THE MONTHLY BULLETIN. 



227 



with black head and legs. The pupal stage is passed in the ground in 

 a thin cocoon, the pupre being yellowish in color. 



Life History.— The adults hibernate during the winter under any 

 protective covering and appear in the spring about the time the young 

 asparagus shoots are coming through the ground. The adults imme- 

 diately begin to feed upon the tender sprouts and to lay their eggs 

 upon them. The eggs hatch in about a week and the grubs begin to 

 feed upon the sprouts. The broods continue to work throughout the 

 summer eating all parts of the asparagus plants. After about two 

 weeks the larvae are ready to pupate. They then leave the plant and 

 work into the soil where pupation takes place and within eight or nine 

 days they emerge as adults. The entire life cycle requires about one 

 month but there are many overlapping generations each year. 



Distribution. — In the year 1904 the insect was reported as occurring 

 at Bouldin Island, California. In 1906 it was reported to occur in 

 great numbers at Oakley. It is now likely to be quite widely distrib- 

 uted throughout the central part of the State. 



Food Plant. — So far as known in this State the pest feeds only 

 upon asparagus, attacking principally the tender shoots but also work- 

 ing upon the rind and stems of the older seed plants. 



Control. — The control of this pest is not so difficult as it would seem 

 in view of the fact that arsenical sprays cannot be used upon the tender 

 marketable shoots because of the poisonous effects to the consumers. 



In the spring when harvesting the shoots it is advisable to leave 

 some of them for the beetles to lay their eggs upon ; cutting and burn- 

 ing these before the eggs hatch. Another practice is to keep all the 

 seedlings, except a few for traps, cut down. Upon those left the beetles 

 will collect in great numbers and may be easily killed. In the spring 

 or after they are covered with eggs the plants should be cut down and 

 burned. 



As soon as the crop is harvested the seedlings and feathery plants 

 should be thoroughly sprayed with arsenical sprays, which will serve to 

 kill many of the mature beetles before they go into winter quarters. 

 One pound of lead arsenate to sixteen gallons of water has given excel- 

 lent results. 



Dusting air-slacked lime of pyrethrum upon the larvge or spraying 

 plants infested by them with kerosene emulsion or tobacco extract are 

 exceedingly effective as the larvae are very delicate. Brushing to the 

 ground also destroys large numbers of them. Burning the rubbish in 

 the winter destroys many of the hibernating beetles. 



Natural Enemies. — The young of the ladybird beetles, Megilla macu- 

 lata and Hippodamia convergens, prey upon the young larvae. In the 

 east the spined soldier-bug {Fodisus maculiventris Say.) and the bor- 

 dered soldier-bug {Stiretrus ancliorago Fab.) as well as certain other 

 insects also feed upon the larvae. 



