244 DISEASES OF TREES 



ing the cortex during winter. Young beech woods especially 

 frequently suffer very severely. If one allows the injured plants 

 to remain standing, most of them will develop in spring appa- 

 rently in a perfectly normal manner, because the sap is conducted 

 up through the wood as before. In the course of the summer 

 the exposed wood generally dries up, the outer layers being the 

 first to be affected, and wound-rot also makes its appearance. 

 Should the cortex have been removed right round the stem 

 above the collar, the plant loses the power of conducting water 

 at the injured part, and withers. If one delays cutting over the 

 plant till this has occurred, it seldom happens that any stool- 

 shoots are produced. If, on the other hand, one examines the 

 young plantation before the leaves appear, and cuts over all 

 injured plants close to the ground, vigorous shoots will be pro- 

 duced, at the expense of the store of reserve materials present 

 in the roots, and in a short time the young wood will be almost 

 as promising as before. The more vigorous plants may remain 

 alive for several .years, and adventitious roots may even be formed 

 above the wound, as is represented in Fig. 140. 



BARKING DUE TO THE DRAGGING AND CARTING OF TIMBER, 

 THE GRAZING OF CATTLE, &C. 



Abrasions of the bark which are caused during the process 

 of removing timber from the wood, especially on declivities, 

 are amongst the commonest form of wounds to which shallow 

 roots and the lower parts of stems are subjected. During the 

 dragging of timber, and especially when water is in active 

 movement in the tissues, large portions of cortex are detached 

 from the base of growing trees. Where cattle are grazed or 

 folded, and where roads occur in a wood, the shallow roots are 

 subjected to all sorts of injuries, and from these, in the case of 

 the spruce, the wound-rot ascends in the stem, attaining to a 

 height proportionate to the amount of moisture that enters the 

 wound from the soil. On this account wounds that are covered 

 by moss or humus are much more dangerous than those which 

 are perfectly exposed. 



The majority of the brown patches of red-rot that are observ- 

 able on the cut surface of the stool of the spruce, and which 



