INSECTS AND DISEASES INJURIOUS TO FOREST TREES. 



coloured moth. The moth lays its eggs at the base of the 

 buds, and into these the caterpillars enter by hollowing out 

 the centre, thus destroying the vitality and causing them to 

 take on a withered appearance and to feel soft and empty to 

 the touch. Trees infested by this insect resemble greatly in 

 their stunted shoots and exudation of resin such as have 

 become a prey of the Pine beetle (Mytlophilus piniperda) only 

 in the latter case it is the fresh young shoot and not the 

 bud that is attacked. The Eetinia would seem, from all my 

 notes and observations, to be most abundant in what might 

 be termed neglected fir plantations, that is, where the trees 

 have suffered from overcrowding, and if growing under 

 unfavourable conditions as to soil, etc., and particularly 

 when the wood is composed entirely of one species. There 

 is no method of dealing with large infested areas, for the 

 attacked trees have repeatedly been cut over and removed 

 without any seeming diminution in the numbers of the 

 insect. One experiment with a small infested corner has 

 been rewarded with good results, by lighting a fire to wind- 

 ward, and causing the smoke of coal tar to pass over. This 

 might be worth trying in the case of fruit trees infested by 

 particular insects. 



The Larch Miner. (Coleophora laricella.) Few, other 

 than those specially interested in tree diseases, have the 

 remotest idea that the yellow, withered appearance of many 

 of our English larch plantations is due to the larvae of the 

 above tiny moth. It usually attacks young trees, say, from 

 five to twenty years old, and although it may not kill them 

 out, yet the repeated onslaughts year after year tend to 

 keep the trees in an unhealthy condition, and so render 

 them liable to other and more deadly diseases. 



Unfortunately the attacks of the larch miner are by no 

 means confined, as is usually supposed, to trees growing 

 under unfavourable conditions, for I have this season noticed 

 in an unusually healthy, fast-growing plantation in Sussex 

 that almost every tree was more or less affected. Certainly 

 in another large extent of larch in Gloucestershire which I 

 examined a few days ago, and where nine-tenths of the trees 

 were being ruined by the Peziza, the larch miner was very 



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