8 FRUIT TREES AND THEIR ENEMIES 



A large number of insects which prey upon trees 

 pass a portion of their existence in the earth, the 

 cocoons or grubs being in many cases buried during 

 the winterat the depth of a few inches below the surface. 

 Tillage of the soil is one way in which much good can 

 be done in such cases, for it brings to the surface the 

 various insects, and exposes them to destruction by 

 birds. On the other hand, the growth of grass and 

 weeds under fruit trees is very injurious, for, not only 

 does it seriously interfere with the health and vigour 

 of the trees, but it also affords facilities for the 

 harbouring of many insects. For similar reasons, all 

 prunings, dead leaves and rubbish should be cleared 

 away from under the trees, and burnt, for they are 

 often infested with the eggs and cocoons of insects, as 

 well as with fungus spores. 



The direct destruction of insects by applying in- 

 secticides to the soil is a branch of the subject about 

 which little or nothing is known at present. With 

 the exception of certain proprietary articles, the only 

 substance used to any extent is carbon disulphide, 

 a very volatile and inflammable liquid, which is in- 

 jected into the soil round about the roots of the 

 trees, by means of a syringe specially adapted for 

 the purpose. 



Vermorel has lately devised an apparatus for the 

 destruction of moths and other night insects, consist- 

 ing of an acetylene flame, which gives a brilliant light, 

 surrounded by a tray holding paraffin. The moths 

 are attracted by the light, and fall into the paraflin. 

 It is known by the name of the " Meduse " lamp, and 

 is sold at i8j-. 6d. 



