Leaf shapes

The following is a defined list of terms which are used to describe leaf morphology in the description and taxonomy of plants. Leaves may be simple (a single leaf blade or lamina) or compound (with several leaflets). The edge of the leaf may be regular or irregular, may be smooth or bearing hair, bristles or spines. For more terms describing other aspects of leaves besides their overall morphology see the leaf article.

Leaves of most plants include a flat structure called the blade or lamina, but not all leaves are flat, some are cylindrical. Leaves may be simple, with a single leaf blade, or compound, with several leaflets. In flowering plants, as well as the blade of the leaf, there may be a petiole and stipules; compound leaves may have a rachis supporting the leaflets. Leaf structure is described by several terms that include:

Being one of the more visible features, leaf shape is commonly used for plant identification. (Similar terms are used for other plant parts, such as tepals)

Leaf margins are frequently used in visual plant identification due to the fact that they are usually consistent within a species or group of species, the leaf edges are also an easy to observe characteristic which makes them even more useful for identification. Edge and margin are both interchangeable in the sense that they refer to the outside perimeter of a leaf.

Leaves may also be folded or rolled in various ways. The folding of leaves within a bud is vernation, is the folding of an individual leaf in a bud.

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