SELENIUM IN SOILS, GRAINS, AND PLANTS IN ALBERTA

Abstract

Two hundred and twenty-seven samples of wheat, forty soils, and four plants of the Astragalus family, all from the province of Alberta, have been analysed for their selenium content. The selenium content of the soils varied from less than 0.1 to 1 p.p.m., that of wheat, from less than 0.1 to 1 p.p.m., and that of Astragalus plants, from 0.3 p.p.m. in the root of one plant to 600 p.p.m. in the stalks of another. The majority of the wheat samples contained only traces of selenium, and in no case can any one be considered as dangerous. Some of the soils contained over 0.5 p.p.m. of selenium and these may be looked upon as seleniferous. Not enough data are available to indicate the extensiveness of seleniferous soils. Although the underlying strata of much of Alberta is of Upper Cretaceous Age, the soil is derived mostly from glacial drift formed from other types of rock, so that the seleniferous area may be much smaller than that earlier suspected. Analyses of wheat and soils indicate that dangerous areas are more likely to be found in southern Alberta than in central Alberta. Analyses of vetches show that the amount of selenium absorbed is independent of the species and the selenium content of the soil and varies with the part of the plant examined.