How do you recognise Common alder (Alnus glutinosa)?

Leaf

Liliane Roubaudi, Tela Botanica · CC BY-SA 2.0

Common alder

Alnus glutinosa (L.) Gaertn.

Also known as: Alder, Black alder

Family: Betulaceae

20 to 25 m tall

Riverbanks, wetlands and marshy areas

Flowering: February – March, before the leaves

Part shade

Full sun

-30°C

❓ How do you recognise this plant?

Its small, woody female cones look like tiny conifer cones and persist on the tree. Green alder remains a low, bushy shrub of mountain slopes, with pointed, glossy leaves, whereas common alder is a large riverbank tree with rounded leaves that feel slightly sticky to the touch.

🍃 Leaves

Rounded to ovate, often truncated or notched at the tip; young leaves sometimes sticky.

🌸 Flowers

Long hanging male catkins and small reddish female catkins

🍎 Fruits

Small brown woody cones persisting all winter

🪵 Bark

Brown-black, cracking into small plates

🗺️ Distribution

Europe, North Africa, western Asia; very common in France along watercourses and in wetlands

🐝 Value for pollinators

Early male catkins, from February, providing an important source of pollen for bees in late winter

✂️ Horticultural uses

Planted on riverbanks to stabilise soils, also used in wetland restoration

⚠️ Possible toxicity

No known toxicity

⚠️ Look-alike species

Common alder

Alnus glutinosa

Green alder

Alnus viridis

Green alder remains a low, bushy shrub of mountain slopes, with pointed, glossy leaves, whereas common alder is a large riverbank tree with rounded leaves that feel slightly sticky to the touch.

🌿 Other Betulaceae to discover

European hop-hornbeam

Ostrya carpinifolia

ℹ️ Educational profile — do not use it to judge whether a plant is edible or safe.

🌱 This database is constantly evolving — species and information are added and corrected regularly. Spotted a mistake? Report it below.