CONTEOL OF GARDEN DISEASES AND INSECTS. 



35 



more easily killed than the harder and hardier adults. The plumber's 

 torch is effective for this pest, destroying all the insects with which 

 the flame comes in contact, after which the plants revive and grow 

 well. The torch is more safely applied to the late fall crop. It 

 is apt to injure the earlier, spring crop. These torches are not 

 practical against many other insects, and their use should be re- 

 stricted to this species and a few others. Other remedies are (1) 

 clean culture, especially in the fall, (2) trap crops of mustard or 

 other crops in the spring, and (3) hand picking of adults and eggs 

 early in the season. The systematic destruction of this insect by 

 means of a trap-crop method, i. e., planting early cole crops to attract 

 the insects before the main crop is on and then destroying the insects 

 by burning them, with the other methods advised, will help ma- 

 terially to keep this pest 

 from doing much dam- 

 age. Especially it is ad- 

 visable to kill off the first 

 and the last broods and 

 to try to prevent the in- 

 sect from gaining a foot- 

 hold in the North. 



PLANT-LICE. 



Plant-lice of three spe- 

 cies, known commonly as 



the cabbage aphis, turnip Fig. 39.— The spinach aphis (Mi/zus persicae) : a. 

 aphis, and spinach aphis ^"'"^l^ adult aphis; i young nymph: c older 

 f ^ A i:' nymph ; d, last stage of nymph, or pupa. Greatly 



(fig. 39), do much dam- enlarged, 



age to cabbage in sdme 



seasons, but fortunately, although generally distributed, they are not 

 injurious in all years in all localities. These insects so closely re- 

 semble one another that a description hardly would appeal to the 

 grower who maintains a vegetable garden as a side issue. They ap- 

 pear early in the spring and sometimes remain as late as December. 



Control. — The best remedy is nicotine sulphate (see p. 10). Kero- 

 sene emulsion and soaps, especially fish-oil soap, also are valuable, 

 and a strong stream of water frequently directed upon the plants 

 from a syringe, garden hose, or sprayer is often of service in checking 

 these pests. The early application of remedies is advisable. Clean 

 culture, as for the harlequin ciibbage bug and other insects affecting 

 cole crops, should also be practiced. 



FLEA-BEETLES. 



Several forms of flea-beetles attack young cole crops, generally 

 preferring cabbage, some of them being striped and others plain 



