TreesWild and cultivated

Alnus glutinosa

Alder

A familiar tree of Irish riverbanks, often carrying catkins alongside the previous season's little woody fruiting structures.

See all four seasons Explore fruits, seeds & edibility ↓ Where to look & how to find it ↓

Some plants are poisonous. Do not identify by a photograph alone, and never taste them.

FIELDCRAFT · FIND WITH CARE

Finding guide

Habitat first

Choose the season, find the habitat, then watch patiently. Search guidance is not a measure of rarity or conservation status.

When to go: Catkins in early spring, leaves in summer, woody fruit clusters in autumn and winter.
Where to start: Irish riverside paths and lakeshores. Stay on firm ground rather than entering wet banks.
What to do when you arrive: From firm banks, check rounded leaves and small woody cone-like structures, which can remain useful in winter. These are not conifer cones; stay off muddy margins.

Habitat and behaviour reference: Tree Council of Ireland ↗ · The practical steps are editorial advice based on the references, not live sightings.

ONE PLANT · FOUR SEASONS

One plant. Four seasons.

Look beyond the flowers: fresh leaves, fruits, bare stems and dormancy.

Meteorological seasons: spring March–May, summer June–August, autumn September–November and winter December–February. Irish weather, cultivar, pruning and plant age affect timing and appearance.

Photos illustrate the relevant feature, not the same plant photographed through a year in Ireland. Features shared across seasons, such as evergreen leaves, may use the same reference. Missing reliable photos are marked; dormancy is not death.

Spring

Mar–May

Flowers

Male catkins lengthen; new female structures coexist with last year's woody clusters.

Summer

Jun–Aug

Foliage and growth

Rounded green leaves expand as new female structures develop into green cone-like clusters.

Autumn

Sep–Nov

Fruits

Woody clusters darken as leaves fall, often without vivid red autumn foliage.

Winter

Dec–Feb

Bare branches or dry stems

Bare branches retain small woody fruiting clusters and next season's catkin buds.

Seasonal references: Tree Council of Ireland ↗ · Photo resized, converted to JPEG and stripped of metadata.

FRUIT · SEED · FOOD SAFETY

Fruits, seeds & edibility

Know the structure, then the part. Recognising a plant does not make it food.

Fruit

Female inflorescences become woody, cone-like structures containing tiny nutlets; they are not pine cones.

Food use of this part: Food safety not established by this guide

Seeds & dispersal units

Alder · Woody fruiting structures and nutlets; the seeds remain enclosed in the small fruits. — Woody fruiting structures and nutlets; the seeds remain enclosed in the small fruits.
Alnus_glutinosa_-_fruits_and_seeds.jpg: Bff derivative work: Bff · CC BY-SA 3.0 ↗ License terms

Seeds are enclosed in tiny nuts dispersed by water or wind; they are not pine nuts.

Food use of this part: Food safety not established by this guide

Some seed references show intact one-seeded fruits or dispersal units, as identified in their captions. A whole-fruit photo is not a close-up of the enclosed seed. Cones and arils are not true fruits of flowering plants.

Sources & limitations

Tree Council of Ireland ↗ · Botanical description, not proof of food safety
NC State Extension · Plant Toolbox ↗

No field detoxification methods or safe doses are provided. Never taste a plant to identify it or eat treated or contaminated specimens. Seek professional help after suspected accidental ingestion. National Poisons Information Centre, Ireland ↗

Photo resized, converted to JPEG and stripped of metadata.

BOTANICAL NOTESPlant notes

How to identify it

Rounded leaves often have notched tips. Long male catkins and small female structures that mature into woody, cone-like clusters; it is not a pine.

Where it grows

Riverbanks, lake edges, wet woods and damp plantings.

Growth and ecology

A deciduous tree with nitrogen-fixing root partners, suited to wet ground; water helps disperse its small seeds.

Flowering and seasons

Catkins in early spring, leaves in summer, woody fruit clusters in autumn and winter.

Where to look

Irish riverside paths and lakeshores. Stay on firm ground rather than entering wet banks.

Seasons vary with weather and location. Suggested habitats are places to look, not guaranteed sightings. Photos show only some features; check leaves, flowers, fruits and specialist references together.

Further reading:Tree Council of Ireland ↗

Photo license: AnRo0002 · CC0 ↗ · License terms ↗
Photo resized, converted to JPEG and stripped of metadata.

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