THE IVY. 



287 



fibrous roots. These are to be distinguished from 

 the tufted fibres, by the aid of which the plant 

 clings to a wall or trunk of a tree. The former 

 are proper roots, and are only pushed forth from 

 those parts of the stem w^hich are opposite to the 

 leaves, and only appear when they can be em- 

 ployed with advantage in the support of the plant. 

 The tufts of fibres, on the contrary, are produced 

 from all parts of the stem which are nearest to the 

 wall or tree, and are invariably absent when the 

 plant crawls along the ground and therefore has 

 no use for them. Consequently the opinion that 

 Ivy is injurious to trees, by inserting its roots 

 into the bark and absorbing their juices, is erro- 

 neous. It may sometimes happen that a tree is 

 clasped too closely by matted Ivy-bands, and is 

 thus prevented from developing its full growth, 

 or, more rarely still, the weight of its ma.ssy head 

 may overstrain the branch which supports it, and 

 be the occasion of ruin to both; but, except under 

 such circumstances, it does no mischief. 



A remarkable instance of the compressing 

 power of Ivy is cited in the Gardeners' Chro- 

 nicle," proving that a netted mass of Ivy does not 

 simply prevent the expansion of the body which it 

 clasps, but as its stems increase in bulk, actually 

 contracts the space enclosed. On removing some 

 Ivy from an old house at Carshalton, it was dis- 

 covered that a thick leaden water-pipe had been 

 in many places deeply indented and in some places 

 squeezed fiat by the stem of the plant. Trees 

 that have long been coated with a net-work of Ivy 

 should not be stripped all at once, lest they should 

 be injured by sudden exposure to cold; and when 

 it is desired to keep young trees in plantations 



