.- Everglades Station Mimeo Report 60-4 September 15, 1959


 A Preliminary Report On

 The Corn Stem Weevil And Its Control

 By Emmett D. Harris, Jr.*


 Young sweet corn plants were heavily infested last year by small white leg-

 less grubs "boring" or "mining" within the stem near the ground level. Fifty

 percent or more of the fields in this area were affected. In many fields nearly

 100 percent of the plants were attacked. Many infested plants were stunted,

 lodged in heavy winds, or wilted and died, but some showed no obvious evidence of

 injury. Although it has not been completely shown in controlled experiments, the

 grubs appear to cause this damage.

 This insect, Hyperodes humilis (Gyll.) had not been known to damage crops

 before and does not have a common name although it has been found in the United

 States for many years. Because of its feeding habits "corn stem weevil" seems to

 be a good name.

 Eggs about 1/32 inch long are usually imbedded in the tissue of the sheath

 of the lower leaves on young corn plants. They are more easily seen when the

 leaf sheath is stripped from the plant and examined from the under surface. They

 are creamish white when first laid but in a day or two change to dark brown.

 They hatch in about three to six days.

 The grubs are white with a light brown head and legless. They are about

 1/32 inch long when first hatched and about 1/4 inch long when mature. They feed

 about 20 to 25 days before they become pupae. The pupal stage is one in which

 the insect is inactive and is changing from a larva&. to an adult.

 The pupa is white and about 5/32 inch long. Pupae have not be ..

 the field, but grubs reared in the laboratory pupated in corn sta ~ About four
 nSE 29 1959
 to nine days are spent in the pupal stage before the adult insect \jrges. A


SAssistant Entomologist, Everglads Experiment Station, Belle Glade
* Assistant Entomologist, Everglades Experiment Station, Belle Glade