barley, coix agretis
苢 is a rare kanji for specific grains: barley and coix agrestis (Job's tears). Its meaning is narrow and botanical, with no clear abstract center beyond these two grain plants.
苢 combines the grass radical 艹 with 㠯, which likely served as a phonetic component. The exact historical development is uncertain, and the character is rare.
The grass radical 艹 sits above 㠯, like a grain plant growing in a field. Picture barley and Job's tears sprouting from the ground.
For イ, imagine an ear of barley growing in a field: ear -> イ, and the ear of grain is the barley plant.