The European Corn Borer. 29 
THE STALK-BORER.”® 
The stalk-borer (Fig. 23) is often very numerous during the early 
summer in some sections of the country. It works habitually within 
the growing tip (heart) and stalk of young corn, and is frequently 
mistaken for the European corn borer on account of its habit of bor- 
ing in the cornstalks. In addition to corn, it also bores in the stalks, 
and infrequently in the fruit, of several other cultivated crops and 
flowers, and in weeds. 
The young caterpillars of the stalk-borer are very easy to distin- 
guish from the corn borer, as they bear a dark-brown or purple band 
around the middle of the body, and several conspicuous brown or 
Fig. 25.—Stalk-borer : a, Female moth; b, half-grown larva, or borer; c, full-grown larva 
in injured stalk; d, side view of segment of abdomen of same; e, pupa. All somewhat 
enlarged. (Chittenden. ) 
purple stripes run lengthwise of the body. The corn borer does not 
possess these conspicuous bands or stripes. As the stalk-borer be- 
comes full grown, however, these bands and stripes disappear and 
the color becomes plain creamy white or light purple, with only in- 
conspicuous markings. The full-grown stalk-borer is shghtly over 
an inch long and is much larger throughout than the corn borer. It 
is never found in cornstalks during the winter. 
THE SMARTWEED BORER.?*? 
The smartweed borer is very frequently found in corn during the 
autumn, winter, and spring. The appearance and work of this native 
borer resemble that of the European corn borer so closely that it is 
very difficult to distinguish between them. The smartweed borer 
usually feeds within the stems of smartweed,** but it commonly bores 
into the stalks of corn and other plants when seeking winter quarters. 
2 Papaipema nitela Guen. ®t Polygonum spp. 
39 Pyrausta ainsliet Heinrich, 
