4 o6 SCIENCE PROGRESS 



are characterised by certain differences in behaviour. There 

 is, first, a period of rapid growth, when, in the case of a tree, 

 branch-formation is prominent, corresponding with the increase 

 of stature in the case of animals. In the second period branch- 

 formation becomes insignificant ; the tree has attained its limit 

 of size and such wood-formation as occurs goes to increase 

 the substance of the stem and branches already in existence. 

 This is the period of full bearing. Such new shoots as are 

 formed at the time are rather fruiting twigs than future 

 branches ; the general outline of such a tree will remain 

 practically unaltered during twenty or thirty years. It is only 

 when a branch is removed that anything approaching to branch- 

 formation will occur, the tree endeavouring, as it were, to 

 repair the damage done. The pruning of a tree at this stage, 

 therefore, will result in the formation of a greater length of new 

 wood than would otherwise have occurred. As an instance 

 may be quoted the results with two similar fifteen-year-old 

 apple trees on the paradise stock : the one which was not 

 pruned formed twigs totalling 2,200 in. in length during 

 the season, whilst the other, which was pruned, gave growth 

 to twigs measuring 6,700 in. 



It may be added that a third period in the life of a tree 

 may be recognised — that of senile decay— which is generally 

 characterised by a strenuous attempt to reproduce its species 

 before death, as evidenced by the bearing of heavy crops of 

 small fruit — worthless, however, from the point of view of the 

 grower — and by sending up of numerous suckers from the roots. 



Method of Cutting the Branches 



Of the technical details of pruning very little need be said 

 here. It is generally held to be of importance to prune back 

 to a bud which is pointing in the direction in which it is 

 desired that growth may extend ; in most cases this will be a 

 bud pointing outwards, so that the branches may spread apart 

 from each other, though some varieties of apples are so 

 straggling in their habit that the reverse is desirable. That 

 the position of the bud influences the direction of the growth 

 arising from it is, no doubt, true, though perhaps not to such 

 an extent as is generally supposed, for it is sometimes found 

 impossible to recognise the difference between similar trees 

 which have been pruned for many years to inside or outside 



