And the answer is...

     Yesterday I asked you to correctly name the vegetable that is only consumed raw, never canned or frozen.  The answer comes from the University of Illinois Extension Service:

     "Due to the extremely high water content, 94.9%, there are no successful method(s) of long-term preservation of lettuce.  Lettuce does not respond well to freezing, canning or drying.  For optimal nutritional value, lettuce should be eaten while it is fresh and crisp."

     So there you have it.  But what do you really know about this so called "rabbit food" that we can enjoy year round?  Let's take a look at its history and see if we can uncover some interesting facts about this quintessential vegetable.
     Lettuce is a temperate annual or biennial plant belonging to the sunflower family under the nomenclature  Asteraceae.  It was first grown by the Egyptians and eventually made its way to the Greeks and Romans.  The Romans gave it the Latin name "lactuca" meaning milk, due to the white substance that is produced when the stem is cut.  They also were the first to incorporate it into the meal, with other greens, as a first course.  It was thought alternately by those cultures to be an aid in fertility or a cause of sterility.
     As anyone who has grown a backyard garden knows, it is a hardy annual and is easily cultivated in the early Spring and grows best in the cooler weather before the heat of Summer.  Warm temperatures cause it to "bolt" or go to flower and eventually to seed too rapidly.  It is a good source of Vitamin A and K and also potassium.  There are between 65 and 140 distinct varieties and a general rule of thumb (a green thumb, if you will) is that the darker the leaf of a particular variety the more nutritious it is.  That being said, it is a fact that the pale iceberg lettuce that is most commonly sold in our super markets is the least healthful of all the varieties available.  World production of lettuce and it's relative, chicory, reached an impressive 23.62 tons in 2010, over half of that coming from China.
     Lettuce has a mild narcotic effect when consumed.  No wonder Peter Rabbit after eating the lettuce in Farmer MacGregor's garden felt so soporific.  And that also may account for the Anglo-Saxon term "sleepwort" when referring to it.
     One word of caution, however.  Lettuce should always be thoroughly rinsed before eating.  It can transmit certain serious diseases including E. coli, salmonella, listeria and shigella when grown in contaminated soil.  Isn't that correct, Rudi?