2cb FAMILY BUPRESTIDAE 



apparently rapidly decays and falls off, or more often is pecked off by wood- 

 peckers to get at the grubs beneath, and thus an attacked tree shows at the 

 spots infested irregular-shaped areas of the whitish-yellow sapwood. This 

 feature is very often present in the case of saplings and young poles, and 

 enables attacked trees to be readily recognized. 



For some years past the larva of this beetle has been known to infest 

 deodar. I took it in deodar-trees in Bashahr towards the end of June 

 1901, in newly felled trees at Pajidhar in the third week in June in 1902 

 (the grubs being from a day or two to a fortnight old only), and again in 

 November 1906 in the tops of converted green trees felled in that year near 

 Konain in Jaunsar. 



In 1908 a bark-beetle attack started in the Simla Water Supply 

 Catchment Area, and investigation showed that this insect was also present. 



During the years 1908-9 it was proved, with the help of Mr. V. Munro 

 and Pandit Gokal Dass, that this Sphenoptera passes through only one genera- 

 tion in the year. The mature beetles leave the trees during June, pair, and 

 the female lays her eggs in the bark of any newly felled unbarked trees she 

 can find or in standing sickly trees, in snow breaks and wind-thrown trees. 



The young larvae hatch out from the egg in about a week, and at once 

 eat their way down to the bast and gnaw out little irregular-shaped patches 

 in the latter (fig. 135). The grubs on increasing in size go down deeper 

 and groove both the bast and sapwood. It is probable that in some 

 cases the grubs become full-fed in the autumn, and change into pupae 

 in late October or November in the small pupal chambers eaten down 

 into the sapwood by the grubs. The winter is then passed through 

 here either as a pupa or immature beetle. 



Probably many of the grubs who pass the winter in the bast owing 

 to their not having attained full growth, and consequently not having 

 tunnelled down into the sapwood to prepare the pupal chamber, perish in 

 severe cold winters. 



This is not the case in open dry ones, as was proved in the Simla 

 Catchment Area in 1908, when immature living grubs were found in the 

 trees at the beginning of April. 



The damage committed by this insect when numerous in a forest is 



very serious. The young larvae require absolutely fresh 



Damage Committed i , ,, r ,, r , , . , . 



in the Forest. green bast, and therefore the eggs are very often laid in 



green, and apparently green standing, trees. 



The irregular method of feeding of the grubs renders the insect more 

 destructive than would ordinarily be the case, as they girdle a tree much 

 more rapidly, even when but a moderate number of insects are present, than 

 is ordinarily the case with bark-borers. Instances have been seen where 

 trees attacked at the base only have been ringed by a comparatively few 

 larvae and so killed. Within the limits defined by their several life 

 histories, bark-borers of the Scolytus type go into a tree anywhere, and thus 

 require to be unusually abundant before their operations ring and kill a tree. 



