THE SUGAR-CANE MOTH BORER. 



the bored stalks are often blown down by a strong wind. The purity 

 of the juice is lowered, the tonnage decreased, and the sucrose con- 

 tent materially diminished. The eyes are destroyed in many cases, 

 which lessens the value of the infested cane for seed. 



EFFECT ON CORN. 



The damage of the moth borer 1 to the corn plant has been well 

 described by Mr. George G. Ainslie (2). 



Corn is damaged by these caterpillars in two ways. First, in the early 

 part of the season, while the plants are small, they work in the throat of the 

 young corn, and if the tender growing tip within the protecting leaves 

 is once damaged all chances that the plant will become a normal productive 

 specimen are gone. In many sections of the South this is commonly known 

 as " bud-worm " injury, and though there are several other insects which 

 cause a similar mutilation of the leaf, a very large proportion of the so-called 

 " bud-worm " damage may be charged to this insect. The effect of its work 

 on the leaves of the young corn plants is similar to that resulting from attacks 

 by the corn billbugs (Sphenopfiorus spp.) and is evidenced by the familiar 

 rows of small circular or irregular holes across the blades of the plant. 



The other form of serious damage chargeable to this pest occurs later in 

 the season. The larvae, having then left the leaves and descended to the lower 

 part of the stalk, tunnel in the pith. If the larvae are at all numerous in the 

 stalk, their burrows so weaken the plant that any unusual strain will lay it low 

 and destroy all chance of its maturing. While frequently ten or more larvae 

 may live and mature in one plant, it must be remembered that any infestation, 

 however light, will lessen in some degree the vitality of the plant and cause a 

 corresponding loss in the quality and quantity of the harvest. 



Not only the stalks of corn, but sometimes the ears are found to 

 contain borers. 



The cornstalks, maturing about July or August, when the cane is 

 hardly half grown, become dry and the plants are no longer attrac- 

 tive to the moths for the deposition of eggs. Corn and cane are 

 grown in adjacent fields on sugar plantations, and moths from corn 

 find cane an attractive food plant. Consequently the cane in the 

 middle of the season is attacked not only by moths which have passed 

 their immature stages in cane plants, but by numbers of those which 

 have grown to maturity in corn. It is notable that the number of 

 cane stalks infested by borers increases rapidly from the middle 

 of the growing season until the cane is cut. 



HISTORY. 



Dr. L. O. Howard (77) wrote an article on the moth borer for the 

 official entomological journal, Insect Life, in 1891, introducing his 

 remarks with an account of the history of the species. We quote 

 him as follows: 



1 Though this account was doubtless written with Diatraea seacolella Dyar in mind, it is 

 correct when applied to the closely allied species D. saccharalis cramMdoides, which also 

 attacks corn. 



