The tightly packed, thistle-like purple flower heads of common knapweed bloom on all kinds of grasslands. Also regularly called black knapweed, this plant attracts clouds of butterflies.

The ragged-edged, purple flower heads of Greater knapweed bloom on sunny chalk grasslands and clifftops, and along woodland rides. They attract clouds of butterflies.

The Black darter is a black, narrow-bodied dragonfly that can be seen throughout summer and autumn. It is hovers around damp moors, heaths and bogs, darting out to surprise its prey.

A climbing plant of hedgerows and woodlands, Black bryony produces greenish flowers in summer and red, shiny berries in autumn. It is a poisonous plant.

The pungent, rotten smell of Black Horehound makes this medium-sized plant of waste ground and roadside verges stand out from the crowd.

The black hairstreak is a rare butterfly that is restricted to woodlands and hedgerows containing blackthorn - the foodplant of the caterpillar. It is both elusive and hard to tell apart from…

The black poplar is a large tree of floodplains, flooded gravel pits and ditches, particularly in England. Despite being an important part of our culture for centuries, it has declined massively…