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Species21 December 2025 5 min

American skunk cabbage: the yellow flag of a wet woodland in trouble

Lysichiton americanus — banned from sale since 2016, still spreading through Welsh and West Country wet woodland.

American skunk cabbage produces vivid yellow spathes in March and April that look almost ornamental. They are also the marker of a wet woodland whose native flora is being quietly displaced.

Where we find it

Wet woodland flushes and stream margins in upland Wales, the West Country and parts of Scotland. The plant escapes from garden ponds and follows watercourses downstream into nature reserves it should never have reached.

Removal

Crown excavation in November to February when the plant is dormant and the ground is firm. Any rhizome left behind regrows; biosecure tooling between sites is essential to prevent moving viable fragments to clean ground.

Reviewed by

The survey team

PCA-certificated surveyors, Japanese Knotweed Elimination

PA1 / PA6A certificated surveyors who carry out the site visits, write the management plans and sign off the reports issued to lenders and solicitors.

Reviews the technical, legal and lender statements in this article.

What this page can't tell you

  • Guidance is general. Identification, treatment choice and timescales can only be confirmed by a site visit — photographs alone are indicative.
  • Lender and insurer requirements vary by institution and change over time. We state what is typically accepted, not what any named lender will accept on your case.
  • Guarantee (IBG) eligibility depends on the plan chosen, the survey findings and the underwriter's acceptance. It is not automatic.
  • Legal points summarise published law and guidance current at the review date. They are not legal advice.

Last reviewed · Questions on anything stated here: 07582 869979

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