234 



PROTECTION AGAINST INSECTS. 



Fig. 97. Cocoons 

 of P. notatus, 

 Fabr., on the 

 stem of a young 

 pine. In the 

 portion covered 

 with bark a 

 square aperture 

 has been cut, 

 under which is 

 a flight-hole. 

 (Natural size.) 



Fig. 98. Pine- 

 cone from which 

 P.notattiSj'Fabr., 

 has been bred. 

 (Natural size.) 



where P. notatns is almost confined to the 

 conifer woods of Scotland. 



c. Relations to the Forest. 



The beetle in May or June pierces the 

 bark of Scots and black pines, more rarely 

 that of the Weymouth pine, spruce or larch, 

 near the rootstock down to the bark and sap- 

 wood, partly to feed on the sap, and partly to 

 lay its eggs there. It prefers 4- to 8-year-old 

 plants, but also attacks poles up to 30 years 

 of age. The perforations resemble fine needle 

 holes, and are very numerous. 



The larvae eat their way between the wood 

 and bark in descending, slightly winding, and 

 constantly broadening passages, which become 

 filled with wood-dust ; at the extremity of the 

 burrows they construct oval cocoons made of 

 wood-fibres, out of which the beetle bores its 

 way. 



The insect is more destructive in the larval 

 stage. Plants which are attacked may be 

 recognised in July by small drops of turpen- 

 tine on the bark, and by the reddening and 

 eventual death of the needles. If it has not 

 been girdled, a few green twigs may still be 

 noticed on the wilting plant. 



The larvae also live in the younger cones, 

 often two or three together. Later on these 

 cones become yellowish-grey, and may be 

 recognised by the circular exit hole of the 

 beetle, which is about the size of No. 6 or 

 No. 7 shot. 



d. Protective Rules. 



i. All sickly plants and dominated stems 

 should be removed. 



ii. All rootstocks should be ' grubbed up, 

 and all felling areas rapidly cleared. 



iii. Woodpeckers should be preserved. 



