74 



Table XXVI. — Comparative injury by hollworm to early-planted and late-planted cotton. 





Early-planted. 



Per 

 cent 

 of 

 in- 

 jury. 



Late-planted. 



Per 

 cent 

 of 

 in- 

 jury. 



Per 

 cent in 

 favor 

 of • 

 early 

 plant- 

 ing. 





Locality. 



Date of 

 planting. 



Seed 

 used. 



Date of 

 planting. 



Seed used. 



Kind of soil. 



Ladonia, Tex 



Ben Franklin, Tex. 



Quinlan,Tex 



Willspoint, Tex . . . 

 Paris, Tex 



Almont, Tex 



Apr. 1 



Mar. 19 

 Apr. 1 

 Mar. 30 

 ....do... 



Mar. 23 



King. 



Hall . . 

 King. 

 ...do.. 

 Gin . . . 



King . 



23.6 



5.6 



5.5 



4.9 



19.7 



5.6 



May 2 



Apr. 15 

 Apr. 25 

 Mav 2 

 May 1 



June 2 



King 



Hall 



Gin 



Rowden . . 

 Gin 



Fleming.. 



35.3 



23.5 

 10.0 

 10.0 

 29.6 



23.6 



11.7 



17.9 

 4.5 

 4.1 

 9.9 



18.0 



Black-waxy, wood- 

 ed. 

 Do. 

 Post-oak. 

 Gray prairie. 

 Black prairie. 



Red River bottom. 



Average of all ob- 

 servations. 



9.3 



20.7 



11.4 









1 

 . i 





It will be noted that in determining the percentage of injur}^ obser- 

 vations were made on early and late cotton in the same locality and on 

 the same date, as shown in Tables XXV and XXVI, so that the com- 

 parisons are quite fair. The average total injury to earl}^ cotton was 

 9.3 per cent, as compared with an average total of 20.7 per cent to late 

 cotton. This difference is undoubtedly less than would be the case 

 during seasons of more severe bollworm injury than occurred in 1901. 

 The decided preference of the bollworm for squares and young bolls 

 is shown in the figures of average percentages of injury given in both 

 tables. Thus, the sum of the percentages of injury, as shown in the 

 tables, to squares and bolls one-half grown or less is 1^1:9.9, Avhile on 

 bolls from three-fourths to full grown the injur}^ amounts to only 11.5 

 per cent. 



The fact of the comparatively less injury to early cotton indicates 

 the desirability not only of planting as early in the spring as possible, 

 but of adopting all other practicable measures that will further the 

 production of an early crop, such as the use of seed of early fruiting 

 varieties, the use of fertilizers to hasten and increase the production 

 of fruit, and early and thorough cultivation. This subject will be 

 more fully discussed under the consideration of remedial measures. 



AMOUNT OF DAMAGE DONE BY A SINGLE LARVA. 



Owing to the very different method of attack on corn and cotton, 

 the damage done by a single larva is of an entirely different nature in 

 the two cases and will be considered separatel3^ 



DAMAGE TO YOUNG CORN. 



When the larva feeds on young corn by eating into the bud, consid- 

 erable injury is done to the unfolding leaves and the plant presents a 

 very ragged appearance. (See PI. VII, fig. 1.) From general obser- 

 vation it would seem that the small percentage of plants which are 

 injured when young must be less productive later in the season. 



