Purdue Arboretum botanical terminology reference and learning database.
Palmate Having leaflets or other parts radiating from a common point, like outstretched fingers from a palm. Did you know? Maple leaves are palmate, with lobes spreading from one point like fingers from a hand.
Perfoliate Describes a leaf that completely surrounds the stem. Botanists use this feature to describe leaf shape, surface, edge, or arrangement, which helps with plant identification.
Petiole Leaf-stalk. Botanists use this feature to describe leaf shape, surface, edge, or arrangement, which helps with plant identification. Did you know? The petiole helps position the leaf blade so it can capture light efficiently without shading nearby leaves.
Pinna A single leaflet of a pinnately divided (feather-like) leaf. Botanists use this feature to describe leaf shape, surface, edge, or arrangement, which helps with plant identification.
Pinnate Having parts arranged like a feather, symmetrically on either side of a central rib - often used to describe compound leaves. Did you know? Ash, walnut, hickory, and rose leaves are pinnate, with leaflets arranged along a central stalk.
The Purdue Arboretum is a collaboration between the Department of Horticulture and Landscape Architecture and Administrative Operations