41 



to tlie extremely wet winter and the very late spring of 1903, little 

 cotton conld be planted until the latter part of March or the first part 

 of April, In such a season as this, therefore, cotton must be small 

 at the time of the emergence of the weevils from hibernation, and 

 some time must elapse before the formation of the first squares fur- 

 nishes the weevils with their normal food supply. During this inter- 

 val the weevil gets most of its food from the tender, rapidty growing 

 terminal i)ortion of the young plants, as several observers have noted. 

 The central bud, young leaves, or tlie tender stems are attacked and 

 upon these the weevils easily subsist until squares are developed, aftei 

 which they confine their injury to them. 



The earliest plants in a field seem to attract most of the weevils, 

 and where seppa'^' plants occur they serve as excellent traps to draw 

 the first attacks. Thus, in the spring of 1895 Mr. E. A. Schwarz found 

 the first emei'ged hibernated weevils working upon seppa plants which 

 had sprung from 2-year-old roots. These i^lants seem to start earlier 

 and grow more vigorously tlian do those from seed and are therefore 

 doubly tempting to the hungry weevils. 



In 1890 Mr. Marlatt noted "the eating in the field on volunteer cot- 

 ton is ]3ractically confined to the young expanding leaves at the bud 

 and to the tender petioles or stems of this portion of the plant." 



In the spring of 1903, in one field of comparatively early cotton, 2 

 or o acres in extent, the writer found, between April 24 and Ma}^ ll, 

 23 weevils working on the buds and tender leaves of seppa plants 

 before a single weevil was found upon the young planted cotton hav- 

 ing from 4 to 8 leaves. 



If, however, the cotton should be further advanced at the time the 

 weevils appear, they would then go at once to the squares. Even 

 then they ijrefer to attack the most advanced plants, which have a 

 number of nearly grown squares, rather than the smaller plants which 

 are but just beginning to square. Seppa plants, where such exist, 

 come in, therefore, for a large part of the first attack of the hibernated 

 weevils. This fact is well shown by observations made b}'^ Mr. A. N. 

 Caudell, of the Division of Entomology, at Victoria, at about the 

 middle of June, 1902. In an examination of 100 seppa plants growing 

 in a planted field he found that fully half of the squares upon those 

 plants were then infested. The planted cotton was just beginning to 

 form squares, and was but slightly injured at that time. 



INCREASE IN LEAF AREA OF COTTON. 



The advisability of making observations upon this point was sug- 

 gested by the attempts made to jjoison hibernated weevils b}^ si)raying 

 early cotton with an arsenical insecticide. As the weevils fed so 



«•' Seppa " is the term used by the Mexican residents of South Texas to differ- 

 entiate the cotton plants springing from the roots of the previous year from those 

 strictly "volunteer," springing from accidentally scattered seeds. 



