136 First Report on Economic Zoology. 



one to three air holes - the larva? eat out secondary galleries in the 

 bast which branch out at right angles to the primary gallery ; (ii) the 

 beetles in xiugust and September bore into the pith of young pine 

 shoots at a distance of from one to three inches from their extremities, 

 eating out a tunnel up to the terminal bud. The holes where the 

 entrance is made are surrounded by a ring of opaque resin ; (iii) the 

 beetles bore into the sap wood of the root-stock of quite sound trees 

 to hibernate, and thus trees may become sickly that were formerly 

 quite sound, and so attract beetles during the following year. 



The beetles appear in April and May, and again in June and 

 July. The larv?e hatch in April and May, and pupate in June or 

 July and even August, 



Those that hatch in June may produce a second brood in August, 

 and this second brood attacks the terminal shoots and branches. The 

 whole life cycle lasts from sixty to eighty days. 



It should be remembered that the lieetles hibernate in the adult 

 stage in the root stocks and roots of standing trees, also in old 

 stumps. 



Scldich * gives the following protective and remedial measures : — 



i. Timely and frequent thinnings of woods and quick removal of 

 all sickly wood. 



ii. Clearance of felling areas by the middle of April. 



iii. Uprooting of stumps and broken trees or barking the same. 



iv. Pine woods if damaged by fire should be felled. 



V. Insect-eating mammals and birds should be protected. 



vi. All standing trees containing larva? and pupa? should be felled 

 and barked and the bark burned. 



vii. Trap trees should be felled from February to September, so as 

 to supply trees which are not too dry for the beetles to breed in. 

 These should be barked at the middle of May, and others at intervals 

 of four to six weeks, and the bark burnt. 



Of these rules the most important are ; (A) the destruction of 

 attacked trees at the proper time ; and (B) using certain unhealthy 

 trees as " trap " trees. If there are no unhealthy trees in the 

 plantation, certain of them should be made into " trap " trees by 

 ringing the worst trees. This is done by cutting strips of bark round 

 the trees in the early spring so as to produce an unhealthy state, and 

 so attract the beetles to lay their eggs and thus keep them away 

 from the surrounding ones. 



These " trap " trees should be burnt later, before the larvae and 

 pupae have matured. 



* " Manual of Forestry," Vol. IV., p. 242.. 



