Friesee lettuce is a variation of endive, also referred to as curly endive. This endive has an open head with curly, strongly shaped leaves. The heart of the lettuce is yellow with the outer leaves green. The outer leaves of a lettuce head of Friese tend to have a stronger bitterness than regular endive.
To store a full head of lettuce, wrap it in a damp paper towel and put the head inside a plastic bag. Store in the refrigerator. If you're storing individual lettuce leaves, spin them dry after washing and place them in a lettuce keeper in the fridge. A container is best to avoid bruising and bacteria buildup.
Store in the fridge in a sealed plastic bag, unwashed, until you're ready to use it.