An easily overlooked orchid, the Common twayblade is yellow-green and less showy than other UK orchids. Look for it in woodlands and grasslands on chalky soils, in particular.

Greater celandine is a very common plant that spreads easily in the garden, on waste ground and in hedgerows. It is considered a weed, but the small, yellow flowers provide nectar for insects.

Ivy-leaved toadflax is an introduced species in the UK that has become widely naturalised. Look for creeping along old walls and pavements, and shingle beaches. Its flowers resemble those of…

Tall melilot was introduced into the UK as a fodder crop, but has now become naturalised. It displays golden, pea-like flowers on tall spikes, which are followed by black, hairy seed pods.

With a population of 75 million, the field vole is one of the UK's most common mammals. Hidden among the vegetation of grassland, heathland and moorland, it is not as easily spotted as the…