REPORT OF THE STATE ENTOMOLOGIST I918 29 



Broken tassels with extruded borings at the point of injury are 

 conspicuous and easily recognized signs of infestation. It is 

 important to know that most of the tassel is affected and also to 

 keep in mind the fact that tassels may be broken from other causes. 

 The occasional hanging of one branchlet of the tassel is very rarely 

 caused by the com borer. Injury to the tassels is sometimes so 

 severe as materially to affect the fertilization of the ears. 



The small, oval, whitish feeding spots of the young borers or 

 larvae on the leaves aid in the detection of the pest, though this type 

 of injury is by no means conspicuous. 



Compared with native com insects. The European corn borer 

 is the only corn pest in America which habitually bores in the stalks, 

 in cobs and at the same time injtu*es the kernels (figure 5). It is 

 easily distinguished from the earlier appearing lined com borer and 

 the frequently associated stalk borer by the absence of well-marked 

 reddish lines. Furthermore, the lined com borer works almost 

 entirely in com 4 to 6 inches high while the European corn borer is 

 rarely seen until the com is 12 to 15 inches high. The stalk borer 

 caterpillar, with its peculiar purplish blotch near the middle of the 

 body breaking the well-defined white and purplish brown lines, can 

 hardly be confused with the dull-colored Eiiropean com borer, 

 although its work in the com is somewhat similar. Furthermore, 

 the stalk borer, when full grown may meastu-e ly inches in length, 

 whereas the European com borer is never more than i inch long. 

 The com ear worm, a native southern insect which can not winter 

 in this latitude, attacks the tips of ripening ears, the greenish or brown- 

 ish strongly marked caterpillars are over an inch long when full 

 grown and very different from the European corn borer. Samples 

 of corn stalks suspected of being infested by this pest should be sent 

 to the farm bureau agent or the nearest entomologist. 



Life history and habits. It is necessary to distinguish sharply 

 between the habits of this insect in New York State and in Mas- 

 sachusetts. A study of the insect in the vicinity of Schenectady 

 shows that it passes the winter as a nearly full-grown borer which 

 begins to change to the pupa in June. The first moths emerge in 

 June or early July, continue on the wing about a month; there 

 being one brood. There are two broods or generations of this 

 insect in eastern Massachusetts. The nearly full-grown caterpillars 

 in either locality winter in the stems or stalks of corn and various 

 other plants. The moths appear on the wing in Massachusetts 

 from the middle of May to the latter part of June and in New York 

 State during June and into July. They are nocturnal in habit and at 



