Compound Leaves (Palmate, Pinnate, Leaflet)

Compound vs. Simple Leaves

Leaves can be compound or simple. Here’s the difference:

Drawing courtesy of Judy Mason

Compound leaves are divided, made up of leaflets that are completely separate from each other.

On the other hand, simple leaves have a single leaf surface.

Types of Compound Leaves

Compound leaves generally come in two patterns, palmate and pinnate.

This one is palmate. Palmate leaflets connect to a central spot, like fingers to your palm.

California Buckeye – drawing © John Muir Laws

This one is pinnate. Pinnate leaflets connect along both sides of the leaf stalk, like quills on a feather.

Black Walnut – drawing © John Muir Laws

Tricky questions and answers

Is this leaf simple or compound?

Cut Leaf Geranium – Photo © Keir Morse

There are deep divisions in the leaf but the divisions don’t go all the way to the central vein or leaf stalk, so it doesn’t divide into completely separate leaflets. This is a simple leaf.

Is this leaf simple or compound?

American Vetch – Photo © Keir Morse

Each leaf grows from a bud on the stem. If we saw buds at the base of each leaf surface above, then we’d be looking at simple leaves connecting to a stem. However, since we see no buds here, the whole thing is a single leaf, making it a compound leaf.

Examples of Compound Leaves

Ferns have pinnate compound leaves.

Coastal Wood Fern – drawing courtesy Linda Bae Miller

This lupine has palmate compound leaves.

Arizona Lupine – photo © Keir Morse

Poison Hemlock leaves are twice pinnate, because each leaflet is divided into leaflets.

Poison Hemlock – drawing © John Muir Laws

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