ANNUAL REPORT, 1936 41 



Bordeaux 4-1-50 for the same number of applications. In one series in which 

 some plots received three applications of Bordeaux, better control of rots was 

 secured with three applications than with two. Delayed application of the 

 first spray on plots receiving only two applications probably accounts for the 

 difference in control. On this bog better control of rots was secured with two 

 or three applications of Bordeaux on plots which had been sprayed twice with 

 Bordeaux in 1935 than on plots which had not been sprayed in 1935. A similar 

 comparison could not be made on other bogs. A commercial Bordeaux (Oxo 

 Bordeaux) applied as a 4-50 or 5-50 spray at the rate of 250 gallons per acre 

 failed to control rots. The amount of copper in the deposit on leaves during 

 the season up to the time that the berries were picked shows a correlation with 

 the degree of control of fruit rots. Penetrol or Prestol with Bordeaux did not 

 improve the adherence of the spray film nor give a better control of fruit rots 

 than Bordeaux with soap. 



Sulfur sprays not only failed to reduce rots but actually caused an increase 

 as compared with adjacent checks. An oil soluble copper resinate (Palustrex) 

 in kerosene 1:4 or 4:10, with one gallon of pyrethrum extract (8 pounds of 

 pyrethrum flowers) added for each ten gallons of spray mixture and applied 

 at the rate of 10 gallons per acre; or one gallon of Palustrex (copper resinate) 

 as an emulsion in 50 or 75 gallons of water, with one quart of pyrethrum extract 

 added for each 50 gallons of diluted spray, and applied at the rate of 175-200 

 gallons per acre caused severe burning of buds, flowers, and young leaves. 

 When applied as a water emulsion, at either concentration, at the rate of 200- 

 250 gallons per acre before the flower buds began to open, there was no apparent 

 injury. The copper resinate sprays gave no control of fruit rots either when 

 applied in kerosene or as an emulsion in water. On plots on which much burning 

 injury occurred, the amount of rot was greater than on adjacent check plots. 

 Two applications of a dust made up of 3 pounds of red copper oxide, 3 pounds 

 of chemically hydrated lime and 6 pounds of Bentonite, or of a commercial red 

 oxide (A-S) at the rate of 60 pounds per acre reduced very little the amount of 

 rot present when the berries were picked but reduced the amount of rot up to 

 December 1 by 20 to 30 percent. 



DEPARTMENT OF DAIRY INDUSTRY 

 J. H. Frandseri in Charge 



Some Factors Affecting the Properties of Whipped Cream. (W. S. 



Mueller, M. J. Mack, and H. G. Lindquist.) Additional factors studied during 

 the past year were the effect of freezing milk prior to separation and the effect 

 of freezing cream on the whipping ability of the cream. 



Cream obtained from partly (13 percent solid) frozen milk was whipped with 

 no marked effect on the whipping properties. 



Partial freezing of the cream (50 percent solid), either before or after pasteuri- 

 zation, had no significant effect on the whipping qualities of the cream. Total 

 freezing of the cream before pasteurization destroyed the whipping properties 

 of the cream, while total freezing of the cream after pasteurization was only 

 slightly detrimental. 



These results have a practical significance because they indicate that if the 

 cream should be totally frozen while in the hands of the producer, most of the 

 whipping properties would be destroyed. If the cream should be frozen after 



