REGRESSION ANALYSES OF CANADIAN PRAIRIE CROP-DISTRICT CEREAL YIELDS, 1961–1972, IN RELATION TO WEATHER, SOIL AND TREND

Abstract

Macroscale analyses relating crops to weather and soils have important applications, such as that of obtaining equations for use by marketing agencies in assessing regional crop prospects. To help meet such needs, regression analyses were performed on 12 yr of crop-district cereal yields. From 57 to 86% of the yield variation was explained by precipitation, potential evapotranspiration, soil texture, topography and trend terms, or generally more than twice as much as could be accounted for using only texture, topography and trend. Yield variation, and the proportion of it that could be explained, was greatest in the Brown soil zone and least in the Black, Gray and Dark Gray zone. Less of the variation could be explained for wheat than for oats and barley. In analyses of 10-yr subsets of the 12 yr, the proportion explained was considerably less for 1963–1972 than for other combinations of years.