24 BULLETIN* 636, U. S. DEPARTMENT OF AGRICULTURE. 



believe in the application of the first spray, made for the San Jose 

 scale. Heavy losses have been suffered, in the past from this pest, 

 •and now a great deal of attention is given to its control. When all 

 growers spray with a dormant lime-sulphur spray of a strength vary- 

 ing from 1 to 8 to 1 to 11, it apparently holds the scale in check, so 

 that little damage to the fruit is experienced. Applications of this 

 dormant lime-sulphur spray are made every year, usually during the 

 latter part of March or the first of April, after the buds begin to swell. 



The usual spraying crew consists of three men and two horses, two 

 men using the two leads of hose, and the third man driving the team. 



The average crew will spray 3.31 acres in 10 hours, applying 388.56 

 gallons per acre, or 6.14 gallons per tree. The labor cost is $2.56 per 

 acre, and the material cost $7.29, making a total cost of $9.85 per 

 acre, or $0.0292 per box. (See Table XL) 



The first lead-arsenate spray of the season, known as the calyx 

 spray, is made for the control of the codling moth. This application 

 is made when about 80 per cent of the petals have fallen, which is 

 usually the first or second week in May. It ordinarily consists of 

 lead arsenate and water, paste lead arsenate being used at the average 

 strength of 8 pounds to a 200-gallon tank of water, or dr} T lead arsenate 

 4 pounds to a 200-gallon tank of water. Lime-sulphur or atomic 

 sulphur, sometimes used in this spray for scab prevention, is not as 

 yet used by any of these growers. In applying this spray the average 

 crew will spray 3.69 acres in 10 hours, applying 378.09 gallons per acre, 

 or 5.97 gallons per tree, with a labor cost of $2.31 and a material cost 

 of $2.00, or a total cost of $4.31 per acre. 



The second spray for the control of the codling moth usually is 

 made about three weeks later than the first and is spoken of as the 

 " three weeks' spray." In severe cases, however, a spray is made 10 

 days after the time the petals fall, using the same strength of lead as 

 in the case of the calyx spray. The third, and usually the last, 

 application is made during the last week of July. Where four appli- 

 cations are made, the second usually follows the calyx in about 10 

 days, the third about the first of June, and the fourth the latter part 

 of July. As a rule, however, either the second or fourth spray is 

 omitted, making a total of only three applications of lead for the con- 

 trol of the codling moth larvae. For these lead sprays other than the 

 calyx spray, the average crew will spray 3.65 acres per day, applying 

 about 1,350 gallons in this time. 



Considering all sprays, the total labor cost for spraying is $9.78, 

 while the total material cost is $13.43, making a total of all costs for 

 labor and material of $23.21 per acre, or $0.0689 per box. The cost 

 of the spray rig itself, including the gasoline, upkeep, etc., is not 

 included here, but is included under the annual equipment charge to 

 be found under the fixed costs. 



