wheat was the golden crop that built the economy of the prairie provinces of manitoba, saskatchewan and alberta and filled outbound trains headed for ports to carry the grain to europe. the tall grain elevator alongside the railway tracks became a crucial element of the prairie grain trade after 1890. it boosted "king wheat" to regional dominance by integrating the region's economy with the rest of canada. used to efficiently load grain into railroad cars, grain elevators came to be clustered in "lines" and their ownership tended to concentrate in the hands of increasingly fewer companies, many controlled by americans. the main commercial entities involved in the trade were the canadian pacific railway and the powerful grain syndicates. dramatic changes in the grain trade took place in the 1940s, notably the amalgamation of grain elevator companies.