FIG 64. Rootstocks [rhizomes] or creeping subterranean branches of the Peppermint.
A rhizome is horizontally growing stem lying wholly or partly belowground, generally with short internodes and scale-like leaves, rooting at the nodes and with an upcurved apex which develops into an aerial shoot. Rhizomes are agents of vegetative reproduction.
FIG 64. Rootstocks [rhizomes] or creeping subterranean branches of the Peppermint. | |
The meaning overlaps with that of rootstalk which is a more general term for any sort of underground stem which gives rise to aerial shoots via lateral buds and/or from the growing tips (i.e., from an apical meristem). In some species the rootstocks are fleshy and function in food storage and survival over unfavourable seasons (Fig. 66, below). This term can also include short erect underground stems (Fig. 67 below).
FIG. 66. Rootstock of Solomon's Seal, with the bottom of the stalk of the season, and the bud for next year's growth. |  |
FIG. 67. The very short rootstock and bud of a Trillium or Birthroot. |  |