4 BULLETIN" 382, U. S. DEPARTMENT OF AGRICULTURE. 



gain in yield must not be considered as being net profit, since there 

 are certain expenses to be charged against the value of this increased 

 production. These are the actual labor involved in the control op- 

 eration and the effect of diverting the labor from the usual opera- 

 tions to those of weevil control. 



Careful studies were made on the labor involved in these square 

 pickings and the figures secured from the experimental tests were 

 also checked under conditions more closely approximating those of 

 plantations. From these studies it was found that the average labor 

 per acre involved in the pickings ranged from about -1 hours for the 

 first to about 24 hours for the fifth. The general average of all the 

 pickings was slightly over 11 hours per acre per picking. As the 

 labor day in the Delta section is usually of about 12. hours during 

 the spring, this indicates that the pickings would average about 1 

 day's labor per acre, or a total of 5 days for the five pickings. As 

 the greater part of the picking is done by women and children, this 

 labor probably has a value of not more than 50 cents per day on the 

 average. This would make the five pickings cost about $2.50 per 

 acre on a wage basis. Of course this labor will vary greatly with the 

 locality, field, and seasonal conditions, as these factors will determine 

 the number of fallen forms present to be picked. Heavy infesta- 

 tion, producing a large number of fallen infested forms, will, of 

 course, require much more labor per acre to control, while a lighter 

 infestation, particularly on thin, sandy land, where the square for- 

 mation is not so profuse, will result in comparatively few forms to 

 be collected, and the labor required will be lessened. Under certain 

 conditions of soil and climate there is frequently a very heavy shed- 

 ding of uninjured forms. Of course these can not be distinguished 

 from the infested forms when on the ground, and must be gathered. 

 This condition occasionally becomes so pronounced that it greatly 

 increases the labor involved in picking. 



The time interval between pickings in this test (7 days) was 

 selected arbitrarily, but it is probably about the most satisfactory 

 period. This gives an interval sufficiently short to prevent any con- 

 siderable weevil emergence from the fallen forms between pickings 

 and is still about as long as can be safely allowed. The number of 

 pickings must depend entirely on the conditions prevailing. The 

 object of the number utilized in this test was to cover the period 

 from the first falling of squares in considerable numbers to the time 

 when the work becomes too bulky to handle. As previously men- 

 tioned, in an ordinary year the operation would probably start 

 earlier than was necessary in 1915, but, owing to the rapid increase 

 in the labor required during the later pickings, it would probably 

 not be profitable to give more than four pickings under ordinary 



