380 INSECT PESTS OF FARM, GARDEN AND ORCHARD 



emerges in about a week. Thus the complete life cycle may 

 be passed in a minimum of three weeks at Washington, D. C., 

 where there are possibly four generations in a year, while farther 

 north, six or seven weeks may be required for the life cycle, and 

 there are probably only two generations. 



; The asparagus-beetles are held in check by several natural 

 agencies. Several species of ladybird-beetles feed upon the eggs, 

 while numerous soldier-bugs attack the larvae which they impale 

 on their stout beaks. The adult beetles are often killed by low 

 temperature in the winter, which doubtless limits their northern 

 spread, while the eggs and larvae are sometimes killed by the 

 intense heat of summer, which will also probably limit the south- 

 ern spread of the species. 



Control. One of the best means of control is to keep all 

 shoots cut down in the spring so as to force the beetles to lay 

 their eggs on the young shoots, which are cut for market every 

 few days before the eggs have hatched, and hence no larvae are 

 allowed to hatch. 



Another method which has proven effective is to cut down 

 all the seed stems but a few rows here and there, so that the 

 beetles will concentrate upon them, and then poison these thor- 

 oughly with arsenicals, or they may be cut down and burned 

 and other rows allowed to grow as traps. 



Air-slaked lime dusted on the plants in the morning while 

 the dew is on will destroy the soft-bodied larvae very effectively. 

 Another way to destroy the larvae in hot weather is simply to 

 brush them from the plants so that they will drop on the hot 

 soil. As they crawl but slowly few will regain the plants, par- 

 ticularly if the brushing be followed with a cultivator. 



Probably the most effective means of controlling this pest, 

 which was formerly a very difficult one to combat, is spraying 

 with arsenate of lead. Use 3 pounds to 50 gallons, to which 3 

 pounds of resin soap should be added to render it more adhesive, 

 although good results have been secured without the sticker. 

 Such spraying should be given as soon as cutting is over and should 

 be repeated once or twice at intervals of ten days. Where the 

 young shoots are kept closely cut and the bed is then sprayed, 

 there should be no trouble to control the pest, and young beds 

 should^ be kept thoroughly sprayed with arsenate of lead from 

 the time the beetles appear until danger from injury is over. 



