What Is an Emarginate Leaf: A Notched Leaf Tip
An emarginate leaf has a small notch at its tip. NC State Extension lists the leaflets of five leaf akebia as emarginate, while NC State Extension contrasts emarginate with retuse in its list of leaf tips.
The short answer
An emarginate leaf has a tip notched inward at the midvein, toward the petiole. NC State Extension describes emarginate as a deep notch plus retuse as a rounded tip with a shallow notch. The leaflets of five leaf akebia show emarginate tips.
What does an emarginate tip look like?
The tip dips inward at the midvein, so the leaf appears nicked at the end.
| Apex | Shape | Source |
|---|---|---|
| Emarginate | Deep notch | NC State |
| Retuse | Rounded, shallow notch | NC State |
| Obtuse | Blunt angle | NC State |
| Acute | Sharp angle | NC State |
| Acuminate | Long, narrow point | NC State |
Source: NC State Extension.
Emarginate vs retuse
NC State notes retuse is a rounded apex with a shallow notch, while emarginate has a deeper notch.
Which plants show it?
NC State Extension lists five leaf akebia, a vine with 5 leaflets per leaf, as having emarginate leaflets.
How to: step by step
- Lay the leaf flat.
- Study the tip closely.
- Find the midvein.
- Check for a notch at its end.
- Gauge the notch depth.
- Compare with a retuse tip.
Troubleshooting
Notch hard to spot: use a hand lens. Look at several leaves.
Notch quite shallow: may be retuse. Compare charts.
Tip ripped: check other leaves. Use an intact leaf.
For more on leaves see cannabis leaf anatomy, cannabis nodes and internodes plus companion plants when growing marijuana. Kind Seed Co also stocks cannabis seeds.
Sources
- Akebia quinata, NC State Extension Gardener Plant Toolbox
- Extension Gardener Handbook, chapter 3: botany, NC State Extension
- Extension Gardener Handbook glossary, NC State Extension
- Tree and botanical glossary, Utah State University Extension Forestry
FAQ
What does emarginate mean?
NC State Extension defines an emarginate apex as a deep notch at the tip. The term describes the tip of the leaf, while other terms such as ovate or obovate describe the overall outline of the blade.
What is the difference between emarginate plus retuse tips?
NC State Extension defines retuse as a rounded apex with a shallow notch plus emarginate as a deep notch. Both have a dip at the tip, so the depth of the notch sets them apart. Compare several leaves, since notch depth varies a little on the same plant.
Which plants have emarginate leaves?
NC State Extension lists five leaf akebia as an example. Each leaf has 5 leaflets, 1 to 3 inches long, plus each leaflet is emarginate. The leaflets are bright blue green above.
Can leaflets be emarginate?
Yes. NC State Extension lists every leaflet on a five leaf akebia leaf as emarginate. NC State Extension notes a compound leaf has a blade divided into two or more leaflets, so describe the apex of each leaflet when naming the shape.
Why does the leaf tip matter?
NC State Extension notes leaves, especially the shapes of their blades plus margins, are useful in identifying species plus cultivars of plants. It lists apex shapes such as emarginate, retuse plus acute. Naming the tip along with the outline narrows down a plant in a key.
