Ontario Wildflowers website

Large-leaved Aster
Eurybia macrophylla
(formerly Aster macrophyllus)

Large-leaved Aster (Eurybia macrophylla) Other scientific names: Aster macrophyllus, Aster ianthinus, Aster multiformis, Aster nobilis, Aster riciniatus, Aster roscidus, Aster violaris

French names: Aster à grandes feuilles

Family: Composite Family (Asteraceae)

Group: Asters

Distinctive features: In forests. Large basal leaves. Colonies of basal leaves with no flower stems. Flat-topped flower head. Large flowers.

Similar species:
  •   Flat-topped White Aster (Doellingeria umbellata) - Leaves are lance-shaped.

  •   Heart-leaved Aster (Symphyotrichum cordifolium) - Basal leaves similar, but flowers are in a rounded panicle.


Flowers: Summer, Autumn;  White, Blue/Violet;  7 or more parts (petals);  2-4cm in diameter. Ray Flowers: 9-16, white, violet or lavender. Disc flowers: 20-40, yellow becoming purple. Flowers are in a flat-topped corymb, one to many flowers per plant.

Leaves: Alternate, Simple, Toothed;  Basal leaves very large, thick, rough, and somewhat heart-shaped (5-15cm), margins saw-toothed, upper and lower surfaces smooth or hairy/sticky. Upper stem leaves oval to lance-shaped, gradually smaller higher on the stem.

Height: Up to 1 m (1-2 ft)

Stem: Somewhat zig-zag in form. Stalks of the flower cluster have minute glands (need magnifying lens). Stem can be purplish sometimes.

Habitat: Forests;  Forests. Widespread throughout Ontario.

Grows in Sun/Shade: Shade

Lifespan: Perennial.  

Books: Newcomb's Wildflower Guide: 454    Peterson's Field Guide to Wildflowers: 354    ROM Field Guide to Wildflowers of Ontario: 166   

Native/Non-native: Native

Status: Common.

Notes: This Aster is found in forests in many areas. Its large basal leaves are distinctive, often forming large colonies without flowering stems. It's often one of the first asters to bloom.

Origin and Meaning of Names:
 Scientific Name: macrophylla: large-leaved


Photographs: 269 photographs available, of which 14 are featured on this page. SCROLL DOWN FOR PHOTOGRAPHS.

Range Map is at the bottom of the page

Large-leaved Aster (Eurybia macrophylla)

Large-leaved Aster.

Large-leaved Aster (Eurybia macrophylla)

Large-leaved Aster flowers.

Large-leaved Aster (Eurybia macrophylla)

The flowers can be almost white.

Large-leaved Aster (Eurybia macrophylla)

Large-leaved Aster (Eurybia macrophylla)

This photo also shows the rather loosely flat-topped aspect of the flower head.

Large-leaved Aster (Eurybia macrophylla)

The flowers are fairly open, almost ragged-looking.

Large-leaved Aster (Eurybia macrophylla)

Large-leaved Aster (Eurybia macrophylla)

Flower buds.

Large-leaved Aster (Eurybia macrophylla)

Flowers just opening in early September, making this plant a late bloomer.

Large-leaved Aster (Eurybia macrophylla)

The leaves are sometimes heart-shaped, leading to confusion with Heart-leaved Aster (Symphyotrichum cordifolium). The main differences are the size (Large-leaved Aster leaves are larger, hence the name), and the shape of the notch at the base of the leaf - in Heart-leaved Aster (Symphyotrichum cordifolium) this notch is much deeper and more curved.

Large-leaved Aster (Eurybia macrophylla)

A colony of Large-leaved Aster plants, without flower stems.

Large-leaved Aster (Eurybia macrophylla)

Large-leaved Aster (Eurybia macrophylla)

Only some of the plants in a patch will flower each year.

Large-leaved Aster (Eurybia macrophylla)

Large-leaved Asters often grow in large patches in shaded woods, like this one.


Range map for Large-leaved Aster (Eurybia macrophylla)

PLEASE NOTE: A coloured Province or State means this species occurs somewhere in that Province/State.
The entire Province/State is coloured, regardless of where in that Province/State it occurs.

(Range map provided courtesy of the USDA website and is displayed here in accordance with their Policies)