CELERY FLY 225 



thus affected, the Celery is serious crippled, sometimes 

 ruined, as the stalks cannot, for lack of the elaborat- 

 ing functions of the leaves, grow and fill out properly. 

 Besides, the affected parts decay, contaminating the 

 stems, the blanched ones not uncommonly having rusty 

 marks, due to the passage of Celery Fly larvae down 

 the stem, more or less spoiling the appearance and 

 flavour, and often associated with Celery- stem Fly 

 larvae and causing the Celery to rust. 



Parsnips are also attacked by Tephritis onopor- 

 dinis, the leaves of the plants being much injured in 

 some seasons by the larvae, and the roots of the plants 

 affected are small in proportion to the damage done 

 to the foliage. 



Prevention. i. In the early stages of infection 

 the attack may be checked in gardens by pinching 

 the white spots or blotches on the leaves between the 

 finger and thumb so as to kill the larvae in them. The 

 plants must be kept under close observation, even 

 from the earliest stages, as the fly appears in April 

 and maggots have been found in the leaves of Celery 

 as late as the beginning of December. Pinching must 

 be done carefully, so as to damage the leaves as little 

 as possible. 



2. Dusting the leaves with a mixture of finely 

 powdered lime and soot in the proportion of one 

 bushel of lime to three bushels of soot has been found 

 efficacious, if put on when the leaves are damp from 

 dew or rain. It prevents the flies from laying eggs 

 upon the leaves, and prevents other pests infesting 



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