This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
The historical origin of 樃 is uncertain. It visually combines 桹 and 月, but the component relationship is unclear.
Since the meaning is unclear, focus on the shape: a tree 木 beside 桹 and 月. Picture a moonlit tree with a distinctive name, but remember its meaning is uncertain.
For ロウ, imagine a low-hanging moon beside the tree: low -> ロウ, and the moon 月 is right there in the character.
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