6 INSECTS IN SHIPMENTS OF SUGAR CANE. 



INSECTS OCCURRING IN THE UNITED STATES. 



THE SUGAR-CANE MOTH BORER. 



{Diatrsea saccharalis Fab.) 



The sugar-cane moth borer is easily the most important of the 

 insects injurious to sugar cane in the United States. Like other 

 sugar-cane insects it was probably introduced from the Tropics, 

 though the time of this introduction is very uncertain.^ The nature 

 of injury is only too familiar to most planters. The adult, a small 

 moth, deposits its eggs in clusters on the leaves of the cane plants. 

 These eggs hatch, and the small larvae, or borers, which emerge begin 

 to gnaw their way into the stalk. The injury in the early spring is 

 known as "dead heart," and consists of the decaying of the tender 

 shoot of the young plant. This is caused by the inner tissues being 

 severed by the borer near the surface of the ground. Later in the 

 season the borer is found in the stalks of cane, in wliich it gnaws 

 irregular tunnels. 



Mr. T. C. Barber 2 has made an investigation of the actual loss 

 directly due to the moth borer, and he summarizes his results in these 

 words : 



The sugar-caue borer damages cane in the field by destropng a considerable per- 

 centage of the eyes, thus reducing the stand of plant cane; by stunting the growth of 

 the cane, owing to the physical injury of the stem; by admitting fungous diseases 

 through the wounds in the stem, and is the main cause of injury by the wind, owing 

 to the weakening of the stalk due to the tunnels and burrows. These classes of injury 

 have been appreciated by planters. It now develops that there is another and very 

 important class of injury which has been overlooked. This is the reduction of both 

 the quantity and quality of the juice, which is dealt with specially in this circular. 

 It becomes evident that both the planters and the manufacturers are vitally interested 

 in the work of the sugar-cane borer. 



The distribution of the moth borer seems to be limited, in a general 

 way, to the southern half of Louisiana and the lower Rio Grande 

 Valley in Texas. The infestation is not uniform, but is affected by 

 local conditions. Our notes indicate that the moth borer is not to 

 be found at Sugarland and Victoria, Tex. ; at Biloxi and Ilattiesburg, 

 Miss.; nor at Montgomery and Selma, Ala. This matter should be 

 further investigated, however, as we have not had the opportunity 

 to examine very many fields at any of the places mentioned. Where 

 the moth borer is not known to occur the planters should be very 

 careful in bringing in shipments of cane from other communities, 



' Cane borer (Diatrxa saccharalis). Report of investigations by W. C. Stubbs, director, and H. A. Mor- 

 gan, entomologist. Bulletin of the Agricultural Experiment Station, second series. No. 70. Baton 

 Rouge, La., 1902. 



" Damage to Sugar Cane in Louisiana by the Sugar Cane Borer. By T. C. Barber. Circular 139, Bureau 

 of Entomology, U. S. Department of Agriculture. Washington, 1911. 



