THE IVY 



A violent controversy rages as to whether it does good or 

 harm. Unhappily it does not do any good to trees. It 

 does not suck their sap, for its roots do not get through the 

 bark, but it does choke, with its clinging branches, young 

 tree-stems, and prevents their growing properly. 



Also, in winter storms an ivy-covered tree is much more 

 likely to be blown down. But on walls the ivy certainly 

 does good, for it sucks up the moisture, and ivy-covered 

 walls are much more dry inside than those which are exposed 

 to rain. 



Its method of climbing is very curious. All along the 

 stem quantities of little roots are produced. They dislike 

 light, like most roots, and creep into crevices and cracks, 

 where they wedge themselves in by growing thicker. Thus 

 the stem is anchored all along its length. It is curious to 

 find that these roots are formed before a twig is actually 

 touching the wall, so as to be ready for any emergencies.^ 



One interesting little point in the growth of the ivy on a 

 tree is perhaps worth mentioning. The main stem runs 

 nearly straight up the trunk, and when young is pulled 

 down into the crevices or cracks in the bark. But its 

 branches leave the main stem at an angle of forty-five 

 degrees or so to it ; these latter may often grow in this 

 direction for a foot or eighteen inches, but then they 

 gradually begin to turn more and more distinctly up the 

 tree. Still these branches firmly clasp the trunk like arms 

 spread out on either side of it, and make it almost impossible 

 to dislodge the main stem. 



Old plants of ivy entirely surround the trunk. The 

 flowering branches grow straight out into the air, and have 

 no tendency to cling to the bark. Their leaves are also 

 different. ^ Henslow, I.e. 



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