SHAPE OF TEEES. 21 



greatly in this respect in mixture vritli other species which help 

 to crowd the wood. 



The locality, especially depth of soil, is not without influence 

 on straightness of stem. The Scotch pine alters its shape most 

 of all according to the locality in which it is grown, as while 

 in Norway, Poland, Finland and North Germany it grows as 

 straight as silver-fir and spruce, in the warmer regions of South 

 Germany and France it is often found crooked, even in dense 

 woods. A rapid upward growth during youth is prejudicial to 

 the Scotch pine in this respect, while a steady, moderate, and 

 long-continued upward growth is favourable to its straightness. 



Larch trees in the open, or growing rapidly on the borders of 

 dense woods, are often curved and acquire a sabre-like form ; 

 this is probably caused by the prevailing wind contending against 

 the soft upward shoots of the trees during youth. Fertile soil and 

 a shallow root- system favour this peculiarity more than poor and 

 stony soil, and the curve is confined to the lower part of the 

 tree. 



(c) Freedom from Branches. — As soon as the crown of a sapling 

 growing in a crowded wood has been formed, so that its lower 

 branches do not receive sufficient light for their foliage to thrive ; 

 they commence dying and dry-up, breaking off from the stem 

 and leaving the latter to a certain height, as a clean bole. This 

 clearance of the lower branches occurs in light-demanders, even 

 when grown in the open. Shade-bearing trees, on the contrary, 

 such as the spruce, may, in the open, retain side-branches down 

 to the ground, and the same may be said of the hornbeam and 

 beech among broad-leaved trees. It is therefore of the utmost 

 importance that a dense growth should be maintained in woods 

 during the whole period of upward growth of the trees. If after 

 this period the trees are allowed more room, this has no influence 

 on the cleanness of their boles, except that epicormic branches, 

 which can easily be pruned, may appear in the case of isolated 

 standard trees. 



Cleanness of bole, especially towards its base, is then among 

 the very first conditions for the production of valuable timber. 

 Early closing-up of woods is therefore essential, and all widely 

 spaced planting, especially of shade-bearing trees, should be 

 abandoned. Trees which have freed themselves only late in life 



