DAMAGE CAUSED BY ANIMALS. 155 



With the same object in view, an alternation of the fall in different 

 localities, in place of having the annual crops following each other 

 contiguously, is also highly recommendable ; and the longer the 

 period elapsing between the planting up of each two contiguous 

 falls, so much the better. And, at the same time, it must be 

 pointed out that, by natural reproduction under present standards, 

 or by the formation of mixed crops, instead of total clearance with 

 artificial regeneration, chiefly by means of planting, we have the 

 means of obviating attacks to a considerable degree, or at any rate 

 of very materially diminishing their severity. 



In the conduct of annihilative or exterminative measures, the 

 main object must be to get hold of the beetle if possible in its 

 breeding-places, that is to say, in the fresh clearances of the 

 previous year. This can best be arranged for by digging narrow 

 trenches round the recent falls in early spring, in order to intercept 

 the beetles coming crawling from their winter quarters to lay their 

 ova in the new stumps. For this purpose the trenches should be 

 about one foot deep, and with smoothly cut perpendicular walls, 

 with holes also a foot in depth dug here and there along the base, 

 to serve as pitfalls or traps. But as, at the same time, many 

 beetles can reach the area in flight, these trenches are even more 

 useful during the summer of the second year, by hindering the 

 newly-developed beetles from crawling away from the area : the 

 trenches should be examined every day, the beetles being collected 

 together and destroyed. 



And on the newly-cleared areas themselves, and places already 

 infested with the insects, endeavours should also be made to attract 

 the beetles to decoy-objects. Such include pieces of bark recently 

 stripped from Spruce or Pine stems, laid so as to have the cambial 

 layer next to the ground, and held down in position by being 

 weighted with a stone, and also faggots about 3 or 3 J feet long, cut 

 from recently-felled Spruce or Pine poles, from which a strip of 

 bark about lj to 2 inches broad has been peeled off lengthways, and 

 which are then laid on the ground with the barked part lowermost 

 and touching the soil. Attracted by the fresh resinous odour, the 

 beetles come to these decoys, attack the cambial layer, and as they 

 take a fairly good hold of it, they can easily be collected daily. 

 By spreading bundles of fresh Pine branches on the areas cleared, 

 the beetles can also be induced to feed on them, and can then be 

 collected by being shaken or tapped out on to sheets spread on 



