The grey squirrel was introduced into the UK in the 1800s. It provides an easy encounter with wildlife for many people, but can be damaging to woodlands and has contributed to the decline of the…

Look for Water avens in damp habitats, such as riversides, wet woodlands and wet meadows. It has nodding, purple-and-orange flowers that hang on delicate, purple stems.

Sand sedge is an important feature of our coastal sand dunes, helping to stabilise the dunes, which allows them to grow up and become colonised by other species.

Creeping jenny is a low-growing plant of wet grasslands, riverbanks, ponds and wet woods. It has cup-like, yellow flowers and is a popular choice for garden ponds.

Although introduced by humans, the fallow deer has been here so long that it is considered naturalised. Look out for groups of white-spotted deer in woodland glades.

A fierce predator of small fish and flying insects, the brown trout is widespread in our freshwater rivers. It is has a golden body, flanked with pale-ringed, dark spots.

Buddleia is a familiar shrub, well-known for its attractiveness to butterflies. It is actually an introduced species, however, that has become naturalised on waste ground, railway cuttings and in…

A scrambling plant, Bush vetch has lilac-blue flowers. It is a member of the pea family and can be seen along woodland edges and roadside verges, and on scrubland and grassland.

The candlesnuff fungus is very common. It has an erect, stick-like or forked fruiting body with a black base and white, powdery tip. It grows on dead and rotting wood.

Dyer's greenweed is a classic plant of hay meadows, heaths and open woodlands. It has upright stems with loose clusters of bright yellow, pea-like flowers in summer.

Large scale drainage in the UK has seen a massive reduction in the range of this sensitive aquatic plant which now only occurs in around 50 sites in England.

The green-veined white is a common butterfly of hedgerows, woodlands, gardens and parks. It is similar to other white butterflies, but has prominent green stripes on the undersides of its wings.…