millet
黍 refers specifically to millet, a type of grain.
黍 is a pictograph of a millet plant, with the top representing the grain head and the bottom the stalk and roots. The modern form retains this general plant-like structure.
The top part 秂 looks like a grain-heavy head of millet, and the bottom 氺 suggests the stalk and water it grows in. Together they form the millet plant.
For ショ, imagine a short millet stalk: short -> ショ, and the millet plant is compact and short.
(common) millet (Panicum miliaceum); proso millet
sorghum (Sorghum bicolor); Indian millet
corn; maize
Indian millet
corn (Zea mays)
sweet sorghum (Sorghum bicolor var. saccharatum)
glutinous millet; sticky millet
Johnson grass (Sorghum halepense); Johnsongrass; Egyptian millet
sorghum (Sorghum bicolor); Indian millet