Jeanne briefly describes the cultivation history and botany of Brassica rapa, B. napus, B. nigra, and B. juncea to round out our cursory tour of the extraordinary genus Brassica. Michelle offers a recipe highlighting a vegetable likely present at the first Thanksgiving: the turnip, an exceptional cultivar of B. rapa.
White Tokyo turnips and purple-top turnips
Along with the turkey, stuffing, potatoes, green beans and cranberry sauce, Brussels sprouts have become something of a Thanksgiving staple. None of these dishes, however, were part of the original harvest feast shared by the Pilgrims and Wampanoag in Plymouth Colony in 1621. A close relative of Brussels sprouts, however, likely had an honored place at the table: turnips. The Pilgrims chose the tuberous vegetable to occupy precious cargo space in the holds of their ships bound for the New world and grew them in their Plymouth Colony gardens. Turnips were probably also on most Americans’ Thanksgiving menus when President Lincoln made the holiday official in 1863. During that first Thanksgiving turnips served as a sole representative of a genus, Brassica, that has one of the most impressive radiations of cultivated species on the planet. Its extensive domestication happened primarily in Europe and Asia. While Native Americans may have exploited weedy little native species in same family as the now-familiar Brassica (the mustard family, Brassicaceae), there is little evidence that they cultivated them or subjected them to artificial selection.
Row of turnips in the Monticello garden
Descriptions of turnips date to Alexander the Great’s vast kingdom, which spanned much of central Eurasia. The vegetable’s domestication history earlier than that is not well known, but turnips likely made their way to western Europe from an Asian origin, along with several other well-known varietals of the same species, Brassica rapa. In a previous post we discussed the numerous varieties of Brassica oleracea (including kale, collard greens, Chinese broccoli, Brussels sprouts, kohlrabi, cabbage, broccoli, and cauliflower). The radiation of Brassica rapa into several morphologically variable domesticated vegetables across its broad native range in Europe, Asia and North Africa is almost as spectacular as that of B. oleracea. Turnips, Italian rapini, and Asian cultivars bok choy, tatsoi, mizuna greens, napa cabbage, and purple mustard greens are all varieties of B. rapa. In addition to B. oleracea and B. rapa, other important Brassica species in the human diet are Brassica napus (rutabaga and oilseed), Brassica nigra (black mustard) and Brassica juncea (mustard greens). As such, the single genus Brassica alone accounts for a respectable fraction of the vegetables in a well-stocked produce section. Continue reading