noun
Refers to the main central support of a plant, from the base to the tip, including tree trunks and thick stems.
この木の幹はとても太い。
The trunk of this tree is very thick.
花の幹を切って花瓶に生けた。
I cut the flower's stem and put it in a vase.
noun
Specifically the long, straight body of an arrow, excluding the arrowhead and fletching.
矢の幹が折れてしまった。
The shaft of the arrow broke.
noun
Only when written 柄
Archaic term for the handle or grip of a tool or weapon. In modern Japanese, 柄 is usually read え or つか.
古文書には、刀の柄を「から」と記した例がある。
In old documents, there are examples where the handle of a sword is written as から.
茎 is the general word for plant stem, often thinner and more flexible than 幹, which implies a thicker, woodier main axis.
柄 read え is the modern common word for a tool handle or grip, replacing the archaic から reading.
The reading から is native Japanese, likely related to the core or main part of something. The kanji 幹 is used for its meaning 'tree trunk', while 柄 is an older assignment for 'handle' that has fallen out of use.