A scallion, is an edible plant the genus Allium. The upper green portion is hollow. It lacks a fully developed root bulb. Harvested for their taste, they are milder than most onions. They may be cooked or used raw, as a part of salads or Asian recipes. Diced scallions are used in soup, noodle and seafood dishes. To make many Eastern sauces, the bottom quarter-inch of scallions are commonly removed before use.