BUREAU OF ENTOMOLOGY. 257 



coast has been conducted. The infested localities have been mapped 

 and a campaign has been begun to spread a knowledge of the im- 

 portance of control measures. 

 Other potato insects have been studied in Wisconsin and Iowa. 



INSECTS AFFECTING GROWING BEANS AND PEAS. 



The bean ladybird has recurred in numbers in Colorado and New 

 Mexico. Experiments have shown that it can' be controlled with 

 lead arsenate and zinc arsenite sprays. 



The enormous plantings of beans in southern California, owing to 

 war conditions, resulted in serious injury to the crop from the corn 

 earworm, and investigations of this insect under these conditions 

 have been made. The tremendous spread of this crop resulted in 

 the great multiplication of the insect, and with the reduction of the 

 bean acreage this season serious danu\ge will very likely result from 

 the abundance of the pest. 



The pea moth, an imported pest already well established in Can- 

 ada, has made its appearance in injurious numbers in AVisconsin, 

 where it seems to be greatly increasing in number, necessitating ad- 

 ditional investigations of its life history in order that a sound 

 remedy may be established. 



INSECTS INJURIOUS TO CABBAGE AND ALLIED PLANTS. 



An investigation of the western cabbage flea-beetle, a pest of much 

 importance in the Western States, has been completed, and the 

 results are available for innnediate publication. 



The harlequin cabbage bug, after one of the periods of inactivity 

 in the North which have several times been noted, is likely now to 

 reinfest its northern range at any time, and an emergency bulletin 

 on methods of control has been prepared. 



An imported horse-radish pest, hitherto known as injurious only 

 in Canada, has made its appearance in destructive numbers in Vir- 

 ginia, and is being studied. It will live on other crucifers, and if not 

 controlled may become a pest of much importance. 



SUGAR BEET INSECTS. 



Work on the sugar beet leafhopper, which is the cause of the 

 malady known as "curly-top," was terminated at Spreckles, Calif., 

 and the station was removed to Riverside that the study of certain 

 }K)ints in the life history of the insect and the relation of tempera- 

 ture and humidity to its development might be completed. A con- 

 siderable percentage of parasitism has been observed during the 

 vear. 



OTHER TRUCK CROP INSECTS. 



Much good work was done with a number of other insects, includ- 

 ing the onion thrips and the onion maggots, the melon aphis, several 

 strawberry insects, and others. A notably good result was obtained 

 in the case of the celery leaf -tier, since it was demonstrated that it 

 could successfully be controlled by spraying with arsenate of lead 

 at the rate of 1 pound to 50 gallons of water, the first spray to be 

 made when the eggs are hatching and repeated every two weeks as 

 long as the " worms " are to be &und. This was accomplished at a 

 cost, for labor and material, of $2.35 per acre. 



