An official website of the United States government.
| Chemical Name | Dosage | Reference |
|---|---|---|
| YATRORICINE | not available | Duke, 1992 * |
| ZYGOPHYLLIN | not available | Duke, 1992 * |
| Plant Name | Common Name | Chemical Count | Total Parts Per Million |
|---|---|---|---|
| Ravensara aromatica | Ravensara | 2 | 234 |
| Rheum officinale | Chinese Rhubarb | 5 | 25.700000762939453 |
| Rheum palmatum | Chinese Rhubarb | 4 | 0.5 |
| Rheum rhabarbarum | Rhubarb | 5 | 117 |
| Rhododendron dauricum | Chinese Alpenrose | 6 | 0 |
| Rhododendron ferrugineum | Rusty-Leaved Alpenrose | 1 | 0 |
| Rhododendron ponticum | Pontic Alpenrose | 3 | 0 |
| Rhus coriaria | Sicilian Sumac; Sumac; Tanner's Sumac | 3 | 0 |
| Rhus toxicodendron | Poison Ivy | 2 | 0 |
| Rhynchosia minima | Burn Mouth Vine | 1 | 0 |
| Ribes nigrum | Black Currant | 10 | 123, 102 |
| Ribes rubrum | Red Currant; White Currant | 1 | 3, 488 |
| Ribes uva-crispa | Gooseberry | 5 | 4, 204 |
| Ricinus communis | Castorbean | 7 | 0 |
| Robinia pseudoacacia | Black Locust | 2 | 33, 250 |
| Rosa canina | Rose; Dogbrier; Dog Rose | 8 | 150 |
| Rosa centifolia | Cabbage Rose | 3 | 0 |
| Rosa damascena | Damask Rose | 5 | 15, 000 |
| Rosa gallica | French Rose | 3 | 4 |
| Rosa multiflora | Multiflora Rose | 5 | 0 |