RELATION OF WEATHER TO THE KEEPING QUALITY 

 OF MASSACHUSETTS CRANBERRIESi 



By Neil E. Stevens^ 



CONTENTS 



What is meant by "good" keeping quality 68 



The storage period for the different varieties 69 



Variation in the keeping quality of the cranberry crop as a whole 70 



Determining the keeping quality of the crop 70 



The keeping quality of Cape Cod cranberries during the past twenty-three years 71 



The margin between "good" and "poor" keeping quality 73 



The trend toward better handling of fruit 73 



Precipitation in relation to keeping quality 74 



Temperature in relation to keeping quality 74 



Size of crop in relation to keeping quality 75 



The interrelation of the different factors 76 



The experiment in forecasting 80 



Incubator tests of keeping quality 80 



Supplementary note, January 1943 83 



What Is Meant by "Good" Keeping Quality 



"Good" and "poor" with reference to the keeping quality of cranberries are, 

 of course, relative terms and vary with the variety under discussion and with 

 the locality in which it is grown. The keeping quality of berries is judged in- 

 evitably in terms of commercial practice. If the fruit of a given year satisfies 

 what is usually demanded of it, the quality is said to be "good"; otherwise, it is 

 called "poor." 



The records of the New England Cranberry Sales Company and the American 

 Cranberry Exchange show that over a period of years the peak of the shipping 

 season for Early Blacks is usually reached the third or fourth week in September. 

 The shipping season for Howes is more variable and during the ten-year period, 

 1925-1934 inclusive, the peak came twice (1925 and 1926) the first week in Novem- 

 ber, three times (1927, 1928, and 1929) the second week in November, once 

 (1934) the third week in November, once (1930) the first week in December, 

 once (1931) the second week in December, and twice (1932 and 1933) the third 

 week in December. Allowing two weeks for the berries to reach market, it is 

 evident that in the average year most of the cranberries of the Early Black variety 

 have reached the consuming centers by the middle of October, while the Howes 

 cranberries are shipped during November and December. 



The handling of the so-called "odd" varieties seems to be well standardized 

 and the bulk of this type of fruit is disposed of about the time of the Thanks- 

 giving market. Obviously, the demands actually made on the berries vary greatly 

 with the size of the crop and with market conditions. For example, the 1921 

 crop of Early Black cranberries was almost all shipped by the end of the second 

 week in October and very few berries of any kind remained in the hands of the 



^Several progress reports and discussions of certain phases of these studies on the relation be- 

 tween weather and keeping quality have been presented in various earlier papers by the writer; 

 viz., Yearbook, U. S. Dept. Agr., 1927, pp. 238-240; Proc. Fifty-Third Ann. Meeting Amer. Cran- 

 berry Growers' Assoc, 1923; Proc. Fifty-Ninth Ann. Meeting Amer. Cranberry Growers' Assoc, 

 1929, pp. 8-16; Phytopathology, 22:911-916, 1932. In addition, "forecasts" were pubUshed reg- 

 ularly during September of each year, 1923 to 1929, in the Wareham Courier, and for 1930 to 1933 

 in the Plant Disease Reporter. 



'Formerly Senior Pathologist, Division of Fruit and Vegetable Crops and Diseases, Bureau of 

 Plant Industry, United States Department of Agriculture. Since 1936, Professor of Botany, 

 University of Illinois; and summers. Cranberry Specialist in the Wisconsin Department of Agri- 

 c ulture. 



(68) 



