Side by side
What tells them apart
They grow side by side in the same shade and the lower leaves are confused. Nipplewort has leaves with a large round terminal lobe and yellow flowers; herb Robert has leaves divided into five segments, red stems and pink flowers, and smells bad when crushed. Neither is dangerous.
Harmless confusion
How to tell it
The lower leaves have a large rounded terminal lobe and two or three pairs of small lobes behind, on a winged stalk. Small heads, a centimetre across, with only eight to fifteen ray florets, which makes them look like stars rather than daisies. It makes no flying seed plume. White latex.
How to tell it
Red, brittle, hairy stems that break at the slightest touch. Leaves divided into five segments, each cut again, on a long stalk. Bright pink five-petalled flowers with paler stripes. A strong unpleasant smell when rubbed, which many people recognise without knowing from where.