root of a moso bamboo
Refers specifically to the root of the moso bamboo (孟宗竹). Often used in contexts discussing bamboo shoots or bamboo cultivation.
See also: もうそうちく
A new bamboo shoot has sprouted from the root of the moso bamboo.
Compound of 孟宗 (moso, from the name of a Chinese filial son associated with bamboo) + の (possessive particle) + 節 (node/joint/root). The exact historical derivation is uncertain, but the term is conventionally associated with the root of the moso bamboo.