FAMILY SCOLYTIDAE 517 



Owing to the more or less isolated nature of the chilgoza forests in 

 Zhob, it should prove quite possible to stamp out 



Protection and incipient attacks of this beetle and its companion the 

 Remedial Measures. Phloeosinns as soon as they appear, and to prevent their 



spreading to adjacent areas. The severe attack experi- 

 enced in the Shinghur Forest and neighbouring areas took place in what was 

 a virgin forest untended till then by man. The destructive method of collect- 

 ing the cones from the tree by breaking off the branches to get at them, 

 combined with a succession of hot dry years, doubtless led to the great 

 increase in the number of beetles present in the forest. At Shinghur the 

 trees do not stand densely on the area, and the open nature of the forest 

 is probably due to a number of them having been killed out by the beetles. 

 A possible reason for this state of affairs is to be found in the fact that the 

 chilgoza seed has been collected with more regularity since the British have 

 been in the country, and that this more intense collection has resulted in a 

 greater number of men frequenting the forest, and in a greater amount of 

 damage being done to the trees in consequence, thus providing the beetles 

 with a larger supply of easily-got-at food material. Grazing and its con- 

 comitant damage has also certainly been more intense than was the case 

 when the forest first began to occupy the area. In considering measures for 

 endeavouring to stamp out the pests, or for reducing their numbers to a 

 point at which they will no longer be harmful, it will therefore be needful to 

 remember that the forest must be treated as a whole, and the entire area 

 carefully taken in hand and worked over. 



We have seen that the signs of attack are easily observable on the 

 outside of the trees in round shot-holes usually surrounded by a ring of resin 

 to which wood-dust may be sticking, and in pear-shaped blobs of turpentine 

 or long trickles of this substance being present beneath the shot-holes 

 (cf. pi. xli). 



The methods of dealing with such attacks are detailed in chap, iv, p. 46. 



It should be most carefully borne in mind that the very greatest circum- 

 spection must be used in 



(a) Selecting the trees for felling. 



(b) Felling them at the right time. 



The reasons for (a) are obvious, since the tree is valuable on account of 

 its seed and not for its limber, and therefore produces an annual income 

 which ceases when the tree is felled. It is essential that the infested 

 trees should be removed; because, beyond the fact that they themselves 

 will die under the beetle's attack, other trees will become subsequently 

 infested from the insects they breed, and will be killed in their turn. 

 (b) The felling at the right moment is necessary, because otherwise the 

 benefits to be obtained (i.e. the large number of insects destroyed, and the 

 consequent diminution in the number available to do further damage in the 

 forest) will be lost. Whilst, therefore, a careless selection of the trees to be 



