DECEMBER 277 



of extraordinary delicacy in her ovipositor, slits the 

 bark of young shoots and deposits a vast number of 

 eggs, whence issue a horde of little caterpillars, grey- 

 green with round black heads. These are at their 

 busiest in July, stripping the larches of every green 

 leaf, and falling to the ground in autumn, where 

 they form cocoons and emerge in spring as perfect 

 flies. 



This pest first appeared or was first noticed in 

 England in 1904, when the Dodd wood, on Miss 

 Spedding's Mirehouse estate, consisting of larches from 

 twenty to seventy years old, was found to be thickly 

 infested with sawflies. These increased and spread 

 during the two following summers until fully 300 

 acres of woodland in this district have been ravaged, 

 and many trees fatally injured; besides which, 200 

 acres on the other side of the Derwent valley have now 

 been attacked. It is reported that this has put a stop 

 to planting European larch in the Lake district. It 

 remains to be seen whether the Japanese larch 

 (L. leptolepis) is liable to this scourge. It is to be 

 hoped that Mr. Stewart MacDougall who has made 

 a special study of the larch sawfly, will ascertain by 

 experiment next summer whether this tree will nourish 

 the insect. It is well to be warned in time, for the 

 splendid vigour of the Japanese larch has kept it 

 hitherto immune, or nearly so, from the canker fungus, 

 and many foresters are planting no other species. 



