sprouts, tares
荑 centers on young plant growth: sprouts, shoots, and tares (weedy grasses). The idea is tender new vegetation emerging from the ground.
荑 combines the grass radical 艹 with 夷, which likely contributes a phonetic element. The exact historical development is uncertain, but the structure suggests a plant-related character.
The grass top 艹 sits above 夷, which looks like a person with a bow. Picture a field where sprouts and tares shoot up around an archer's feet.
For テイ, imagine a tea plant sprouting: tea -> テイ, and the young leaves are the sprouts.