| Plant | Low PPM | High PPM | StdDev | *Reference | |
|---|---|---|---|---|---|
| Rosa laevigata | Fruit | -- | 2830.0 | 0.3 | * |
| Rosa canina | Fruit | 260.0 | 1390.0 | -0.3 | * |
| Rosmarinus officinalis | Plant | 2142.0 | 2483.0 | -0.5 | USDA's Ag Handbook 8 and sequelae) |
| Rosmarinus officinalis | Leaf | 910.0 | 2825.0 | -0.5 | USDA's Ag Handbook 8 and sequelae) |
| Rubia cordifolia | Root | -- | 1870.0 | -0.4 | * |
| Rubus chingii | Fruit | -- | 2740.0 | 0.3 | * |
| Rubus chamaemorus | Fruit | 270.0 | 1875.0 | -0.1 | * |
| Rubus idaeus | Leaf | 539.0 | 3190.0 | -0.4 | * |
| Rubus idaeus | Fruit | 175.0 | 1400.0 | -0.3 | Revised USDA data received 1993. |
| Rumex crispus | Root | 822.0 | 3200.0 | 0.3 | * |
| Rumex acetosa | Leaf | 460.0 | 4600.0 | 0.2 | * |
| Ruscus aculeatus | Root | 707.0 | 2340.0 | -0.1 | * |
| Salix alba | Bark | 941.0 | 5600.0 | 2.6 | * |
| Salvia miltiorrhiza | Root | -- | 3230.0 | 0.4 | 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. |
| Salvia officinalis | Leaf | 444.0 | 2830.0 | -0.5 | * |
| Sambucus nigra | Fruit | 265.0 | 1635.0 | -0.2 | * |
| Santalum acuminatum | Fruit | 400.0 | 1715.0 | -0.2 | * |
| Sassafras albidum | Stem | 77.0 | 4760.0 | -0.0 | * |
| Sassafras albidum | Leaf | 990.0 | 6800.0 | 1.0 | * |
| Schisandra chinensis | Fruit | 414.0 | 2760.0 | 0.3 | * |