Side by side
Hornbeam or grey alder? How to tell them apart
Carpinus betulus · Alnus incana
How to tell them apart – hornbeam: leaf with many more parallel veins, pleated, and nutlets on winged bracts instead of cones; grey alder: alder with a pointed, double-toothed leaf that is grey and hairy underneath, and smooth, pale grey bark.
How do you recognise them?
- Hornbeam
- Sharply double-toothed leaf, pleated between the veins; grey, ‘muscular’ trunk.
- Compared with grey alder: leaf with many more parallel veins, pleated, and nutlets on winged bracts instead of cones.
- Grey alder
- Alder with a pointed, double-toothed leaf that is grey and hairy underneath, and smooth, pale grey bark.
| Hornbeam | Grey alder | |
|---|---|---|
| Leaves | Alternate, oval and pointed, 5–10 cm, sharply double-toothed, with 10–15 pairs of parallel veins between which the leaf is pleated. | Alternate, 5–10 cm, oval with a pointed tip, sharply double-toothed; underside grey-green and softly hairy. Not sticky. |
| Flowering | April–May | Hanging male catkins in February–March, before the leaves (February–March). |
| Fruit | Nutlets on a three-lobed wing, in hanging clusters. | Small woody cones 1–1.5 cm long, stalkless or short-stalked, in small clusters. |
| Bark | Grey and smooth, with twisting ridges as if there were muscles underneath. Buds pointed and pressed against the twig. | Smooth and pale grey, even on older trees; twigs hairy. |
| Shape and height | Broadleaf tree, 15–25 m, often as a hedge | Broadleaf tree, 10–20 m |
| Site | Sun to shade, any garden soil, normal | Sun or partial shade, any garden soil, dry to wet |
| Native to Belgium | Yes | No, naturalised |
| Good for bees, butterflies and birds | Yes, for butterflies and birds | – |
| Poisonous to people and pets | Not known to be poisonous | Not known to be poisonous |
| Pruning months | June–September and November–February | November–March |
What does it mean for your garden?
- Hornbeam is native: it feeds more insects and birds than a non-native species. If in doubt, choose this one.
- Hornbeam (15–25 m) and grey alder (10–20 m) both grow into large trees: too big for an ordinary garden, but fine in a large garden, a park or a meadow.
Read on
- Plant profile: Hornbeam
- Plant profile: Grey alder
- Hornbeam: when and how to prune
- Grey alder: when and how to prune
- Identification key
Also looks like
This comparison is compiled from the Bladwijzer species pages.