STRENGTH OF TREES 



only realize the beauty of a tree by watching a pine or ash 

 in a heavy gale of wind. The swing of the branches, the 

 swaying of the trunk, the balancing support of the roots 

 which, buttress-like, extend out into the soil, give some 

 idea of the extraordinary balance, toughness, and strength 

 in trees. Except in the case of the common umbrella, 

 which is an inefficient instrument in high wind, engineers 

 have never attempted the solution of the problem satis- 

 factorily solved by trees. A factory chimney only 51 feet 

 in height will have a diameter at the base of at least three 

 feet. This means that the height is about seventeen times 

 its diameter. But the Ryeplant, with a diameter at base 

 of 3 millimetres, may be 1500 mm. high! That is, the 

 height is five hundred times its diameter, and the Ryeplant 

 has leaves and grain to support as well as its own stem ! In 

 Pine forests on exposed mountain sides there is almost al- 

 ways at least a murmuring sound, which in a storm rises into 

 weird howls and shrieks. With Greek insight and imagina- 

 tion, the ancients supposed that spirits were imprisoned in 

 these suffering, straining pines. That is most beautifully 

 expressed in The Tempest^ where the dainty spirit Ariel had 

 been painfully confined in a pine tree for a dozen years, and 

 " his groans did make wolves howl and penetrate the breasts 

 of ever-angry bears.'"* 



One of the most interesting points in botany depends on 

 the fact that evil conditions of any sort tend to bring about 

 their own remedy. Endymion's spear was of " toughest ash 

 grown on a windy site"*' (Keats). The prosaic chemical 

 analyses of German botanists have, in fact, confirmed the 

 theory there suggested, for it is found that the wood of trees 

 grown in exposed windy places is really denser and tougher 

 than that of others from sheltered woods.^ 



^ Hartig finds the specific gravity of the wood in a tree is increased 



46 



