330 Remarks on the Fall 



by excluding from the trunk and branches the light of the 

 sun, and preventing a free circulation of air round their 

 surfaces. Even practical woodmen, who maintain that ivy 

 proves beneficial by " keeping the trees warm," have before 

 now acknowledged to me that it is injurious to the bark ; 

 which, they allow, is hereby prevented from attaining its usual 

 thickness and substance. But all this, it will be urged, is little 

 more than mere theory and plausibility of argument, which 

 ought to be employed cautiously and with a sparing hand in 

 such a matter-of-fact affair as natural history. What I would 

 chiefly insist on then, is the fact, that deep weals are often in- 

 flicted on the solid wood, positive grooves, occasioned by the 

 tight pressure of the ivy.* Young trees, also, or at least trees 



* Mr. Bree has sent a length of 6 in. of one of the branches, about 

 4£ in. in diameter, of the fallen ash tree, for the purpose of exhibiting the 

 effect of the ivy's constriction on the ash tree's bark and wood. Into the 

 bark and wood of the cylindrical log sent are impressed two weals or 

 grooves, each an inch or more in breadth, and from half an inch to near an 

 inch in depth ; and the weals or grooves have a course so gently spiral, 

 that not quite two coils take place on the log's length of 6 in. The depth 

 of the grooves is, in part, produced by the bark and wood having, from the 

 tightness of the ivy's constriction, risen, like the banks of a channel, into 

 a ridge on each side the grooves which the branches of ivy, one in each, had 

 first occasioned and then occupied. The bark of the ash at the bottom of 

 these grooves is dead, dense from pressure, and scarcely the eighth of an 

 inch in thickness : still the wood beneath it is quite alive. 



That the ivy, and other twining shrubs, both deciduous and evergreen, 

 do cause by their constriction more or less of injury to most of the trees 

 and shrubs about which they entwine themselves, is not to be disputed. 

 Shakspeare (as quoted by Smith in his English Flora, vol. i. p. 326.) has 

 truly and tastefully remarked — 



" So doth the woodbine, the sweet honeysuckle, 

 Gently entwist the maple." 

 Gentle, howsoever, as are the first embraces of the honeysuckle, and of 

 other twining shrubs, while their stem or branch is yet tender, and, through 

 its tenderness, powerless ; they become, with the age, size, strength, hard- 

 ness, and consequent incapacity for dilatation, of their stem or branch, 

 effective agents of an obviously injurious constriction ; for the coils of 

 woody-stemmed twining plants are scarcely in any, perhaps in no, species 

 enlarged in capacity so fast as is the diameter of the trunk, stem, or 

 branch, which these coils encircle ; that is, presuming the supporting tree 

 or shrub to be in a healthy and freely growing condition. 



Cowper, whose notices of nature are most accurate, gives coincident 

 evidence, and most eloquently deposed, on this fact, in the following lines : — 



" As woodbine weds the plant within her reach, 

 Rough elm, or smooth-grain'd ash, or glossy beech, 

 In spiral rings ascends the trunk, and lays 

 Her golden tassels on the leafy sprays ; 

 But does a mischief while she lends a grace, 

 Straitening its growth by such a strict embrace." 

 Cowper was one of those whose mode of apprehending was such as 

 " Draws us a profit from all things we see ; " 



