What is Cavallo greens?

It belongs to the lettuce family.

It is a variety of lamb's lettuce.Here is a detailed article.

Lamb's Lettuce, corn salad, field lettuce, fetticus, lamb's tongues

Mâche (French)

(Valerianella locusta or V. olitoria -- Family Valerianaceae)

Lamb's lettuce is an undemanding herb that is widely distributed in Europe and Asia, and has been cultivated only since the beginning of the 20th century. Originating in the temperate zones of Europe, it was first described in 1699 in an English diary. It was once a common cold-weather salad leaf in the US, and all but disappeared before being resurrected by Americans travelling in Europe. It is now exported from France, the Netherlands, Belgium, and Germany, and, once again, becoming popular with small-scale growers in the US.

Depending on which authority is quoted, the name originated because lambs were partial to it or because it appeared during lambing season. Another name, corn salad, comes from its regular appearance as a cornfield weed. Mâche is a word seen in specialty groceries and on menus. Chefs prefer to use the French name because, they say, if "corn salad" is used, the clientelle expects just that -- a salad made from corn. It has been popular for centuries in France; but, in England, it declined in popularity in the 1700s, and by the 19th century, declared a noxious weed.

The leaves are a good source of beta carotene, Vitamin C, and folate. In spite of its delicate appearance, lamb's lettuce is an extremely hardy plant and particularly valued as a nutritious winter salad crop. The leaves are a bright green and rounded with a slightly nutty taste, and is usually eaten raw as a salad green. Before the appearance of winter lettuce varieties, lamb's lettuce was the main winter salad green and at one time, classified in the same genus. There are two forms: the large or broad-leaved and the darker, more compact, green type which is popular in western Europe, but less productive. It is often planted in the unused damp spaces of gardens or flower beds, and makes the ideal cover between taller crops. Some varieties include Cavallo, Elan, Jade, Large Leaved, Grote Noordhollandse, Verte de Cambrai, Verte d'Etampes, Vit, and Volhart.

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