6 BULLETIN 368^ U. S. DEPAETMEXT OF AGRICULTURE. 



The spraying experiments were continued througliout the season. 

 In addition to the dormant spray of March 17, the bud spray of 

 March 24, and the calyx spray of April 8, a fourth apphcation was 

 made May 1 to 4, a fifth May 29, a sixth June 14, and a seventh 

 August 6, about a month before harvest. 



The following spray materials were used: 



Fl. Bordeaux mixture, 4—4—50. 



F2. Same as Fl, but with 2 pounds of resin-fishoil soap added. 



F3. Self-boiled lime-sulpbur, 8-8-50. 



F4. Same as F3, but \rith 2 pounds of resin-fishoil soap added. 



F5. Same as F3, but with three-fourths pound of dry powdered arsenate of lead 



added. 



F6. Commercial lime-sulphur, IJ to 50. 



F7. Commercial lime-sulphui', 1 to 50. 



F8. Same as F6, but with 2 gallons of flour paste added. 



The flour paste was made by boiling 1 pomid of flour in 1 gallon 

 of water about half an hour, until a thick paste was formed. The 

 resin-fishoil soap was purchased on the market in the East. It can 

 not be readily obtained on the Pacific slope, but may be made up 

 as follows: 



Resin 5 pounds. 



Potash lye, such as is sold for washing purposes 1 pound. 



Fish oil 1 pint. 



Water 5 gallons. 



The resin is dissolved in the oil by heating in a large kettle. After 

 this has partially cooled, the potash is added, the mixture being 

 slowly stirred and carefully watched to prevent its boiling over. 

 A part of the water is now added and the boiling continued till the 

 mixture will dissolve in cold water. This will require about one 

 hour. The remainder of the water is then slowly added and the 

 mixture thoroughly stiri'ed. The resin-fishoil soap was found very 

 valuable in making the spray adhere to the fruit. It can not be 

 used with commercial lime-sulphui*. 



It was found that the fruit was covered better when a driving 

 type of nozzle was used. None of the sprays used caused any 

 injury. The second orchard adjoined the first. The trees were 

 younger and had borne but a very light crop the previous year. 

 Apothecia were of rare occurrence in this orchard m the spring. 



The prunes were harvested September 7 to 10. A count was made 

 of the entire pitme crop of the five trees of each plat. A crate of 

 sound fruit was packed from each of the more important plats, 

 the packed samples being stored in a noncooled orchard warehouse 

 until September 14 and then shipped by express to Wenatchee, 

 Wash. The figures in the last column of Table II show the percentage 

 of brown-rot that had developed 12 days after harvesting. 



