An Experimental Study on Two Populations of Chamaenerion Angustifolium (L.) Scop. (=epilobium Angustifolium L.) Occurring on Contrasting Soils, With Particular Reference to the Response to Bicarbonate

SUMMARY Two populations of Chamaenerion angustifolium occurring on contrasting soil types (alkaline v. acid) were studied with regard to mineral nutrition. Plants were grown from seeds of both populations on each of the soils and in culture solution with different levels of sodium bicarbonate. Differentiation between the populations in a strictly ecological sense was not established. The main effects on the growth and mineral nutrition of the populations were correlated with characteristics of the root medium rather than with the origin of the seeds. Neither chlorosis under alkaline, nor toxicity under acidic conditions occurred. There were, however, some differences between the nutritional behaviour (Ca, Fe, Na) of the natural populations and their seedlings so that the overall potential of the seeds might be much wider than that of the already‐selected, natural populations. This seemed to be confirmed by the high percentage mortality in water cultures. Amongst the plants which survived some slight physiological differences appeared but not ones which influenced dry‐weight production. It can be concluded that C. angustifolium is indifferent with regard to the soil factor pH, or better; that the species is adapted both to acid and alkaline soil. This was discussed with reference to Ca, Fe and HCO3+.