50 GRASSHOPPERS AND OTHER INJURIOUS INSECTS OF 1911 AND 1912. 



field assistant, Mr. Harris, found these grubs being turned over 

 in the stubble field by the plow, "literally by the thousands." In a 

 field of clover, containing about thirty acres, near Granite Falls 

 about twenty acres, two-thirds of the entire piece, had been killed 

 by white grubs. On corn the injury was even more marked. In 

 two fields at least one-half of the corn was down as the result of its 

 depredations. Our field worker reported the views of nine farmers 

 as follows : 



1. The grubs were much more prevalent on land which is 

 spring plowed than that which is fall plowed. 



2. They were more plentiful where horse manure has been 

 used as a fertilizer and especially where it has been spread by hand 

 rather than with a spreader. 



3. They are found only on the higher cultivated or semi-culti- 

 vated fields away from swamps, bottom land or marshes. 



4. They have never been reported in any serious numbers be- 

 fore. 



While observations from non-scientific parties are not always to 

 be relied upon, it would appear since the above opinions appear to 

 be quite unanimous, that they are of value. In discussing No. 1 it 

 may be safely said that grubs turned up by the plow in the fall 

 would be exposed to many more dangers before spring (their period 

 of activity) than when plowed up in the spring, and the observation 

 therefore seems to be an accurate one, and also an argument for fall 

 ploiving. The beetles seem to be attracted to manure and it is na- 

 tural that eggs should be deposited more freely upon lands so fer- 

 tilized (No. 2) and particularly if the manure were left in small 

 or large piles and not spread evenly and becoming quickly dry. 

 The roots of grass appear to be the natural food of the white grub 

 (note No. 4 above) and when sod is removed it is perfectly natural 

 that the grub should turn to the food substituted for sod over the 

 same area. This accounts for the fact that corn or potatoes follow- 

 ing sod in some districts are likely to be injured. This is also true 

 of strawberry plants if set upon new land. Young spruce or 

 seedling spruce are sometimes attacked, particularly if in land used 

 for strawberries the previous year. It would appear that this 

 pest is on the increase, possibly because more land is coming into 

 cultivation. 



To be effective any treatment against this pest must be begun 

 as soon as the first signs of injury to the lawn are observed. To 

 wait until the grass is brown and dead is like shutting the door 



