Ampelography: What Leaves Can Tell Us

Working in the vineyard for 5 years now has brought us up close and personal with our grape varieties. Recently, while we were doing some leaf pulling, my husband came to show me a shoot that he had cut off and said, "What do you think this is?" I immediately recognized that it was a Cabernet Sauvignon with a bunch of grapes on it and thought, "Why did you cut off that shoot?" Then my husband said, "Where do you think I found it?" It was in the row with all of our Auxerrois grapes, a white variety. He took me there to show me the vine and the difference was obvious. The leaves and the grape habit was totally different between the Cabernet Sauvignon and the Auxerrois. Knowing this difference is part of ampelography: (ἄμπελος, "vine" + γράφος, "writing") the field of botany concerned with the identification and classification of grapevines.

Every part of the grape leaf has a name:¹

For the mature leaf, the following descriptors and attributes are associated with the various leaf parts:²

Descriptor	Attributes
Hair	· type – bristles or woolly · amount – none to felty
Lobe Number	· entire or with 3,5, or more lobes
Teeth - Size and Shape	· convex (arched), pointed or concave
Petiolar Sinus	· shape – V, lyre or a u · width – open,close or overlapping · naked, ie delineated by the vein – e.g. chardonnay
Leaf Shape	· circular, reniform, wedge shaped (cuneiform) or pentagonal
Leaf Color	· light, dark
Leaf Surface	· rough or “bullate”, or smooth
Petiole and Vein Color	· green, red/green, red
Leaf Contour	· flat, lacy, cupped
Lateral Sinuses	· depth and shape, presence of tooth, e.g. Cabernet Sauvignon, Nebbiolo

References:
1. Viticulture Online Course, 5891, Grapevine Structure and Function.
2. Libby Tassie, Vine identification – knowing what you have, Australian Government, Grape and Wine Research and Development Corporation, Fact Sheet August 2010.