Japanese name: レタス（タマチシャ） Scientific name:Lactuca sativa var. capitata
[Overview]
It is a biennial, but depending on the cultivation method it is also treated as an annual.
It is the heading group of chisha (Lactuca sativa).
It is divided into the crisphead type and the butterhead type; in Japan, what is called lettuce is the so-called crisphead type, while what is called salad-na corresponds to the butterhead type.
The crisphead type has hard, tightly heading leaves that are wrinkled, with notched margins, and a thick, crisp texture.
The butterhead type has loosely heading leaves with a smooth surface and unnotched margins, and a thin, soft texture.
