46 FOREST ENTOMOLOGY. 



The above account of the life-history may be only taken as regards 

 England, or perhaps the- north of France, as in Germany the cycle 

 period is shorter in the south than in the north, thus showing that 

 heat or geographical position is an important factor in life-histories. 



Preventive and Remedial Measures. 



This insect is injurious both in the perfect and larval stages, hut more 

 especially in the latter, and it is obvious that some remedial measures 

 should be given. At the same time, it may be remembered that as 

 this insect is so common and injurious in certain parts of the country, 

 many practical men, according to local circumstances, have adopted 

 their own respective methods of prevention and remedies. A few 

 hints, however, may be given. 



As regards the injuries done by the perfect beetle, they are of course 

 entirely confined to the foliage, and the only remedial measures which 

 could be adopted with any degree of success would be to place sheets 

 under the most likely resting-places or feeding-ground of the beetles, 

 and then to beat them on to the sheets, collect, and destroy them. 



The larvae, however, are much more difficult to deal with, and 

 as they live for three years in the larval stage, it is highly essen- 

 tial that some practical methods should be adopted to lessen their 

 attacks. From a forestry point of view, we have therefore to deal 

 with them either in the young plantation or in the nursery. It is, of 

 course, more difficult to deal with them in the former. In this case, 

 before we can suggest any remedial measures, perhaps the most practi- 

 cal or effective way is to remember the nature of their life-history. It 

 must be borne in mind that the female beetle prefers depositing her eggs 

 on a grassy surface, as, for example, on an old pasture-field. If, there- 

 fore, it were practical to keep the young wood comparatively free from 

 grass, it would obviously lessen the attacks, inasmuch as the females 

 would not select the surface of the young Avoods for egg-deposition. 

 How far this could be carried out would depend largely upon local 

 circumstances or conditions. If, for example, it were possible to have 

 either a clean surface or, say, to cultivate potatoes between the plants, 

 we should do much to lessen the attack, and at the same time be 

 adopting a method which, in the case of portions of land planted for 

 rapid landscape eff"ect, would perhaps be the best means to adopt. 



As regards the nursery from an estate point of view, we must 



