Groundsel
Senecio vulgaris
Family · Asteraceae · Poisonous
Read this before the sheet
This plant, or one that resembles it, is dangerous. Identifying is not authorising: no app has the authority to tell you that you may eat or touch a plant.
Emergency

The garden and pot weed that flowers all year and passes for harmless because it is everywhere. It is not: it contains alkaloids that accumulate in the liver and are not cleared.
Town and roadside · Fields and pasture · Roadsides and waste ground
Also known ascommon groundsel, old-man-in-the-spring
How to tell it
Small cylindrical yellow heads with almost no visible petals, ringed by green bracts with black tips, which is the most reliable sign. Soft, deeply cut leaves clasping the stem. It goes to a white seed ball within days.
What it is confused with
Sow thistle
Sonchus oleraceus
Both verge plants with cut leaves, and one is eaten and the other is not. Sowthistle has open yellow flowers like small dandelions and bleeds white latex; groundsel has closed cylindrical heads and no latex.
What it is for
None
The pyrrolizidine alkaloids cause cumulative liver damage, and recorded poisonings come mostly from home infusions and contaminated fodder. Do not feed it to rabbits or birds, contrary to long practice.
Where it occurs
Each square is an area with recorded observations of this plant. The lighter background is the set of areas where any of the entries has been observed, and serves as a reference. Note what this is not: it is not where the plant lives, it is where people record it, so trails and towns always look fuller than the mountains. Data from GBIF.
Sources
Community
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