i62 FAMILY BOSTRYCHIDAE 



trees, if badly infested, should be cut down at about the end of 

 May (when they will contain larvae and pupae) and be chopped 

 up and burnt. To ascertain the time to fell the tree, cut out a 

 strip of bark and see if the sapwood contains small white grubs 

 or pupae. If so, this is the time to remove the tree. If it 

 is left longer the larvae and pupae will change into beetles, and 

 these will then bore their way out and leave the tree and attack 

 fresh ones. This careful watch should be kept up between April 

 and October for a year or two after the plan of immediately 

 removing from the forest the cut fuel and logs has been adopted. 

 {b) To save green sickly trees from being promiscuously attacked, 

 "trap" trees should be used. Suitable trees are selected in 

 convenient places adjacent to the areas in which fellings have 

 just been made, and are ringed or felled about February. The 

 April beetles will lay their eggs in these trees in preference to 

 attacking green ones. The trees should be felled in May, cut up, 

 and burnt. In June another set of trees should be similarly 

 prepared to catch the second generation of beetles, this second lot 

 being cut down and burnt about the end of August. 



Careful watching will show whether it is necessary to repeat this treat- 

 ment the next year. 



During my visit to Changa Manga in May 1905 I found that these 

 recommendations had been given effect to in some measure. The removal 

 of the wood was commenced soon after the felling ceased in March, the 

 whole of it being carried to the depot in from two to three months. The 

 old unsold wood in the depot was auctioned off annually. 



These suggestions which were drawn up for Changa Manga apply 

 equally to other parts of the country, the only difference being that 

 the beetles appear earlier in the year and remain later, their ovipositing 

 months consequently being to some extent different from those of the north 

 of India. 



Where possible, fresh-cut poles should be kept under water whilst 

 the chemical changes in them during the process of drying are taking 

 place. Or, where such treatment will not injure their utilization, they should 

 be soaked in crude Rangoon oil as already described for bamboos on p. 136. 

 So long as S. crassum was known simply as a wood-borer the damage 

 done by it was looked upon as affecting only the commercial value of the 

 tree. The discovery that it tunnels into the young green shoots of sal (and 

 possibly other) trees and the tops of saplings alters the position of the insect 

 as a pest. It becomes obvious that a first necessity is cleanliness, and that 

 in so far as is possible all felled material must be removed from the forest. In 

 sal coppice areas this should be laid down as a rule from which no deviation 

 is permissible, all the refuse from "tops " etc. of fellings being burnt. If an 

 area is seen to have the leaders of saplings and twigs badly attacked by the 



