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| Chemical Name | Dosage | Reference |
|---|---|---|
| ZEARALENONE | not available | Duke, 1992 * |
| Plant Name | Common Name | Chemical Count | Total Parts Per Million |
|---|---|---|---|
| Quercus rubra | Northern Red Oak | 1 | 84 |
| Quercus stellata | Post Oak | 1 | 25 |
| Quercus velutina | Black Oak | 2 | 31 |
| Raphanus sativus | Radish | 1 | 64 |
| Rauvolfia serpentina | Indian Snakeroot; Serpentine Wood | 2 | 0 |
| Rauvolfia tetraphylla | Four-Leaf Devilpepper; Pinque-Pinque | 1 | 0 |
| Rauvolfia vomitoria | African Snakeroot | 1 | 0 |
| Rehmannia glutinosa | Chinese Foxglove | 1 | 0 |
| Rheum officinale | Chinese Rhubarb | 3 | 9, 000 |
| Rheum palmatum | Chinese Rhubarb | 4 | 2, 721.5 |
| Rheum rhabarbarum | Rhubarb | 3 | 14, 236 |
| Rhizophora mangle | Red Mangrove | 1 | 83 |
| Rhododendron dauricum | Chinese Alpenrose | 2 | 0 |
| Rhododendron ponticum | Pontic Alpenrose | 1 | 0 |
| Rhus copallina | Dwarf Sumac; Winged Sumac | 1 | 194 |
| Rhus coriaria | Sicilian Sumac; Sumac; Tanner's Sumac | 1 | 0 |
| Rhus glabra | Smooth Sumac | 1 | 34 |
| Rhus toxicodendron | Poison Ivy | 2 | 0 |
| Rhynchosia acuminatifolia | not available | 1 | 6 |
| Rhynchosia cabibaea | not available | 1 | 5 |