This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
稯 combines 禾 (grain) with 㚇, but the exact historical development and original meaning are uncertain.
The left side 禾 suggests grain or a plant, but the overall meaning is obscure. Picture a bundle of grain stalks tied together, as the kun reading たば (bundle) hints.
For ソウ, imagine tying a bundle of grain so tightly that it makes a 'sow' sound when you pull the string: sow -> ソウ.