Forest Preserve District of Cook County, Illinois
Nature Bulletins
Newton Home Page

Introduction and Instructions

Search Engine

Table of Contents



Lettuce and Its Relatives
Nature Bulletin No. 409-A   March 6, 1971
Forest Preserve District of Cook County
George W. Dunne, President
Roland F. Eisenbeis, Supt. of Conservation

The lettuce grown in our home gardens and on vast acreages of truck farms so that we may enjoy it in salads, is proof that, in the plant kingdom, you can "make a silk purse out of a sow's ear. .

It's ancestor is a tall spindly pesky weed which originally grew along the north shore of the Mediterranean and far into Asia: the Prickly Lettuce which has become widespread in this country and temperate regions over most of the world. It is closely related to about 40 bothersome foreign weeds found now in the Chicago region: several more kinds of wild lettuces, Chicory, the Dandelions, the Sow Thistles, the Rattlesnake Roots, and the Hawkweeds which include the Devil 's Paintbrush.

Lettuce and its relatives are members of the Chicory Family which belongs to the immense group of Composites. This family differs in having blossoms that are disks of strap-shaped flowers without any central disk of tubular flowers. All have a bitter milky juice which, in the wild lettuces, has such narcotic and sedative properties that one is called "Wild Opium". Lettuce has been cultivated more than 2000 years. It is said to have been served on the tables of a Persian king in 400 B.C. and is mentioned by Theophrastus, the pupil of Aristotle who was the pupil of Plato who was the pupil of Socrates.

There are hundreds of varieties and strains of tame lettuce ranging from those that have a few upright narrow smooth leaves (and which soon shoot up a seed stalk), to whose with many broad leaves which may be smooth or may be crinkled, and which may be merely clustered ("leaf" lettuce) or may overlap to form dense heads like cabbage. A leaf lettuce or a head lettuce may be either of two principal types: "Butter" varieties with pliable leaves having a "buttery" flavor (such as the "Limestone" or "Bibb" lettuce), and "Crisp" varieties with leaves that are more tender and brittle. The "Cos" varieties, a third type, are much preferred in England and seldom grown in this country because, unlike most lettuce, they do best in cloudy weather. Our varieties do best in spring -- or sometimes in early autumn -- if sown in a sandy loam kept rich by applications of fertilizers, and receive plenty of sunshine. Chemically, they are all the same: about 98 percent water with small amounts of cellulose, sugar, protein, mineral salts and vitamins -- especially Vitamin A.

Endive, another relative which is a close cousin to Chicory, is a native of India but was cultivated by the early Egyptians and Greeks. It has a more bitter taste than lettuce but is preferred in some salads by connoisseurs. Like chicory and most members of this plant family, its purple flowers (sometimes white) open early in the morning and are usually closed by noontime. Chicory is the European weed, with beautiful sky-blue flowers, that has become so common here in fields and along our roadsides. Its roots are used as flavoring or as a substitute for coffee. Its small leaves can be used in salads when young and tender.

You know about our common dandelion. Its young leaves are picked for "greens " and the root, which may be used as a poor substitute for coffee, has medicinal value. You may not know about Salsify or Oyster Plant -- one of the Goatsbeards. A native of Europe, it has long grass- like leaves and used to be planted here in vegetable gardens because the root, when cooked, tastes something like an oyster, Now it grows wild because the dull purplish flowers are followed by seeds with little parachutes of down which are wind-borne like those of the dandelion and many other members of the Chicory Family.

To return to the Nature Bulletins Click Here!
Hosted by NEWTON

NEWTON is an electronic community for Science, Math, and Computer Science K-12 Educators, sponsored and operated by Argonne National Laboratory's Educational Programs, Andrew Skipor, Ph.D., Head of Educational Programs.

For assistance with NEWTON contact a System Operator (, or at Argonne's Educational Programs

Educational Programs
Building 360
9700 S. Cass Ave.
Argonne, Illinois
60439-4845, USA
Update: June 2012
Sponsered by Argonne National Labs