1910 ENTOMOLOGICAL SOCIETY. 71 



difficult matter to decide sometimes whether it is advantageous to poison the 

 adults, for if this is done there will be no larvge to devour grasshopper eggs. 



Should the adults become sufficiently injurious to warrant action, applications 

 of Paris Green or arsenate of lead will readily kill them. On account of the 

 abundance of grasshoppers this year, we may expect a large number of blister beetles 

 next year. 



Wireworms and White Grubs. 



Among the list of injurious insects of farm crops, none perhaps surpass 

 Wireworms and White Grubs, in the amount of damage inflicted. They work 

 away unseen underneath the soil, and on this account are unknown to the casual 

 observer. They are peculiarly the enemies of the careless farmer, and their pres- 

 <^nce indicates that something has not been done properly and at the right time. 

 It may be that the pastures and meadows have been allowed to remain down too 

 long; that a suitable rotation of crops is not practised; or that there is little or no 

 fall plowing done. 



Wireworms are the grubs of click-beetles or "skipjacks," and White Grubs are 

 the grubs of June beetles, with which most persons are quite familiar. 



Wireworm.s. The adult beetles appear frequently in the spring and the 

 females deposit their eggs close to the roots of grasses or weeds. The Wireworms, 

 however, do not confine their attacks to the roots of grasses and cereals, but often 

 devour the roots of other crops and even the seeds of corn, wheat and other 

 grains. In fact there is no plant that is immune from their attacks, so far as we 

 know, although many farmers in England claim that buckwheat, mustard and rape 

 escape. The Wireworms, of which there are many species, are hard, smooth, shining, 

 yellowish-brown, wire-like grubs, and possess three pairs of short legs, hence they 

 are readily identified. 



Many attempts have been made to devise some reliable method of destroying 

 them. Some years ago Professors Comstock and Slingerland, of the Cornell Agri- 

 cultural Experiment Station, and Professor Forbes, of the Illinois Station, con- 

 ducted a very complete series of experiments extending over a number of years, 

 and found that insecticides were practically of no value. They ascertained, how- 

 ever, that certain cultural operations were valuable in destroying large numbers 

 of the transforming pupae and adults before they emerged from the cells in the 

 ground. Wireworms spend from three to five years in the ground and transform 

 to pupge and adults in the late summer and autumn. But the adults remain 

 in the pupal cells, and do not emerge until the following spring. It was de- 

 termined that these pupse and adults wintering in the pupal cells were 

 very sensitive to distributions such as late plowing produces. Plowing infested 

 or suspected sod-land twice — once in August, with a good harrowing a week later, 

 and again in late September or October — will break up many of the pupal cells 

 and expose the beetles during the winter to conditions which they cannot survive. 

 This cultural process will not interfere with the Wireworms or those in the 

 grub stage. When a sod-land is broken there will naturally be Wireworms in dif- 

 ferent stages of development, some in the first year larval stage, some in the 

 second year, and some in the third year, and others ready to pupate. Only those 

 ready to pupate will in all likelihood be killed by the fall plowing. In the follow- 

 ing season, however, the young grubs are growing rapidly; and if the dying roots 

 of the sod furnish sufficient plant food, they will not do much feeding on the roots 

 of tiie new crop, but will be more injurious the year following. Now certain 

 crops, such as clover, barley, wheat and rye, are not so liable to attack as are corn, 



