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" In recent years the larch plantations of Great Britain have 

 been visited by a pest which has already caused great losses in 

 certain places and threatens to inflict serious injury on British Fo- 

 restry. The Large Larch Sawfly is known to have done much 

 damage in Denmark about sixty years ago, and in more recent 

 times has devastated the larch forests of North America. How 

 long it has been present in Great Britain is not known, but its 

 presence was not officially confirmed till 1906, when it was reported 

 from Cumberland. It has since been found over a large area in 

 Wales, a wide district in the north of England, and a very con- 

 siderable area of the south of Scotland. It probably exists in other 

 parts of the Kingdom. There is reason to believe that up to the 

 present the general attack is but slight, but in the spots where the 

 prevalence of the pest is greatest many thousands of trees have 

 been killed. Nor is it likely that the plague will go no further. 

 There are evident signs that it has spread in recent years, and it 

 is recorded that in the United States and in Canada it did not 

 stop till 50 to 100 per cent of the matured larch over vast areas 

 was destroyed, with the loss of many billions of feet of timber. 

 The seiious nature of this prospect has led the Board to place the 

 Sawfly among the dangerous insects scheduled under the Destruc- 

 tive Insects and Pests Order, the presence of which on any plan- 

 tation must at once be reported to the Board. The y are also en- 

 gaged on an investigation of the extent to which it prevails in this 

 country in the hope of discovering some preventive or remedial 

 measures. Every occupier of any premises on which the insect is 

 found, is bound therefore to report the discovery under a penalty 

 of ten pounds, but few cases have been reported, chiefly on account 

 of the inability of most persons engaged in forestry to identify the 

 pest, or recognise the symptoms of an attack. The Sawfly remains 

 in its larval state for only a few weeks of the year, and for some 

 part of that time it is very small and consequently, easily over- 

 looked. The appearance of an attacked tree, however, is such 

 that for a much longer period the characteristics can be distin- 

 guished by an expert. In spite, however, of this extension of time 

 it is not possible for the Board's Inspectors to examine every larch 

 plantation in Great Britain, and the Board feel it incumbent on 

 them to ask for the assistance of every person interested in fo- 

 restry in tracing the presence of the infestation. 



" The search may be conducted in two ways : 



i) The actual insect may be looked for as (i) egg embedded 



