Data Views Total Plants: 21 CSV Excel PDF , Previous12 Show all rows. Paginate rows. Click on column headings to sort table by that column Plant Part All Essential Oil Flower Leaf Plant Rhizome Root Essent. Oil Shoot Low PPM High PPM StdDev *Reference Thymus mastichina Plant -- 30.0 -0.9 Lawrence, B.M., Essential Oils 1976-1977, Essential Oils 1978, Essential Oils 1979-1980. *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.