268 SCHOOL ENTOMOLOGY 



crops, such as cotton, corn and tobacco, on which it is expen- 

 sive to use other means. Poisoned bran mash (see page 329), 

 is an effective remedy for cutworms, particularly in gardens. 

 It should be applied a few days before the plants are set or 

 before the seed plants appear. Sow the mash broadcast late 

 in the afternoon so that it will be moist when the worms feed 

 at dusk. Keep poultry away from fields so treated. Clover 

 which has been dipped in water containing one-third pound 

 of Paris green per barrel may be used in the same way, par- 

 ticularly along borders of fields next to grass. Market gar- 

 deners commonly protect plants by means of tin cans from 

 which the bottoms have been removed or by paper cylinders, 

 which are sunk into the soil around the plants. Garden 

 plants may sometimes be protected from cutworms by dip- 

 ping in arsenate of lead, three pounds to the barrel, when 

 setting them, as advised for flea beetles. 



146. Plant Lice or Aphides. Almost every garden crop 

 is attacked by one or more species of plant lice, which mul- 

 tiply so rapidly that if they are not promptly controlled 

 serious injury results. 



Cabbage Aphis * (44). Cabbage, turnips and other 

 cruciferous garden crops are frequently found covered with 

 disgusting gray, waxy masses of cabbage aphides. The eggs 

 of this species are laid on cabbage during October and 

 November and, in central New York, hatch the next April. 

 Herrick and Hungate observed twenty-one generations 

 from early April until December. During the summer the 

 wingless females become full grown in about two weeks 

 and live for about forty-six days, during which time they 

 will give birth to about forty young. Generations of 

 winged females appear, particularly on crowded plants, and 

 spread the pest. They live only about ten days and bear 

 * Aphis brassicce Linn. Family Aphididce, see page 66. 



