Bee. 1894.] 



INJURIOUS INSECTS AND FUNGI. 



211 



Modes of Prevention and Remedies. 



As many of the pupae are in the earth, it is most essential, 

 when the celery crop has been taken from the trenches, that the 

 earth should be levelled carefully and dug deeply, and the upper 

 surface put well underneath to prevent the flies from com ng up. 

 This should be done in the same way with infested pat snips. 

 A good dressing of lime, or of lime ashes, or of gas lime, might be 

 applied with advantage. Every particle of foliage and stem must 

 be deeply buried, or it is better that these should be collected and 

 burnt directly the celery or parsnips have been dug. If the 

 leaves are merely placed in lumps, or upon composts, or mixens, 

 not in active fermentation, it is very probable that pup9B may 

 be carried out with manure for celery or parsnips. This pest 

 will not be stamped out unless celery and parsnip growers are 

 most particular in destroying the leaves of infested r lants. 

 Thistles should be eradicated. Meigen says it is occasionally 

 found on thistles, and Macquart states that it infests them in 

 France and Germany. 



In gardens, or where only a few rows of celery or parsnips 

 are grown, it is possible to check the attack, at all events to 

 some extent, by pinching the infested leaves to kill the larvae 

 in them. But where celery and parsnips are largely cultivated 

 this remedy would be out of the question. 



It is desirable to force rapid leaf growth where there is a bad 

 attack. Nitrate of soda mixed with a little agricultural salt 

 will effect this. 



Soot or finely powdered lime scattered over the plants when 

 the dew is on them is likely to prevent the flies fr an laving 

 eggs upon the leaves. A mixture of one bushel of lime to three 

 bushels of soot has been found very useful, put on when n^in or 

 dew is upon the leaves. 



Spraying with various substances has been found most 

 beneficial. A mixture of paraffin and soft soap and water at 

 the rate of a pint of paraffin and 8 oz. of soft soap to 10 gallons 

 of water has been found eff*ectual, put on with a knapsack 

 machine. The extract of 12 ozs. of quassia chips and 8 ozs. of 

 soft soap to 10 gallons of water proved serviceable. The spraying 

 was done twice. 



Celery Stem Fly (Piophila apii, Westwood). 



This fly, though not so well known as the other eel er r fly, 

 Tephritis onopordtnis, sometimes does even more harm to the 

 celery crop. In the present season, 1894, it has seriously injured 

 the celery in many localities. 



The larva (Fig. 1) of this fly bores into the stems, or pe- 

 tioles, of the celery from the point where the earth is ba^ked- 

 up to bleach them, down to the bulbous end. In steiiv^, or 

 petioles, examined, the passage of the larva was traced some- 

 times in the tissues to the middle of the stems, then rarn- 

 ing to the outside, and again towards the middle to the extreme 

 lower part. Here and there, large holes were seen caused by 



