Data Views Exclude Ubiquitous Chemicals Activities: 12 Chemicals w/Activities: 1 All Chemicals: 1 CSV Excel PDF Show All Paginate Click on column headings to sort the list on the column # Activity Chemical Part All parts ... Stem Bark Low PPM High PPM StdDev *Reference 13 13 BETULIN Stem Bark -- -- Jim Duke's personal files. *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.