A statistical evaluation of the relationship between cranberry yield in New Jersey and meteorological factors

Abstract

The relationship between meteorological variables and cranberry yield was statistically evaluated using a variety of techniques including χ 2, principal component and multiple regression analyses. The analyses were performed on overlapping 3-week periods during the harvest year, defined here as April 5 of the year prior to harvest through October 31 of the crop year, and on overlapping accumulations of 84°C growing degree days (GDD) throughout the critical development periods, May 10–June 30 of each harvest year. As a result of the dramatic increases in cranberry production after 1949, which were apparently due to non-meteorological factors, three periods were analyzed. These periods include the full length of record, 1906–1984, and the periods 1906–1949 and 1950–1984. Temperature and sunshine appear to have the greatest effect on cranberry growth and production. Precipitation, snow cover, estimates of potential evapotranspiration, and available soil moisture are apparently of little importance. Increased berry production is associated with warm temperatures during mid-May to late June and mid-October to mid-November of the year prior to harvest. Cold temperatures during early February to late March and sunny conditions from early May to mid-June also favor above-normal yields. Excessive heat from mid-June to early August and between the accumulation of 392 and 504°C GDD correspond to below-normal production. Physiological bases for these findings are discussed.