NATIVE RANGE: North America

FIRST FINDING IN SLOVENIA: 1840

PATHWAYS: horticulture

POSSIBLE TO FIND: year-round

FLOWERING SEASON: May – October

DESCRIPTION: Up to 1.5 m tall, branched herbaceous perennials. Leaves are narrow lanceolate to ovate- lanceolate, with acuminate apex. Leaf margin entire or finely serrated. In some species, the leaf base has small lobes. Leaves and stem may be glabrous or pillose. On each stem there are several flower heads with yellow disc florets in the centre and white, purple or pink ray florets along the edge, depending on the species. Fruits are pillose or glabrous achenes bearing a pappus, which enables wind dispersion.

HABITAT: Ruderal sites, forest edges, scrubland, river banks, dykes and disused quarries.

STATUS: Widespread throughout Europe; in Slovenia widespread and common in the low-altitude regions. Also commonly cultivated in gardens. 

SIMILAR SPECIES: At least three alien aster species in Europe have purple ray florets. Smooth blue aster (S. laeve) has glabrous stems and appressed involucral bracts. New York aster (S. novi-belgii) has more ray florets and longer, spreading involucral bracts. New England aster (S. novae-angliae) is more pillose with a larger number of ray florets. All European native asters are much lower. White flowered asters are presented on pages at the descrition of Annual fleabane.

SOURCE: Field Guide to Invasive Alien Species in European Forests