iNSECtS INJURIOUS TO CORN. 



271 



Tiie sod web-worms all pass the winter as hibernating, partially grown, 

 larvae, which may be found inside of the webs or cases next to the base 

 or stems of the infested plants, the case being stopped up at the upper 

 end by silk thread and the inside lined with more silk. At the approach 

 of warmi weather these larvae revfve and come forth to feed upon the 

 grass or the corn plant, as the case may be. 



While most species of cut worms cut the corn plant down in the 

 spring of the year by eating it off near the surface of the ground, the 

 sod web-worms rarely ever cut a plant down, but feed upon it and kill 

 it as above described. When one finds the sod web-worm, they can 

 be distinguished from cutworms by the fact that when disturbed they 

 will try to get away as rapidly as possible, while a cutworm when dis- 

 turbed will curl up and remain sluggish. But of course the corn grower 

 can, by looking about the base of the corn plants, find the webs or cells 

 of these insects and usually find the larvae in them, in which case he can 

 readily determine the cause of the injury. By even pulling up the young 

 corn plants the case can be readily found. 



The sod web-worms, like our cutworms, prefer 

 to feed at night, but will also feed on dark days, 

 usually passing the daytime inside of their tubes, 

 which tubes, when they contain full grown larvae, 

 are usually from one and one-half to two inches 

 long and about one-half inch in width. Two species 

 of the sod web-worms in the larval condition are 

 shown enlarged in figures 29 and 31. 



The methods of fighting the sod web-worms are 

 very similar to those described for cutworms, the 

 dift'erence being mainly in the time of the applica- 

 tion of the methods of procedure. Sod land that 

 is badly infested with these insects should be plowed 

 in the early part of September, if the field is in- 

 tended for corn the next year, or if it is not plowed 

 in the fall, it should be plowed the last of May. 

 Plowing of the field the first of September will pre- 



xS:r^ 



Fig. 32.— The Sod Web- 



\v o ;■ 111 (Cranibas) : 



web (a) containing 



vent the adult moths from depositing their eggs in corn^' pian't^^^'^b^^ c °"iri? 

 that field, as they will then seek a grass field that ^"""" '° '"'^' ana stem, 

 has not been plowed under, in order to deposit their eggs for the brood 

 which hibernates in a partly grown larval condition during the winter ; 

 or, by plowing the land in May, and sowing to corn soon after, one will 

 escape the larvae of the first summer brood. We cannot poison these 

 insects by any of the means used for cutworms, as they do not seem to 



