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Cabbage Fly. The Flies are common in April and ]\Iay 

 laying their eggs on the necks of onions or on the leaves 

 just above the soil surface. After about a week, the eggs 

 hatch into larvae which becomxC fully grown in three to four 

 weeks, and are then about |in. long. They turn to brown 

 pupae 111 the soil, though a few m^ay remain in the bulbs, 

 and the Flies commence to appear about fourteen days 

 later. There are several broods in the year though the 

 exact number has not been determined ; the winter is 

 passed as pupee which give rise to the early Flies of the 

 next year. In the earliest indications of an attack the first 

 leaves become yellow and then whitish, followed by other 

 leaves behaving in a similar manner. Very young plants 

 are usually nearly eaten through just above the forming 

 bulbs, and the larvae migrate through the soil to attack 

 fresh plants. As the onions increase in size each may 

 shelter a num.ber of maggots which devour the interior 

 and render it rotten. As regards remedial measures 

 insecticides are useless against the maggots on account of 

 their burrowing habits. All infected onions should be 

 pulled up and burnt. Earthing up the young plants is 

 valuable as it protects the forming bulbs. Early sowing 

 is also to be recommended in order to get the plants well 

 started before the Flies appear ; or the seeds may be sown 

 under glass February and planted out in April. Trench- 

 ing and burying the soil containing the winter pup^ as m 

 the case of the Celery Fly, should not be neglected. 

 Various substances are also advised in order to deter the 

 females from laying their eggs, and one or other of the 

 following methods are useful. Watering, or better still, 

 spraying the bases of the plants with an emulsion consist- 

 of two to three pints of paraffin and i lb. of soft soap 

 dissolved in one gallon of boiling water. To this pour 

 seven to eight gallons of soft water. Add the paraffin 

 vvhile the soap solution is hot and churn the mixture -very 

 thoroughly by syringing it back into itself so that no free 

 paraffin remains on the surface. A mixture of one bushel 

 of soot to two of finely powdered lime is also recom- 

 mended. In America they advise a mixture of carbolic 

 acid and lime. Three pints are slaked with a gallon of 

 water and a tablespoonful of crude carbolic is added after- 

 wards. This should be well watered round the bases of 

 the plants. 



Growers of bulbs often lose many plants from the 



