| Plant | Low PPM | High PPM | StdDev | *Reference | |
|---|---|---|---|---|---|
| Senna alexandrina | Leaf | 0.4 | 1.9 | -0.5 | * |
| Eriodictyon californicum | Leaf | 0.4 | 1.7 | -0.5 | * |
| Thymus vulgaris | Leaf | 0.3 | 1.5 | -0.5 | * |
| Aloe spp. | Leaf | -- | 1.1 | -0.5 | * |
| Citrus sinensis | Fruit | 0.9 | 13.0 | -0.5 | * |
| Verbascum thapsus | Leaf | 0.2 | 0.4 | -0.5 | * |
| Lobelia inflata | Leaf | 0.1 | 0.4 | -0.5 | * |
| Polygala tenuifolia | Root | -- | 12.0 | -0.5 | * |
| Salvia miltiorrhiza | Root | -- | 12.0 | -0.5 | Chen, H.C. and Lin, S.M. 1988. Determination of Mineral Elements in Certain Crude Drugs (Part 1), Kaohsiung J. Med. Sci., 4: 259-272. |
| Averrhoa carambola | Fruit | 1.0 | 12.0 | -0.6 | USDA's Ag Handbook 8 and sequelae) |
| Cornus officinalis | Fruit | -- | 12.0 | -0.6 | * |
| Pinellia ternata | Tuber | 14.0 | 18.0 | -0.6 | * |
| Mangifera indica | Fruit | 0.4 | 11.4 | -0.6 | * |
| Cocos nucifera | Seed | 9.0 | 25.0 | -0.6 | * |
| Firmiana simplex | Seed | -- | 25.0 | -0.6 | * |
| Ipomoea batatas | Root | 2.0 | 11.0 | -0.6 | * |
| Pinus echinata | Shoot | 6.0 | 88.0 | -0.6 | * |
| Castanea dentata | Seed | 10.0 | 24.0 | -0.6 | * |
| Chenopodium album | Seed | -- | 24.0 | -0.6 | * |
| Vitis vinifera | Stem | -- | 75.0 | -0.6 | Pedersen, M. 1987. Nutritional Herbology. Pederson Publishing. Bountiful, Utah. 377 pp. |