to cut grass, hay, fodder
蒭 centers on cutting grass and the resulting material: hay or fodder. The meanings are closely linked as the action and its product.
蒭 combines the grass radical 艹 with 芻, which likely contributes both sound and the idea of cutting grass or fodder. The exact historical development is uncertain.
The top 艹 is grass, and the bottom 芻 looks like a bundle of cut grass being gathered. Picture a scythe cutting grass and the cut stalks being tied into hay.
For シュウ, imagine a shoe filled with freshly cut hay: shoe -> シュウ, and the hay is used as fodder.
bhikkhu (fully ordained Buddhist monk)