Florapass
English
Aleutian ragwort

Aleutian ragwort

Jacobaea cannabifolia

Identify the Aleutian ragwort from a photo and log your finds with Florapass.

Coming soon to the App Store and Google Play.

How common: Fairly rare

Invasive alien species – remove it if you can

Aleutian ragwort is a tall, long‑lived plant with bright yellow, daisy‑like flower heads and leaves cut into 3–7 long “fingers” that recall hemp. Native to East Asia and reaching the far west of Alaska, it has escaped from gardens in parts of Europe. It favours moist, nutrient‑rich edges, ditches and waste ground. Poisonous and regarded as harmful in several Nordic countries.

Did you know?

  • Listed as a nationally harmful invasive alien in Finland.
  • Its Latin name means “hemp‑leaved”, referring to the hand‑shaped leaves.

About the species

Identification

Robust perennial, usually 0.5–2 m tall. Upright stem, smooth or only slightly hairy. Leaves dark green and large (about 10–20 cm), placed one by one up the stem, each deeply cut into 3–7 narrow lobes like fingers; edges toothed. The top carries many small yellow, daisy‑like heads in loose clusters. After flowering it makes small hard seeds with silky hairs that aid wind spread. Key clues: very tall size and the big hemp‑like leaves. Park ragwort is also tall but has large uncut leaves; the common smaller ragworts have much smaller, differently divided leaves. Flowers in Finland from July to September.

Plant group

Herbaceous plants

Habitat

herb-rich forest, yards and roadsides

Toxicity

A poisonous plant – do not taste it. Source: HUS Poison Information Centre (Finland), tel. 0800 147 111.

Flowering

Jul–Sep

About the habitat

Grows on moist, nutrient‑rich ground: forest edges, river and ditch banks, roadsides, allotments and waste places. Spreads by wind‑borne seeds and also by creeping shoots. Local in southern Finland, especially around Helsinki and Turku (Ruissalo), with scattered records elsewhere; an established garden escape that is spreading.

Sources

Photo: Ольга Зеленова, CC0 1.0 https://www.gbif.org/occurrence/6413641439

Text: Pinkka: IPS-177 Fennoscandian flora - Hippophaë-Lythrum, CC BY 4.0 https://laji.fi/taxon/MX.42599

Text: FinBIF species descriptions, CC BY 4.0 https://laji.fi/taxon/MX.42599

Text: Wikipedia (Finnish), CC BY-SA 4.0 https://fi.wikipedia.org/wiki/Hamppuvillakko

See also