14 



the present investigation many foreign entomologists were corre- 

 sponded with in countries where tliis species was known to occur in the 

 hope that important enemies of the bollworm miglit be discovered and 

 imported to this country. No important enendes, however, have been 

 discovered. 



SOME RESULTS OF FIELD WORK. 



Attention has elsewhere been called to the principal lines of field 

 work. Of first importance is the so-called cultural method, which 

 consists of the employment of all such means as will contribute to the 

 production of an earl}^ crop of cotton. This involves especially, (1) the 

 use of seed of early-fruiting varieties; (2) early planting in the spring; 

 (3) earl}' and thorough cultivation; (-i) the use of fertilizers to hasten 

 and increase the growth of the plant and the development of fruit. 



As has been stated, the cotton crops of Texas and adjacent States 

 have, until recently, been largely produced from native-grown seed, 

 often secured from public ginneries and of unknown variet}" and 

 origin. The accumulated effect of the climate has been to make the 

 crop later and later in maturing, especially in the absence of selection 

 of seed for earliness and other qualities. During years of severe 

 bollworm injury, the insects, upon their migration from ripening corn 

 to cotton in early August, have found but few fields in which the bolls 

 were sufficiently matured and hardened to be unsuitable for food, 

 and practically all of the fruit has been subject to attack. The 

 importance of early planting to avoid bollworm injury has long been 

 recognized by planters, but sufficient attention has not been given to 

 the matter of using improved varieties of seed and to the adoption of 

 improved farm practices, Man}- observers have noted that relativel}^ 

 less injur}' was done by the bollworm and other cotton pests, espe- 

 cially the leaf-worm, to early -planted than to late-planted cotton. 

 Thus Riley, as early as 18S5, says: 



Our knowledge of the natural history of Aletia [Alabama argUIacea} and the yearly 

 occurring experiences with its ravages, teach us that the principal and most effective 

 means of prevention is to hasten the maturity of the plant so that a portion of the 

 crop shall be beyond the reach of harm from the more destructive July and August 

 broods of the worm. * * * 



Improving the cotton seed in the direction just mentioned can be accouiiiiished 

 principally bj-^ careful selection of early varieties of cotton or possibly by introducing 

 seeds from more northern regions. Early planting is to be strongly urged in this 

 connection, although of course it has its drawbacks in the risks of exceptionally late 

 frosts. 



Professor Mally, in discussing certain statistics of the comparative 

 injury by the bollworm to early and late cotton in Texas in 1802, says: 



The late cotton, therefore, shows a loss of 50.6 per cent, while the earl j' cotton 

 shows no real loss. This may be taken as an extreme case, but the general principle 

 remains that late cotton receives by far the greater portion of bollworm attack, vir- 

 tually protecting the cotton fields about it. 



