You can gather many useful items while on a hunt. Gathering points will vary by map and Quest, but an icon will appear over certain stalks of grass, mushrooms, and other objects to indicate where you can gather. Press Aボタン at these points to start gathering. When you've slain a monster, you can carve materials from it by pressing Aボタン.

Some gathering points require specific items. If you don't have that specific item in your item pouch, you won't be able to gather from those points.