130 TREE WOUNDS AND DISEASES 



patches here and there on the bole, and par- 

 ticularly on the under sides of the branches. 

 The infested tree soon becomes unhealthy, and 

 frequently dies off prematurely. Trees growing 

 in low-lying, heavy ground would seem to fall 

 a ready prey to this insect. Bostrichus laricis 

 is nearly allied to the former, but its devasta- 

 tions, which are, however, not very deadly, 

 are principally confined to the larch. It is 

 usually known as the " larch blight." Spray- 

 ing with Bordeaux mixture has been successful. 

 The pine shoot moths (Retinia buoliana 

 and R. turionella) would seem to be more 

 plentiful in this country than is generally 

 supposed. Quite lately, we visited a large 

 plantation of young Scotch fir, the terminal 

 buds of which were greatly injured by the 

 caterpillars of these elaborately coloured moths. 

 The moth lays its eggs at the base of the buds, 

 and into these the caterpillars enter by hollow- 

 ing out the centre, thus destroying the vitality 

 and causing them to take on a withered 

 appearance and to feel soft and empty to the 

 touch. Trees infested by this insect resemble 

 greatly, in their stunted shoots and exudation 



