The silver content of fruits and vegetables was 20 to 100 µg/kg and an average value for land plants was given as 60 µg/kg. High levels have been found in some plants, especially fungi, but no plants have been found which are regular silver concentrators. The mushroom, Clavulina cinerea, had 16 mg/kg and Caulerpa prolifera had 10 mg/kg. Ephedra gerardiana had a seasonal variation with 8 mg/kg in May and 20 mg/kg in September (Ewing et al. 1969, Horovitz et al. 1974, Cooper and Jolly 1970). Silver does not accumulate in the leaves of citrus plants grown in soil containing 75 mg silver/kg as soluble AgNO3. The leaves had only 500 µg/kg (Vanselow 1966). In terrestrial herbs, shrubs and trees, the silver content of the ash is generally low, 200 µg/kg.