Microscopic T.S. shows the periderm composed of five to nine layers of cork, followed by a layer of phellogen, and a few layers of phelloderm of rectangular cork cells; a cortex composed of thin-walled parenchymatous cells, irregular in shape with intercellular spaces, containing abundant starch grains; numerous oleo-resin cells filled with oil globules are present, which, in mature roots may degenerate and form irregular cavities. The vascular region and cortex are traversed by biseriate medullary rays, containing circular starch grains, usually measuring up to 24 ΅, but some up to 65 ΅ in length and 45 ΅ in breadth. The phloem is a wide zone composed of sieve tubes, companion cells, phloem parenchyma, and medullary rays. Schizogenous oleo-resin cells lined by epithelium containing yellowish brown substances are present in this zone. The cambium is very distinct, consisting of four to eight layers. The xylem consists of vessels and tracheids. Powder - Creamish yellow; shows under a microscope, drum-shaped vessels with reticulate thickenings, tracheids elongated with pointed ends having reticulate thickenings; fibers narrow and elongated with pointed ends; circular starch grains present.

Powder: Creamish yellow; shows under a microscope, drum-shaped vessels with reticulate thickenings, tracheids elongated with pointed ends, having reticulate thickenings; elongated narrow fibers with pointed ends; and circular starch grains present.