There are seven main types of lettuce, including cos or romaine, butterhead, leaf, stalk, crisphead, latin, and oilseed.

Bolting is when an edible plant, like lettuce, develops a flowering stalk and begins producing ... "I like to grill romaine when it does that," says Irish-Hanson.

An undergraduate mechanical engineering team developed a motorized Romaine lettuce trimmer. As it rotates, the system accepts a head of lettuce, softly grasps it, positions the stalk for automated ...