172 



gration of the old stool, are able to develop vigorously and with- 

 out obstruction in all directions. In the case, however, of pollard- 

 shoots and frequently also in the case of stool-shoots, there 

 is, correctly speaking, no true reproduction. Here the normal 

 development of the individual tree has received a very severe 

 check, the individual has been badly wounded and injured by the 

 removal of its crown of foliage, and the plant sets about repairing 

 the injury as well as it may, just as we have seen is done in the 

 case of other wounds. Thus the tree at once endeavours to 

 replace the crown of foliage which has been removed by a 

 vigorous growth of pollard or stool- shoots. As a general rule, 

 it appears that the closer the resemblance between the new 

 crown of foliage formed by the young shoots and the old crown 

 of which the tree has been deprived, the better will the new 

 crown be able to fulfil its duty in providing for the healthy 

 maintenance and extended growth of the old root-system, i.e. 

 the more perfect will be the tree's recovery. In other cases the 

 process of recovery is slower and appears to resemble in a 

 general way that exhibited by a tree, the crown of which has 

 been severely damaged by drought or frost. In such a case, 

 if the injury has not been too severe, young shoots appear on 

 those portions of the stem and branches which are still alive. 

 These grow and gradually take the place of the dead branches 

 which ultimately fall off, and in a few years the recovery may 

 be so complete that we can see no signs of the damage remain- 

 ing. A very similar process often takes place in the case of a tree 

 which has been pollarded or coppiced ; the young crown of 

 foliage being unable to supply sufficient food material to the 

 old roots, many of the latter begin to die back from their tips, 

 while a crop of young roots is adventitiously developed from 

 those parts of the old roots which still remain alive. The 

 tree, as it were, appears to be trying to start life again with 

 a new crop of shoots and young roots. Just as a tree may 

 completely recover from severe damage by frost, drought, or 

 other injuries, so may it also satisfactorily recover from the 

 injury inflicted by coppicing or pollarding, but it should be 

 remembered that any demand made on the powers possessed 

 by a plant of recovering from an injury is usually very harm- 

 ful if repeated, and in Europe experience has shown that if ash 

 or maple are repeatedly cut over they often die after the 

 second or third operation. 



Propagation 150. Propagation by means of 



by means of layers and by guti are operations often resorted to by gardeners 

 GutiT * n I n di a m preference to propagation by cuttings, they being as 



