2 



As a means, however, of destroying the overwintered weevils on 

 volunteer cotton, a spraying of poison in April promised very valu- 

 able results, and a recommendation for such treatment was inserted 

 in the last edition of the boll-weevil circular (Circular No. 18, second 

 series), as follows : 



The beetles which have survived the winter collect in the early spring on the 

 first sprouts which appear on old cotton and eat the partially expanded leaves 

 and the tender leaf stems, and at this stage can be poisoned by the application 

 of an arsenical to this new growth. To do this it will be necessary to thoroughly 

 spray the growing tips, and this should be done when volunteer cotton is very 

 small, preferably mere sprouts or bunches of leaves an inch or two in length ; 

 later on the growing parts can not be easily reached. With an ordinary knap- 

 sack pump a field may be gone over rapidly and the volunteer cotton thoroughl}' 

 treated, the nozzle being directed at each growing tip. The first application should 

 be made as soon as the volunteer-plants sprout, and perhaps repeated two or three 

 times within as many weeks. As ordinarily cultivated, the number of volun- 

 teers is small aud the time requir.'d for the thorough spraying of such plants will 

 not be great. A strong solution should be npplied, viz, 1 pound of the poison to 

 50 gallons of water, because no harni will be done if the volunteer plants are 

 ultimately killed by the poison. 



The use of poisons, either London purple or Paris green, as described 

 in the paragraph quoted, is thoroughly practicable and undoubtedly 

 will be of value. The careful study, however, of the weevil dam- 

 age in Texas conducted by the Division during the last three or 

 four years has demonstrated that the prevention of weevil damage is 

 more a question of the adoption of a proper system of cultivation 

 than of remedial or preventive schemes, such as the use of poisons. 

 In other words, it is admitted by intelligent planters everywhere that 

 the presence of the weevil is made possible by a system of culture 

 which admits of the existence of volunteer cotton, and if the methods 

 followed are such as to prevent such volunteer growth the weevil 

 will rarely if ever be troublesome. 



In our publications on this insect, therefore, great stress has been 

 given to the cultural method of control, which is undoubtedly the one 

 thoroughly effective means of avoiding loss from the boll weevil. 

 The details of this method are repeated at the close of this circular. 



Unfortunately a great deal of the cotton culture in Texas is of the 

 rather careless sort, and there probably always will be more or less 

 volunteer cotton in fields unless very stringent regulations are passed 

 and great care is taken to see that these are strictly enforced. The 

 poisoning of volunteer cotton in early spring remains, therefore, a 

 procedure of importance and of considerable practical utility. 



The present season attention has again been directed to this or a 

 very similar method of control, in the course of the investigation of 

 the weevil conditions in Texas by Professor Townsend, a field agent 

 of the Division. In the course of this work it was discovered that 



