74 FOREST ENTOMOLOGY. 



ation, however, takes about fifteen months for complete development. 

 The beetles swarm, or rather leave their winter quarters, about the 

 beginning of April. These old beetles, therefore, deposit eggs on 

 the roots of trees which have been felled about two or three years. 

 The larvae hatch out in about three weeks' or a month's time, and 

 feed until about May or June of the following year. They then 

 pupate for a short time, about three weeks being considered the 

 regular period, and appear as perfect beetles about June or July. The 

 late swarmers are comparatively harmless, as they soon hibernate 

 under rough grass and heather, ready to do double duty the following 

 year. The larvae commence eating just under the bark, but do not 

 reach the bottom of the bark and the surface of the wood until about 

 the end of September. Then for the remainder of their feeding-period 

 they make long winding galleries. 



It may be noted that there is a common opinion that the 

 insects lie for three years in the larval stage, and therefore it is 

 advisable to give the ground three years' rest in consequence. The 

 amount of rest is quite practicable, but I am, from personal 

 examination, of opinion that they rather prefer attacking the roots 

 that have been cut for three years, and only live for a season in 

 the larval stage. 



Preventive and Remedial Measures. 



As this is a very destructive beetle, it is advisable that, as far as 

 practicable, the insect should be kept well in check. 



As regards dealing with the beetle, the only remedy is collecting 

 and destroying. Success in this respect will greatly depend on the 

 method of local work and its associations. My own experience has 

 been in connection with cutting a portion of a large tract of pure 

 Scots pine every year with a movable sawmill in the wood, and also 

 replanting a portion of the ground annually. At first the replanting 

 was clone on the heels of the cutting, and the result was that the 

 plants were eaten off wholesale, and replanting had to be adopted. 

 In the summer season the sawdust hole was carefully examined every 

 morning and the beetles from the fresh sawdust destroyed. So much 

 for beetle destruction. Now as regards the destruction of larvse. In 

 the winter season all branches accruing from the trees felled in summer 

 were burned on the ground, and as many fires as possible made on the 



