82 



Thk Canadian Hokticui.iukist. 



for another generation. The winter is passed in the |»upa state, and the flies 

 emerge in the early part of June or about the time thai the young onions are 

 sufficiently grown to furnish food for the young maggots (Fig. 28). 

 The following preventives and remedies have been suggested : 

 Instead of sowing onion seed in rows where the ycjung seedlings grow in 

 contait. or nearly so. giving every facility for passing from one to another, they 

 should be grown in hills, so that* the larv;e cannot make their way from one hill 

 to the other. 



Scattering tlry unleache.d wood ashes over the beds as soon as the plants are 

 up, while they are wet with dew, and continuing this as often as once a week 

 through the month of June, is said to i)revent the deposit of eggs on the plants- 

 Planting the onions in a new |)lace as remote as possible from where they 

 Were grown the jjrevious year, has. been found useful, as the Hies are ncjt supposed 

 to migrate very far. 



I'ulverized gas-lime scattered along between the rows has been found useful 

 in keeping the flies away. 



Watering with the licjuid from pig-pens, col- 

 '\ lected in a tank provided for the purpose, was 

 found by Miss Ormerod to be a better i)reven- 

 tive than the gas-lime. It is recommended to 

 run a njller over the ground a few times after 

 the seed has been sown, thus compacting the 

 soil so that the maggots cannot make their 

 way through it from one plant to another. 



Water raisetl nearly to the boiling point and 



poured along the rows from a tea-kettle or other 



convenient vessel, has proved destructive to the 



maggots without injury to the ))lanls. The water should be ap|)lied so as to 



go directly to the bulbs and not to tiie leaves. 



Most excellent results have been obtained in I">ngland by growing onions in 

 trenches, and as the bulbs grew, the earth was worked down upon them so as to 

 keep them buried throughout the season. The onion bulbs should be (overed 

 with earth u[) to the neck, or even higher, so that the fly cannot get at theni to 

 lay her eggs. 



When the onions have been attacked, and show it b\' wilting and changing 

 color, they should either be taken up with a trowel and burned, or else a little 

 dilute carbolic acid or kerosene oil sIkhiM be dropped on the infested plants, to 

 run down arotmrl iheni and tlestrox tli. ui.iggots in the root and in the soil 

 around tlu ni. 



Via. -is. 



TlIK I'tKKKCT InsKCI 

 (IK Fl.Y. 



