PEAR-BORER. 



3 



and when pruned they must be immediately burnt up ; the remaining 

 branches must be carefully searched for. The eggs are always placed 

 near the hybernating nest of the pear leaf roller Bhodopluea hollandella, 

 Rag. Kerosene emulsion is very beneficial after pruning as well as in 

 early June, namely the time of larvae hatching, for it kills at the same 

 time the larvae of the leafroller. After they bore into the fruit, no 

 remedy is accessible, except carbon bisulphide, but this chemical being 

 very expensive I only used it on a dwarf tree, pouring it with a small 

 brush into the hole, through which insect entered ; it very soon kills 

 the insect and no injury was done to the fruit. Benzole also has the 

 same effect, but inferior, and little injures the fruits. Now in our 

 College garden, picking of the injured fruits by hands is the only means 

 resorted to, as they are easily recognizable by their black holes and 

 brown excrements. Lamp is of no use. 



Entomological Laboratory, 

 Agricultural College, Sapporo. 

 Jan. 5th. 1897. 



Printed April 30, 1897. 



