Not to be confused semantically with : another non-native plant with the same common name 'Black-eyed-Susan' (Thunbergia alata) which is a climber with ace-of-spades shaped leaves like those of Bindweeds and yellow flowers with five petals and a deep well in the middle that looks black because it is so deeply set. Nor to be confused with Blue-eyed-Grass (Sisyrinchium bermudiana) which is not a grass either.

Easily mistaken (especially in regard to the way that a certain once-popular but out-of-print botanical book draws Blanketflower) for : Blanketflower (Gaillardia × grandiflora) but that has ray florets that are deeply pinked into three large teeth at the periphery much like those of Sweet William (Dianthus barbatus) and the leaves are coarsely and dentately toothed on the sides (whereas the leaves of Black-eyed-Susan are entire, lacking teeth.

Some similarities to the related : Hairy Rudbeckia [aka Bristly Coneflower] (Rudbeckia hirta) but that has an all-yellow corolla but a similar beetroot-coloured domed central 'cone'.

Black-eyed-Susan is a garden plant that can escape into the wild, usually onto rough ground and waste places. The specimens here are yet to escape...

The stems appear to be very variable in cross-section, the above photos show round, multi-faceted, ribbed and square stems. All have long thin white hairs emerging from dark glands. Lanceolate leaves hairy too and lacking teeth.