44 MASS. EXPERIMENT STATION BULLETIN 355 



January. Seedlings from crosses made in 1936 were set out on the bog during 

 the summer. In October some 435 cuttings of seedlings from crosses made from 

 1934 to 1936 inclusive were sent to the U. S. Horticultural Station at Beltsville, 

 Maryland, to be rooted and then, in the spring of 1939, to be sent to New Jersey 

 to be tested for resistance to false blossom. 



Studies on Flower and Fruit Production. (H. F. Bergman and W. E. Truran.) 

 The number of flowers and fruits formed on uprights from terminal buds of large, 

 medium, and small size was determined on the State Bog on approximately 1000 

 uprights of each of the three varieties, Early Black, Howes, and McFarlin. In 

 Early Black large terminal buds produced more uprights with five flowers, med- 

 ium terminal buds more uprights with four flowers, and small terminal buds more 

 uprights with three flo>vers than with any other number. This held true, in 

 general, in the other two varieties, except that in Howes on fection 13 both large 

 and medium terminal buds produced more uprights with five flowers than with 

 any other number. The average percentage of flowers which produced fruit was: 

 Early Black, section 5, 23.8 and section 14, 10.7; Howes, section 7, 14.6 and 

 section 13, 17.2; McFarlin 23.4. These percentages, even the largest, are low; 

 the normal average for any of the three varieties varies from 30 to 35 percent. 

 In Early Black on section 14, in 1933, 45 percent of the flowers produced fruit 

 and only in one year during the last seven has the percentage of flowers which 

 produced fruit been as low as in 1938. The former year was 1935 when the per- 

 centage of flowers which produced fruit, in Early Black, varied from 18 to 22. 

 In Howes and McFarlin, in 1935, the percentage was somewhat higher than in 

 Early Black but was still below the normal average. The lowest previous average 

 for Howes was in 1936 on section 13, when only 19 percent of the flowers produced 

 fruit. The very low production of fruit in 1938 is to be attributed in part prob- 

 ably to prolonged rain (7-10 days) during the blossoming period which interfered 

 with pollination, and in part to hot weather during July and August which pro- 

 moted the development of fungi that caused many of the very young fruits to 

 blast. 



Spraying Experiments for Control of Rosebloom. (H. F. Bergman and W. E. 

 Truran.) One application of Bordeaux 5-2-50 at the rate of 150 to 250 gallons 

 per acre gave complete control of rosebloom on three bogs on which tests were 

 made. Rosin fish oil soap, casein, or sodium salts of sulfonated diphenyl com- 

 pounds as spreaders were equally effective On plots on the State Bog which 

 had been sprayed for rosebloom control in 1937, the amount of rosebloom in 

 1938 was very small as compared with the amount on areas not sprayed in 1937. 



Spraying Experiments for Fruit Rot Control. (H. F. Bergman and W. E. 

 Truran.) Bordeaux 5-2-50 and red copper oxide (Cuprocide), 2 pounds with 

 2H pounds of bentonite to 50 gallons of water, were about equally efi'ective in 

 rot control and were superior to all but one of the spray combinations used this 

 year. These sprays reduced the rot to one-half to one-third of that in the check 

 plots at the time of picking. Also spoilage did not proceed as rapidly during the 

 storage period in berries from plots on which these sprays were used as in those 

 from unsprayed plots, so that at the end of the storage period on December 1 

 the beneficial eff'ect of spraying was more apparent than at the time the berries 

 were picked. The use of 1 pound of rosin fish oil soap, 1 quart of penetrol, 1 

 quart of Sunoco spray oil or 2/3 to 1 pound of Areskap or Santomerse in 50 gal- 

 lons of Bordeaux spray as the spreader made no difference in the control afforded 

 by the Bordeaux. When }/^ pound of Areskap was used with Bordeaux, rot control 

 was definitely less effective than when the larger amounts of Areskap were used; 

 and when the amount of Areskap was reduced to 2 ounces to 50 gallons of spray 



