PREVENTION AND DESTRUCTION OF INSECT PESTS. 519 



pickling onions is nearly always followed by ce.ssation of attack 

 in such insects as onion fly, especially if it is broadcasted when 

 there is dew on the leaves : at the same time it stimulates the plant 

 to growth, and makes good the damage caused by the insects. 



Infestation is often carried to gardens in dung wiid leiif-moidd: 

 these should be examined, and if found to be very foul, should be 

 mixed with gas-lime if possible, and not used until the lime has 

 done its work, and so purified the manure. I have seen many 

 gardens infested in this way. Mould-heaps and peat-heaps should 

 always have a dressing of lime on the top to keep off the daddy-long- 

 legs, click beetles, &c., that will lay their eggs there if they get the 

 chance. Lastly, every farmer and gardener should protect as far as 

 he can the numerous insects that are beneficial, and the birds and 

 animals that help to keep down our only too rapidly increasing 

 insect pests. 



The enemies of insects include such groups of insects as lady-birds, 

 lace-wing flies, hover flies, ichneumon flies, taohina flies, sand-wasps, 

 carabidee or ground beetles, &c., described in previous chapters. 



Besides insects, frogs, toads, and shrew-mice do much good in 

 gardens, where they can be usefully employed ; and numerous birds 

 are of the greatest benefit in checking insect depredations, notably 

 the family of Tits or Parid<je, and many of the migratory birds. 

 Even the thrush does good by destroying heaps of grubs, snails, 

 and slugs, and so makes up for the loss it sometimes occasions 

 amongst the fruit ; and the rook and starling kill the wireworm in 

 the fields which as yet we cannot do, and the plover takes no toll 

 and does infinite good. 



