GARDEJS INSECTS. 63 



the poisonous compound within its leaves and kill those 

 who afterwards ate the plant. Pyrethrum has been 

 found excellent as a destroyer, but probably Hammond's 

 slug shot is as effective. Sometimes good results follow 

 the application of white hellebore mixed with land plas- 

 ter, four parts to one. In other cases a solution of one 

 quart of powdered alum to twelve quarts of boiling 

 water is effective. Sometimes good effects result from 

 an application of a tablespoonful of pyrethrum mixed in 

 tw^o gallons of w^ater, and applied forcibly with a spray 

 syringe. The writer's experience with the cabbage worm 

 dates from the period of its southern raid from Canada, 

 where it was first established as an emigrant from 

 Euroi:)e. He has had annoyance from it in variable 

 degrees every year, but never to that serious extent as 

 reported from localities where it has occasionally de- 

 stroyed entire crops of cabbage. 



Cabbage Louse. — The Downy cabbage louse is a 

 mealy, soft-bodied insect, sometimes appearing in thou- 

 sands, swarming like bees upon the leaves of young cab- 

 bage, Brussels sprouts and cauliflower. It can be driven 

 off by ai)plication of Hammond's slug shot. Personal 

 experience should always enable one to express opinions 

 on a subject, and the writer, having had years of com- 

 bat with this ph;nt louse, looks upon it as a pest to be 

 dreaded, difficult to kill, and destructive in its work. 

 He has seen, upon the seed farm of his firm, as much 

 as one hundred and fifty acres of otherwise healthy tur- 

 nip plants, and one hundred acres of cabbage in the 

 seed producing condition, entirely destroyed within 

 three weeks. It is especially fond of the tender seed 

 stems of the ruta baga, and in nearly all seed-growing 

 districts where ruta baga seed-growing has been pursued 

 twenty years, the cultivation has ceased entirely on ac- 

 count of the great increase of this insect. On young tur- 

 nips the louse can be destroyed by dusting witii ParivS 



