INTELLIGKNCK IN TRFJES. -ll 



INTELLIGENCE IN TREES. 



C. S. HARRISON, YORK. 

 THE TUEE AS AN ENGINEER. 



The better we are acquainted with a tree the more we appreciate It, 

 and we are at times astonished by an intelligence which seems to be 

 almost on the border of reason. 



Take one standing out in the open. It is seventy-five feet high and 

 the limbs have a spread of fifty feet and it is filled with leaves, the 

 whole presenting an immense frontage to the winds which are blo\ying 

 at the rate of sixty miles an hour. 



Just hand that problem over to a civil engineer, the best educated one 

 you can find. Tell him of the immense leverage the tree gives to the 

 wind and that the base where it touches the earth is only four feet 

 through, and he must strengthen it that it will not blow over. What 

 would he say if you told him he must erect a house seventy-five feet 

 high and fifty feet broad, all on a base of only three or four. He would 

 tell you it could not be done. That to be safe you want a foundation 

 as broad as the house itself, and that it was not in the power of human 

 skill to meet a problem like that. 



And yet, that tree without having been to school, without studying 

 engineering, and without a knowledge of the higher mathematics, 

 quietly goes to work and solves the problem without a mistake, and 

 the most difficult problem too. 



While in Illinois I bought a place on which were sturdy oaks that 

 had to be grubbed out. I learned better than to cut down the tree first. 

 I wanted the leverage of the top and it made a wonderful difference. 

 Then I could study the marvelous feat of engineering. What a huge 

 bulge there was at the base where those tremendous brace roots went 

 out to clutch the earth like tent cords. There was the tap root which 

 bored its way deep into the ground. If you followed out these lateral 

 braces you would find them like cables of steel throwing out an almost 

 infinite number of small roots and these would wander out like net- 

 work, a hundred feet away. Now let the tremendous root pressure 

 come. How tough the trunk is. If not well woven it would snap like a 

 pipe stem. Let the top bend and sway, ten thousand little cords covering 

 the whole area of a circle of 200 feet around the tree are converging 

 in the main braces and clutching the earth, and each telling the other 

 to hold fast, and they do. The storm wages with redoubled fury. The 

 great mass sways and bends before it. Each limb is a canvass to catch 

 the gale. What a mighty battle between the storm and these unseen 

 tent cords which are holding the tree. Every fibre has been toughened, 

 and the process of resistance has made the tree stronger for future emer- 

 gencies. 



If you go into a dense forest you find another condition of things. 

 The trees standing on the outskirts are the sentinels which guard the 



