Poisonous Plant Warning for Ash Waterways

Poisonous Plant Warning for Ash Waterways

As autumn turns to winter and vegetation begins to die back, residents walking along the Basingstoke Canal, local lakes, rivers and streams should remain aware of hemlock water-dropwort (Oenanthe crocata), one of the most poisonous native plants found in the UK.

While the plant’s distinctive white flower heads disappear by late summer, it can still often be identified in November by its thick hollow stems, divided bright green leaves and its preference for wet ground along waterways, ditches and pond edges. Dead or decaying stems may also remain visible through the winter months.

Hemlock water-dropwort is frequently confused with harmless members of the carrot and parsley family. However, all parts of the plant are highly toxic, especially the roots, which contain potent poisons capable of causing serious illness or death if eaten. Dogs can also be at risk if they dig up or chew exposed roots.

Residents are advised not to touch or pick any plant they suspect may be hemlock water-dropwort, and to keep children and pets away. If you think you have found the plant on public land, report it to the relevant landowner or authority, such as Surrey County Council, the Basingstoke Canal Authority, or the local council responsible for the site.

When enjoying Ash’s waterways this autumn, admire wild plants from a distance and leave identification to the experts if there is any doubt.