| Plant | Low PPM | High PPM | StdDev | *Reference | |
|---|---|---|---|---|---|
| Mentha x piperita | Leaf | 0.01 | 0.1 | -0.9 | Duke, J. A. Writeups or information summaries on approximately 2,000 economic plants, USDA, ARS, Beltsville, MD 20705. |
| Vaccinium myrtillus | Fruit Juice | -- | 0.08 | * | |
| Vaccinium corymbosum | Fruit Juice | 0.01 | 0.08 | * | |
| Morinda citrifolia | Fruit | -- | 0.02 | -0.7 | * |
| Carica papaya | Fruit | -- | -- | -0.7 | Jim Duke's personal files. |
| Juglans nigra | Fruit | -- | -- | * | |
| Vanilla planifolia | Fruit | -- | -- | * | |
| Cinnamomum verum | Bark | -- | -- | Lawrence, B.M., Essential Oils 1976-1977, Essential Oils 1978, Essential Oils 1979-1980. | |
| Hyssopus officinalis | Essential Oil | -- | -- | * | |
| Cinnamomum verum | Root Bark | -- | -- | * | |
| Tanacetum parthenium | Fruit Essent. Oil | -- | -- | * | |
| Polianthes tuberosa | Flower | -- | -- | * | |
| Ligustrum japonicum | Flower | -- | -- | * | |
| Aspalathus linearis | Leaf Essent. Oil | -- | -- | * | |
| Albizia lebbeck | Flower | -- | -- | Wealth of India. | |
| Pueraria montana | Fruit Essent. Oil | -- | -- | * | |
| Glycyrrhiza glabra | Rhizome Essent. Oil | -- | -- | * | |
| Hibiscus sabdariffa | Fruit | -- | -- | Chemical Constituents of Oriental Herbs (3 diff. books) | |
| Hibiscus sabdariffa | Leaf | -- | -- | Chemical Constituents of Oriental Herbs (3 diff. books) | |
| Robinia pseudoacacia | Flower | -- | -- | * |