wild mulberry
柘 centers on a specific tree: the wild mulberry. The meaning is narrow and botanical, without broad abstract extensions.
柘 combines 木 (tree) with 石 (stone), likely as a phono-semantic compound where 石 hints at the sound and 木 gives the tree meaning. The exact historical development is uncertain.
A tree 木 that grows near stones 石, producing wild mulberry fruit. Picture a rugged stone hillside with a hardy mulberry tree.
For シャ, imagine a wild mulberry tree casting a large shadow (シャ) over the stones: shadow -> シャ, and the tree's shade covers the rocky ground.
pomegranate (Punica granatum)
Japanese box tree (Buxus microphylla var. japonica); Japanese boxwood
Chinese mulberry (Morus bombycis)
low door used in bathhouses to prevent the hot water from cooling (Edo period)
garnet
grossular; grossularite
andradite
grossular
pyrope
almandine
almandine