| Plant | Low PPM | High PPM | StdDev | *Reference | |
|---|---|---|---|---|---|
| Pinus sylvestris | Root | -- | -- | * | |
| Leonotis leonurus | Se | -- | -- | Pedro, L.G., Barroso, J.G., Marques, N.T., Ascensao, L., Pais, M.S.S. and Scheffer, J.J.C. 1991. Composition of the Essential Oil from Sepals of Leonotis leonurus R. Br. J. Ess. Oil Res. 3: 451-3 | |
| Cypripedium pubescens | Root | -- | -- | * | |
| Rheum rhabarbarum | Root | -- | -- | * | |
| Paeonia lactiflora | Root | -- | -- | Chemical Constituents of Oriental Herbs (3 diff. books) | |
| Houttuynia cordata | Shoot | -- | -- | * | |
| Tagetes minuta | Shoot Essent. Oil | -- | -- | * | |
| Coriandrum sativum | Seed | -- | -- | * | |
| Angelica sinensis | Shoot | -- | -- | Jim Duke's personal files. | |
| Angelica sinensis | Tissue Culture | -- | -- | Jim Duke's personal files. | |
| Anaphalis margaritacea | Plant | -- | -- | * | |
| Panax quinquefolius | Root | -- | -- | * | |
| Cassia marilandica | Plant | -- | -- | * | |
| Mentha arvensis var. piperascens | Plant | -- | -- | Duke, J. A. Writeups or information summaries on approximately 2,000 economic plants, USDA, ARS, Beltsville, MD 20705. | |
| Ocimum basilicum | Shoot | -- | -- | * | |
| Cinnamomum verum | Stem Bark | -- | -- | * | |
| Cinnamomum verum | Root Bark | -- | -- | * | |
| Myroxylon balsamum | Gum | -- | -- | * | |
| Fragaria spp | Plant | -- | -- | * | |
| Juniperus communis | Leaf | -- | -- | * |