U. S. D. A., B. K. Bui. 66, Part V. Issued January 28, 1009. 



SOME INSECTS INIHRIOUS TO TRUCK CROPS. 



THE SEMITROPICAL ARMY WORM. 



{PnxUnld ciidiiiiia Cnuii.) 



By F. H. CiiiTTKNDK.x jiiid II. M. Kussell. 

 INTRODUCTION. 



During the summer of lUOT a smooth or hairless oaterpilhir (Pro- 

 denia eridaiiia Cram.) rehited to the cotton cutAvorm came under the 

 observation of the junior author at Orlando, Fla. It was observed 

 attacking the foliage and, in many cases, the stems and fruits of all 

 forms of garden truck grown in that vicinit}', the list including 

 tomato, potato, sweet-potato, eggplant, pepper, okra, collards, and 

 cowpeas. The infestation was of considerable severity, and great in- 

 jur}^ was done in fields and gardens in that and in some other regions 

 of Florida, notably at St. Augustine and on the west coast of the 

 ]Manatee River. A^liat is believed to be the same species was reported 

 injurious in Porto Eico by Mr. W. V. Tower. Aside from a brief 

 notice which has been made of the present invasion there does not 

 appear to be an}- other record of the injurious habits of this species; 

 hence the following account has been prepared for publication by the 

 senior author. The chapters on recent injuries, natural enemies, and 

 experiments with i-emedies have been compiled from the junior au- 

 thor's notes. The technical descriptions of the egg and larva have 

 been i^repared by Dr. H. G. Dyar, Avhile other assistance in the prep- 

 aration of this article is duly acknowledged in its proper place. 



In ordinary seasons the species under consideration confines itself 

 largely to weeds, among which are the poke-weed, spiny amaranth 

 or careless weed of the South, and a wild Solanum. It has habits 

 different from those of the northern cutworms and can scarcely be 

 classified with the climbing cutworms, although it has the climbing 

 habit. It has a decided tendency to travel in armies like the army 

 worms and is practically confined to semitropical regions. It is 

 remarkable as being injurious throughout the warm season and breed- 

 ing continuously, there being evidently at least four generations a 

 year in nature. 



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