From Halopedia, the Halo wiki
Lettuce (Lactuca sativa) is an annual plant of the family Asteraceae often grown as a leaf vegetable. Native to Earth, its leaves are edible. First cultivated by the ancient Egyptians, Lettuce has since spread throughout the world. Lettuce has a variety of culinary and herbal uses, most commonly eaten in salads or as a part of sandwiches and wraps. It is a hardy vegetable that may easily be grown in temperate environments, although it may suffer from fungal or bacterial diseases as well as several pests. Lettuce is a rich source of vitamins K and A as well as a moderate source of folate and iron.
By the twenty-sixth century, Lettuce is still grown and consumed by humans. In 2552, Jersey Morelli ordered a burrito that contained lettuce. Lettuce was also among the provisions kept by Luther Mann during his time on Zeta Halo; he often fed some of it to a small deer-like animal, which he named "Vanessa", that came to his campsite each morning. In 2558, Cdr. Maya Sankar of the Office of Naval Intelligence commented on Mshak Moradi's fighting ability by noting that his resolve was only about as sturdy as a piece of lettuce. Lettuce is also known to be grown on Cascade, with "technoartisinal" greenleaf lettuce grown there being an important part of the burgers served by the restaurant Have S'Moa on Gannick 22.
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