In my Umbria cookbook, Julia della Croce emphatically states that spelt is an incorrect translation of farro; it's emmer wheat, she says. So, I followed Adam's link with interest. According to Abundantlifeseed.org, she's only partially correct:
The grains were "farro" yes? Mostly it is translated as spelt, but that is only partially true. Farro is a term which covers a number of species of primative wheat. One of these is spelt, but the one that is more commonly used in soup, salads and risotto (I have had an excellent version of this at La delphina) is Farro Medio. This is an ancestor of modern hard wheats used in pasta making.
Altgolt Spelt (COG) T. spelta the German wheat of colonial America, was once the principal wheat in Europe. Treat as winter wheat. Grows in thick clumps and difficult to thresh. Heirloom, Rare.
Black Einkorn (COG) T. monococcom a beautiful form of domesticated wheat, disease resistant and tolerates poor soil, but low yields. Small headed, small seeded wheat with 2 rows and black highlights on the husks and awns. Grows wild in Near East and grown as relic crop in Turkey. Delicate and very striking in flower arrangements. Does not thresh easily. Rare. BULK
Emmer (COG) T. dicoccum spring variety, durum type, tall, large seeded, 4 row with big chestnut brown heads and thick straw. Also good for weaving. An impressive grainĖincredible in the garden. Heirloom. BULK