Data Views Total Plants: 3 CSV Excel PDF Click on column headings to sort table by that column Plant Part All Plant Rhizome Root Low PPM High PPM StdDev *Reference Piper methysticum Root -- 22.0 * Piper methysticum Plant -- -- * Piper methysticum Rhizome -- -- * *Unless otherwise noted all references are to Duke, James A. 1992. Handbook of phytochemical constituents of GRAS herbs and other economic plants. Boca Raton, FL. CRC Press.