenty-five to forty years’ growth present regular tiers 
of decayed branches near the ground, which fall away in course 
of time. 
“The proprietors of the native forests sometimes prune 
and thin the woods, but not often; they thin when the trees 
are much crowded, and of nearly an equal size, especially when’ 
situated near a road or river, where timber is of most value ; 
but this is not attended to in the more remote parts of the 
forests. I have only seen the trees pruned when they stand 
quite thin, or from having lost their leading shoots, by sheep 
pasturing the ground, or other casualty, have become bushy. 
In this case I have seen a considerable extent gone over in 
January and February, and pruned to the height of from two 
feet to four feet with the axe; the whole height of the trees 
being from five feet to ten feet. In the Highland natural 
forests the young plants do not often rise of equal strength 
and size. There is commonly a portion of them (a sufficient 
crop) stout enough to overtop the smaller ones; and the 
latter are of much benefit in preventing the side-branches of 
the former from advancing to a large size. The side-branches 
of the true Highland pine naturally take a wide or horizontal 
direction, whereby they are more subject to decay by the 
closeness of the trees than if they inclined to a more perpen- 
dicular figure, as do our low-country pines. In planted woods, 
the pine-trees are commonly of the same size and age; and 
then it is absolutely necessary to thin them as their tops rise 
equal, and form a surface parallel to that of the ground on 
which they stand ; therefore, without relief by thinning, the 
whole are to a certain extent injured; whereas in natural 
forests the difference of sizes and ages is great, and the 
strongest prevail unhurt. I am acquainted with many artifi- 
cial plantations of pines ; and the common method is, to thin 
