INSECTS INJURIOUS TO BEETS AND SPINACH 337 



in late June and early July in Illinois, and enter the earth to 

 pupate, the beetles of the next generation emerging about a 

 month after the eggs were deposited. The beetles of the second 

 generation lay their eggs from July to September and the beetles 

 mature before winter sets in. In the District of Columbia, 

 Chittenden observes that the first generation is more abun- 

 dant on chickweed and the second is injurious to beets and 

 spinach. 



Control. Thoroughly dusting or spraying the plants with 

 Paris green or preferably arsenate of lead will readily destroy 

 the larvae and probably most of the beetles. As in combating 

 all flea-beetles the destruction of the weeds upon which they 

 multiply is important. 



The Larger Beet Leaf -bee tie * 



One of the principal pests of the sugar-beet in Colorado and 

 adjacent States is a rather large brownish leaf-beetle which with 

 its larvae destroy the foliage or so injure it that the plant dies. 

 It is often locally known as the " alkali bug " from the fact the 

 injury is mostly on alkali soil or land near it, and " french bug/' 

 probably from the " frenching " of the foliage. The beetle is 

 from one-quarter to one-third inch long, and rather resembles 

 the elm leaf-beetle, varying from pale yellow to black, with the 

 wing-covers striped as shown in Fig. 242. Several wild plants, 

 including blites, Russian thistle, and saltbush f probably furnish 

 the normal food of the insect. 



" The beetles are gregarious, ' sometimes occurring in swarms 

 like blister-beetles.' Their brownish-gray eggs are deposited 

 in irregular masses, usually on the under sides of the leaves. 

 They hatch in about six days, and their larvae or young commence 

 feeding at once, continuing for nine or ten days, when they dig 

 their way into the ground, a few days later coming forth as beetles. 

 Although the beetles do much injury, the principal damage is 

 sometimes accomplished by the larvae, hundreds being found 



* Mdnoxia pvncticollis Say. Family Chrysomelidce. 

 f Dondia americana and D. depressa, Scdsola tragus, and Atriplex argentea. 



