64 



"I send you a rough sketch of a field infested by the grass worm 

 last fall. I visited this field five times after the worms made their 

 appearance, the first visit being about October 1, and the last one 

 about December 6. 



Upon my first visit to this field I found the worms actively at 

 work in the spots marked 1, 2, 3, 4, they having seemingly begun 

 at the center of the spaces and worked in all directions. Upon my 

 second visit, the worms had eaten every green thing in space 1, 

 over an area of six or seven acres, and many of them had entered 

 the ground to pupate. In space 2 and 3 they had eaten about one 

 half of the wheat, making it look ragged and thin on the ground. 

 (The spaces indicated as 2 and 3 were about one half acre each.) 



In space 4, they had destroyed all the wheat at the center, but 

 had not extended their ravages so far as in No. 1, probably not 

 more than half an acre being entirely eaten off, while about three 

 acres was partially eaten, less damage being done as the boundary 

 was approached. 



At this time (second visit), I found more worms at work in No. 

 4 than in No. 1, but they were scattered over a relatively larger 

 space. 



When I returned on my third visit, about Nov. 7, I found No. 1 

 had been resown with the drill without plowing, while the other in- 

 fested spaces had not been resown. 



These parts of the field presented a yellowish, sickly appearance, 

 and did not recover at all before cold weather. The leaves began 

 to turn brown at the tips and dry up, while there was very little 

 if any growth from the center. Even wh^re the wheat was but 

 little eaten by the worms, it presented a stunted appearance. The 

 worms climbed upon the blades of the wheat and ate them, instead 

 of cutting off the plant at the ground, so there was but little dam- 

 aged except that actually consumed. But the ravages of this worm 

 are greater than can be accounted for by the actual amount of the 

 herbage eaten. They seem to produce an effect similar to that pro- 

 duced by a too free use of fertilizers upon growing plants. 



This field of wheat was sown upon oats stubble plowed under 

 without burning." 



Natural enemies. 



In the Southern States where the common species of ants seem 

 to be much more predaceous and ferocious in their habits than with 

 us, they apparently interpose a notable check on the multiplication 

 of the grass worm. 



"At a plantation in the vicinity of Columbus," in Georgia, says 

 Glover, "where the caterpillars were very numerous, and had already 

 devoured all the grass on one side of a field which was divided into 

 two equal parts by a broad and sandy carriage road passing through 

 the center of it, the grass on the other side having been untouched, 

 it was interesting to observe the operations of numerous colonies of 

 ants that had formed their holes or nests in the road, and were 

 lying in wait for any unfortunate grass worm, the natural desire of 



