22 NEW YORK STATE MUSEUM 



The flight from the fields to the trees begins just about dusk — 

 from a little before eight till a little after eight during the latter part 

 of June and extends over a period of only fifteen to twenty minutes 

 as recorded by Mr J. A. West. The beetles remain in the trees 

 during the night and at the break of day, about the time the first 

 bird notes are heard, namely between three and four o'clock in the 

 morning, the return to the grass fields begins and is rapidly accom- 

 plished. Experiments conducted several years ago by Professor 

 Forbes clearly show that the beetles fly considerable distances in 

 the search of food trees, since comparatively few beetles were cap- 

 tured in trap lanterns distant from trees and so protected that the 

 lights would not attract the insects from the trees. There is little or 

 no moving and feeding when the night temperature is below 52 F. 

 and the minimum for normal activities is 6o° F. Pairing occurs 

 during the feeding period at night and the eggs are deposited in balls 

 of earth about one-half of an inch in diameter and lying from one to 

 five or six inches below the surface. 



Habits of the grubs. The small, white grubs two to three months 

 old are found until in early fall at least, as shown by our observa- 

 tions, among the grass roots and within two or three inches of the 

 surface. With the approach of cold weather the grubs descend to 

 a depth of six inches or more, remaining quiescent in oval cells during 

 the winter and in the spring slowly make their way to the surface 

 and feed upon the superficial grass roots. The grubs are sluggish 

 creatures and move slowly, so that anything like a migration is 

 impossible, though conditions in infested fields plainly indicate 

 more or less of a movement from badly injured sod to the compara- 

 tively uninjured outlying grass. Occasionally the reverse is true and 

 there may be somewhat of a concentration of the grubs in a central, 

 comparatively unharmed patch. In July of the third summer they 

 construct oval cells in the soil and change to pupae, the latter trans- 

 forming to beetles in August or September and the perfect insects 

 appearing the following May or June, thus completing the three-year 

 life cycle. 



Natural enemies. White grubs are greedily devoured by pigs 

 which, where possible, should be given the run of badly infested 

 fields. The common skunk, although in ill repute because of its 

 love for chickens, searches out and destroys a great many of the 

 grubs, frequently clearing the pests from considerable areas. 



Studies in Illinois by Dr F. E. L. Beal in 1894 showed that crows 

 ate either beetles or grubs in every month of the year from March to 

 October, inclusive. The large size of this bird and its ground-feeding 



