266 MISSOURI AGRICULTURAL REPORT. 



along in the early part of the summer or latter part of the spring, pack 

 the earth away from their bodies so as to make a little earthen cell, and 

 there, a few inches below the surface, they transform to pupae. This 

 pupa stage lasts until the latter part of July or fore part of August, 

 when they transform to adults. These adults now almost invariably re- 

 main in the ground inside of their little earthen cells throughout the rest 

 of the skimmer, fall and winter, and emerge as adult beetles the follow- 

 ing May or June. This brief sketch of the life history does not apply to 

 all species in that some of them take five years to go through their trans- 

 formations, so that we have in the various species of May beetles varia- 

 tions in the time for the transformation extending from two to five years, 

 the great majority, however, requiring three years to complete their 

 life cycle. 



The white grub do their greatest amount of damage to corn that has 

 recently followed grass. It is a fact, however, that these beetles will lay 

 their eggs year after year in a corn field, and the insects can multiply 

 there, but the most prevalent method is for the insects to deposit their 

 eggs in the grass field, and for the farmer to plow these grass fields and 

 sow them to corn, in which case w^e have a greatly increased number of 

 white grub in a given portion of soil than we would have under the best 

 of conditions were the insect trying to multiply year after year in the corn 

 field. Hence newly plowed grass land will be subject to the attack of 

 these insects for upwards of two or three years following. Very fre- 

 quently such fields will contain from four to twelve white grub at every 

 hill of corn, and under these conditions one can readily see that the 

 raising of corn would be very unsatisfactory. These insects do not feed 

 to any great extent upon clover, and, therefore, in rotating the crop from 

 corn to pasture, if one would sow the same to clover, it could remain as 

 a clover field for several years and then be replanted to corn without 

 any serious injury from these insects, whereas, if the corn were rotated 

 with grass, very serious trouble would be likely to follow. 



The May beetles are much more apt to lay their eggs in corn fields 

 if the same contain any considerable amount of grass or weeds during 

 May and June, during which time these insects are depositing their 

 eggs. As these white grub will feed upon wheat, barley, potatoes, beans 

 and the like, it will not suffice to try and rotate a beetle-infested field 

 with these crops any more than with grass. Where one turns under 

 some land and sows it to corn and finds these white grub extremely 

 numerous, it would be much more satisfactory to not replant the corn 

 again, but to sow the field to clover and let it stay in clover for a year 

 or two. 



