An uncommon hedgerow and woodland tree of central and eastern England, Purging buckthorn displays yellow-green flowers in spring, and poisonous, black berries in autumn.

The fine, downcurved bill of the treecreeper makes this tit-sized bird unmistakeable. Look out for it in woodlands and parks, literally 'creeping' around tree trunks.

The Common walnut tree produces a large, brown nut that is familiar to so many of us. It is an introduced species in the UK, and can be seen in towns, gardens and parks.

Barnacles are so common on our rocky shores that you've probably never really noticed them. They're the little grey bumps covering the rocks that hurt your feet when you're…

An uncommon tree of wet woodlands, riverbanks and heathlands, Alder buckthorn displays pale green flowers in spring, and red berries that turn purple in autumn.

A common tree, ash is familiar to many of us for its autumnal bunches of winged seeds, called 'keys'. It can be found in woodlands and prefers damp and fertile soils.

A scarce tree of England and Wales, the Large-leaved lime is the rarest of our native limes. It is tall and broad, and can be found in forests and parks, where it is frequently planted.