Pop Green

Pop Greens (ポップ グリーン, Poppu Gurīn) are the seeds of hostile plants that possess instantaneous growth. They exist in the Grand Line, on the Boin Archipelago in the forest of "Greenstone", they are present in abundant numbers on this island. These seeds have various uses.

History
Heracles uses these seeds as bullets and weapons. According to Heracles, they have various uses. Heracles is teaching Usopp how they work since Usopp decided to become stronger.