Lettuce (Lactuca sativa) - A popular salad green that
originated in western Asia.  Lettuce has been popular in
ancient cultures of the Greeks, Persians, and Romans.  
The five different types of lettuce include crisphead,
butterhead, cos, leaf, and stem.  In the United States the
crisphead is the most popular commercial type.  In the
home garden cos and leaf types are popular choices that
are easily grown in small spaces, while offering great
quality to salads and sandwiches.