The main clinical and necropsy features of field and experimental cases of suspected cardiac glycoside intoxication following ingestion and dosing of the plant Ornithogalum nanodes, are described. The distribution of intoxication in the area as well as a description of the plant are given. Plant samples tested for cardiac glycosides by fluorescence polarization immuno-assay (FPIA) gave a strong positive reaction. This is a new finding, as other toxic Ornithogalum species in southern Africa are devoid of cardiac glycoside activity and poisoning with them result only in a severe, often fatal diarrhoea, without obvious cardiac involvement. It is also the first record of toxicity of this particular plant.