214. OUR FORESTS AND WOODLANDS 
bole picturesquely topped with a sparse crown 
of tufted foliage. 
Pure woods of pine are usually found only on 
the poorer classes of dry soil, where pine is often 
the last resource of the forester; and in such 
unfavourable situations its growth is naturally 
not so vigorous or profitable as under more con- 
genial circumstances. Here it may have to be 
harvested at about seventy or eighty years of age 
with a poor yield of about 3000 cubic feet per 
acre, while the better classes of pine soil will 
show considerably more than twice that stock, 
and at the same time make it profitable to delay 
the fall for other twenty to forty years. 
On land above the average in quality pine 
thrives well in admixture with other kinds of 
trees, needle-bearing or broad-leaved, so long as 
these are of somewhat slower growth, permitting 
it to have its crown free from overshadowing. 
Here it grows more vigorously, forms a better 
bole, and has a larger proportion of good red 
heartwood than if grown in pure crops, while it is 
less liable to be broken by snow or to suffer from 
attacks of noxious insects and fungous diseases. 
But on inferior classes of land it is often simply 
