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Corsican pine woods are comparatively free from injurious insects and do 

 not form centres of dispersal. The most injurious species are Hylohiiis 

 abietis, Myelophilus 'piniperda, Pityogenes hidentatus, Hylastes ater and 

 H. opacus. Some secondary enemies {e.g., Ips (Tomicus) acuminatm) 

 have in certain localities become of primary importance. 



Attention should be given in the first place to Hylobius abietis and 

 Myelophilus pi?iiperda. The survey indicates that the former can best 

 be controlled by trapping the adults, and that the latter can be con- 

 trolled by means of trap-trees. Further information with regard to 

 the best means of trapping Hylobius, and to the most suitable time for 

 setting and barking trap stems for MyelopJiilus, in difierent localities 

 is desirable. It is also a question whether Scots pine is not planted too 

 extensively, both pure and in mixture with other coniferous trees. 

 From the entomological point of view this is undoubtedly the case, and 

 statistics as to the rate of growth of timber support the contention. 



With the exception of the Douglas fir seed-fly, Megastigmus spenno- 

 trophus, there is no evidence of imported insects causing serious loss 

 to foresters in this country. 



A description of the more important forest insects is given in an 

 appendix. Of those found in felled areas, the hfe-history of Hylobius 

 abietis is not very well known. All the early stages are spent under- 

 ground in the stumps and roots of Scots pine, and, as a result, the only 

 sure remedial measure is to trap and collect the adult weevils. Pissodes 

 notatus and P. pini have a similar life-history, though their habitats 

 are usually different, P. pini preferring pole-woods and P. notatus 

 young plantations of two to ten years standing. Like Hylobius, the 

 weevils of this genus have a long adult Hfe, and are to be found through- 

 out all the warm months of the year. The life- cycle commonly 

 occupies a year. The female lays her eggs in punctmes made in the 

 bark, and the grubs tunnel between the bark and the wood, often 

 causing radiating galleries that end in the pupal chamber. 



Both species are easily trapped during the warmer months with logs 

 which should be removed and barked every three months, the bark 

 being burned. P. pini attacks Scots pine or occasiona ly spruce, and 

 any part of the tree may be injured. P. notatus attacks Scots pme, 

 and sometimes Austrian and Weymouth pine. The larva mines the 

 bark of the stem and roots, girdhng them and killing the plant. The 

 adult gnaws the young shoots. Trees weakened or injured from any 

 cause are more liable to attack. 



Myelophilus pi'niperda (pine-shoot beetle) has normally two broods- | 

 and one generation a year. The eggs are laid and the larvae burrow < 

 iu Scots pine stems. The beetles bore in the last year's shoots, and 

 severe attacks iavolving repeated loss of the leading shoot, kill the tree. 

 This beetle will become more serious if it is compelled to attack green 

 standing timber, when the feUing, which is still going on everywhere, 

 ceases. The best means of coiitrolliug it are by careful thiruiing 

 and cleaning of all pine woods. Stems felled during the winter should 

 be barked in May and the slash burned up before that date. Where 

 attacks are severe, trap-stems should be felled in September, and barked 

 in May or June to catch the first brood, and felled in July, and barked 

 in December for the. autumn brood. The lesser pine-shoot beetle, 

 M. minor, causes similar damage, but its egg-galleries, being horizontal, 

 are more injurious. It has only been observed in Scotland. 



