WEATHER AND CRANBERRY PRODUCTION 11 



crop year and the sunshine and temperature of March and the rainfall of July 

 and August of the crop year. 



Four horsemen of a bumper cranberry crop in Massachusetts are: 



1. Plenty of sunshine the year before. 



2. Little or no winterkilling and little trouble with spring frosts. 



3. Two to four inches of rain each month in the growing season (pp 6, 

 14, and 15.). 



4. Light damage by insects. 



Very temporary weather occurrences, aside from those already considered, 

 seem generally to have less effect on cranberry production than is supposed by 

 many. Nothing has appeared anywhere to lend any substance to the belief that 

 low temperatures short of freezing harm cranberry buds or flowers or in any way 

 materially affect the set of the fruit. No study has been made of a possible effect 

 of heavy and persistent fogs on bee activity during the cranberry blossoming 

 period, but it may be fairly doubted whether this Is Important, for cranberries 

 are grown successfully and In fair abundance on Nantucket, the foggiest place in 

 the eastern United States. Heavy rain for a day or two in the blooming period 

 may perhaps greatly dilute the nectar of the flowers and so upset the work of 

 bees for a few days, but It Is doubtful whether it affects the set of fruit inuch if 

 it is not continued or repeated. Much interference from continual rain or fre- 

 quent early frosts retards harvesting and so finally causes the berries to be larger 

 and the crop therefore more abundant (e.g., crop of 1922, Massachusetts berries 

 larger than In any other year in which records of size have been made^^). 



It is interesting to note, in connection with Figure 1, that the cranberry acreage 

 in Massachusetts and New Jersey has not changed much since 1905,20 while 

 that In Wisconsin has increased considerably. The greater production in Mass- 

 achusetts in that time must, therefore, be due to increased acre yields. These 

 have been obtained in spite of the development here of three new major enemies 

 of the cranberry Industry: the false-blossom disease, the gypsy moth, and the 

 root grub. ' The drop In New Jersey production since 1925 must have been a per 

 acre decrease and has been generally regarded as an effect of the false-blossom 

 disease. The Wisconsin cranberry Industry, meanwhile, has had to contend with 

 the false-blossom disease but is not known to have encountered any other un- 

 usual adverse development; it has profited largely since 1933 from the use of 

 water from the Wisconsin River In the Cranmoor district. 



l^Ibid., pp. 86. 87, and 91. 



^OMass. Agr. Expt. Sta. Bui. 332, 1936, pp. 4 and 20. 



