Here in my bioregion (Apennines, Central Italy) is not uncommon to see remains of ancient-style vineyards, while still in use ancient style vineyards are very rare (but they still exist). It is a kind of mixed cropping that was called Arbustum gallicum or Rumpotinetum in Latin and it is called Vite maritata (married grapevine) in Italian. It is a technology of Etruscan origin (ca. 700 BC) that has been used extensively in Italy until the 1960's. It consists in “marring” a grapevine (the bride) to a living tree (the groom) that supports the vine's growth.
The support tree for the Vine (Vitis Vinifera) was usually a Field Maple (Acer Campestre). The main reasons for choosing the maple were its long life, its shape (stocky and hard trunk), its good wood, and its capacity to stand very hard pruning (necessary to allow the sun to reach the sun-loving grapes). The couples were planted in rows and the vines were trained to grow along ropes tied between trees (Alberata). They were also planted in single stands (Piantata) with a grapevine or two growing on a single maple. Both rows and single stands were planted along or between wheat fields. It was what in permaculture language can be termed as the Maple-Grapevine-Wheat Guild (or the Acer – Vitis – Triticum guild, if you prefer).
Other variants which I have read about but never seen in my bioregion are the coupling of grapevine with Poplar (Populus), Elm (Ulmus Campestris), Oak (Quercus Robur), Robinia (Robinia Pseudoacacia), Common Ash (Fraxinus excelsior) and with several fruit trees as well.
For in-depth historical analysis see:
Sereni, Emilio, 1997 (Or. Ed. 1961), History of the Italian agricultural landscape, Princeton University Press, Google books. (Chapter 3)
Buono, Raffaele and Vallariello, Gioacchino, 2002, “La vite maritata in Campania”, Delpinoa, n.s. 44: 53-63. (Italian language)
For pictures google “vite maritata” or “piantata” or “alberata”.
I hope these tread may be of some interest (and it would be a pleasure to see the spreading of an Etruscan technology around the world).