20 REPORT ON INJURIOUS INSECTS FOR 1906. 



larvae pupate during June, the beetles appearing at the end of June, 

 the commencement of July, or even later. The first developed often 

 produce a second brood. 



The beetles then fly to the surrounding trees and commence boring 

 into the young shoots, doing great damage. 



Hybernation takes place in tree stumps, the roots of standing 

 trees, or in the rough bark at the lower part of the trunk. 



PREVENTIVE AND REMEDIAL MEASURES. 



All timber known to be infected should be felled, barked, and 

 the bark burnt. 



Old stumps and broken stems should be taken up or barked. 



On all felled timber the bark should be removed not later than 

 the beginning of April. 



Trap-trees should be cut, and the pieces placed against the lower 

 part of standing timber ; in these pieces the beetles lay their eggs. 

 Not later than the end of May these props should be collected and 

 barked, and the bark burnt. 



EXPLANATION OF PLATE III. 



Fig. i. Piece of Pine bark showing the burrows of the Pine Beetle 



(Myelophilus piniperda, Linn.). 

 Fig. 2. Imago. 

 Fig. 3. Larva. 

 Fig. 4.-^Pupa. 



THE ASH BARK BEETLE. 

 Hylesinus fraxini, Pz. 



Three cases of damage to Ash trees have been reported upon. In 

 all three the trees were perfectly sound otherwise. 



The female beetle lays her eggs on the stems and branches about 

 the end of April, and the larvae hatch out in about twenty-eight days, 

 becoming full-fed and pupating towards the end of June, and remain 

 in the burrows in the bark until the following April. 



The mother and larval galleries, and pupal chambers are well 

 illustrated in Figure I, PI. IV. 



PREVENTIVE AND REMEDIAL MEASURES. 



On young Ash trees, spraying with a mixture of carbolic acid and 

 75 per cent, alcohol gave very good results. 



Trees badly attacked should be barked in June, and the bark 

 burnt. 



Tarring the trees has been tried, but with only partial success. 



