36 



Entomology and Zoology Department. [Bull. 168 



his following the furrow. The truth of the matter is that it is 

 probably the white grub that attracts him, not the corn. The 

 presence of moles in rich lawns, garden plots and along creeks 

 in cornfields is a symptom, not a disease. The white grub is 

 the disease. The record of accurate observations on a twenty- 

 acre cornfield in Illinois shows an average of over thirty-four 

 grubs to the square yard. It is needless to say that this field 

 produced but little corn. The grub eats the young corn shoots 

 before they are up and attacks the root system at any time 

 throughout the season. 



The following table gives the results of careful measurements 

 and counts made day by day on twenty rows of corn in rich 

 ground along a little creek. The data given are calculated to 

 show to what extent the mole traverses or crosses the lister 

 furrow : 



PLANTING "A. 



PLANTING "B." 



The above figures give the greatest totals noted at any one 

 time. After heavy rains counts and measurements would 

 differ from these figures. Probably nearly the entire lengths 

 of the rows were traversed at different times. The injurious 

 effect of the mole's running under the young corn shoots was 

 most noticeable in the dry periods. However, the number of 

 shoots of corn known to have died from having their roots 

 heaved up totaled but 53. 



