INSECTS INJURIOUS TO CORN, 



269 











1., 



• 54 ' 



a little care in searching for the larvae, one can very readily tell definitely 

 whether the work is due to these insects or not. 



The sod web-worms are the larvae of the little white or gra} colored 

 moths that one finds so commonly flying 

 up before him as he walks through the 

 grass fields during the summer. These 

 moths will fly a short distance ahead or 

 to the side and alight again upon the 

 grass, usually with their heads down- 

 ward; and when they alight, they fold 

 their wings about their bodies, so as to 

 give them a long, cylindrical appearance, 

 and except for their color, rather difficult 

 objects to find on account of the fact that 

 that they keep the body close to and 

 parallel with the blade or stem of the 

 grass on which they alight. Two species 

 of these moths with their wings expanded 

 are shown enlarged in figures 28 and 30. 

 These moths lay their eggs here and 

 there over the grass fields, including our 



1 „ iU i. r ii -u • J -i-^A Fie. 29. — The Common Sod Web- 



la WHS, the most of them bemg deposited ^J^^ crambus trlsectus. Larvae ; 



in June and July. The eggs hatch in s^eatiy enlarged, 

 about two weeks, and the larvae, which are known as the sod web- 

 worms, burrow into the ground near the base of the grass plant, and 

 feed upon the stem and the leaves surrounding it just below the sur- 

 face, and also upon the roots at the base, sometimes cutting them en- 

 tirely in two. They also burrow into the stem and frequently make tun- 

 nels or mines up the center of the stem, or along the edge, thus causing 

 irregular furrows. They will also feed upon the leaves, eating longi- 

 tudinal, irregular holes through them, frequently cutting off the leaves 

 near the base partly drawing them into their burrows or cells, which 

 they construct at the base of the plant. 



The larvae, as soon as they hatch and begin to feed, begin to con- 

 struct for themselves a little cell, usually near the surface of the ground 

 and in close contact with the stem of the grass plant or the corn plant, 

 as the case may be, and make these cells out of silk, weaving with it 

 particles of the earth, and then line it with a thick layer of silk. As the 

 larvae grow, they enlarge these cells. Figure 32 represents a corn plant 

 much reduced in size with one of these cells placed in the usual position 

 next the plant and just below the surface of the ground. The end of the 



