COST OF PRODUCTION OF APPLES, PAYETTE VALLEY, IDAHO. 23 



upkeep, and interest, together with $0.74 for oil and gasoline, making 

 a total annual charge of $4.87 per acre for the use of the spray rig and 

 engine. Those who hire their spraying done pay for the rig itself 

 about $0.50 per hour, wages of man and team making up the remainder 

 of the charge of $1 per hour. Allowing the same number of spray 

 hours per acre for those who hire the spraying done, there would then 

 be an annual charge of $5.73. In reality, however, there are usually 

 fewer hours spent per acre fbr those who hire than for those who do 

 their own spraying. There is an average of 10 spray-rig hours an 

 acre for those who hire the spraying done, thus making the annual 

 cost $5 per acre, or $0.13 more per acre than for those who own their 

 spray rig. 



Most spray rigs have two leads of 50-foot rubber hose and use an 

 8 to 10 foot spray rod. The pressure varies from 125 to 275 pounds, 

 but usually is about 200 pounds. 



There are many orchard pests and diseases which the grower finds 

 it necessary to control. The most important pests are the San Jose 

 scale and the codling moth. These made their appearance in the 

 early years of the commercial apple industry in this region. There 

 are others which require less attention and which the growers in this 

 section have had little trouble in combating as yet, such as the 

 green aphis, woolly aphis, oyster-shell bark louse, blister mite, etc. 



Table XI. — Payette spraying 'practices and costs (38 records). 





Aver- 



Per acre. 



Acres 

 per 

 10 



hours. 



Gal- 

 lons 

 per 

 acre. 



Gal- 

 lons 

 per 

 tree. 



Per acre. 



Total 



cost 

 per 

 box. 





Kind of spray. 



age 



num- 

 ber of 

 sprays. 



Man- 

 hours. 



Horse- 

 hours. 



Labor 

 cost. 



Mate- 

 rial 

 cost. 



Total 

 cost. 



Strength of 

 spray. 



Lime - sulphur 

 dormant spray. 



Calyx or first lead 

 arsenate spray. 



Other lead -arse- 

 nate sprays. 



1.00 

 1.00 



2.09 



8.24 

 7.51 



15.96 



6.05 

 5.42 



11.45 



3.31 

 3.65 



388.56 

 378.09 



776.49 



6.14 

 5.97 



12.27 



$2.56 

 2.31 



4.91 



$7.29 

 2.00 



4.14 



$9.85 

 4.31 



9.05 



$0.0292 

 .0128 



.0269 



lto9. 



2 lbs. lead to 



50 gals. 



water. 

 2 lbs. lead to 



50 gals. 



water. 



Total all sprays. 



4.09 



31.71 



22.92 



3.57 



1,543.14 



24.38 



9.78 



13.43 



23.21 



.0689 





The more important apple diseases are blight, mildew, and apple 

 scab. Blight is by far the most serious, and as yet there is no effective 

 remedy other than cutting out the infected parts 6 or 7 inches below 

 the infection, using great care to disinfect the tools with corrosive 

 sublimate. Mildew and scab are present and have caused considerable 

 trouble. The apple scab made its first appearance in Idaho in Latah 

 County, in 1897, being noticed at a much later date in Canyon County. 

 The growers considered in these records, however, had not made a 

 practice of spraying to prevent either of these diseases up to the time 

 these data were taken. It was found that all growers thoroughly 



