Great Lettuce - Lactuca virosa

Tall plant to 2 metres, with stems often prickly below and often tinged maroon. Upper leaves horizontal, finely prickly beneath the mid-rib which usually purple/maroon. Flower-heads in a pyramidal panicle. Achenes (i.e. ripe 'seeds') maroon to blackish.

Lactuca serriola (Prickly Lettuce)

Leaves very variable, but more often lobed, and usually maroon tinged; stem and prickly midribs also tinged maroon.  Ripe achenes ('seeds') maroon to blackish - this is the most reliable feature

A clear image (or several) showing leaves and stem is usually sufficient. Ideally a close-up of the seeds if available.

Disturbed ground, roadside verges, waste places & banks of streams.

July to September.

Annual or biennial.

Widespread in central and south-eastern England, scarcer elsewhere in Britain.

Infrequent but perhaps increasing in Leicestershire and Rutland. In the 1979 Flora survey of Leicestershire it was found in 14 of the 617 tetrads.