As its name suggests, Himalayan balsam is from the Himalayas and was introduced here in 1839. It now an invasive weed of riverbanks and ditches, where it prevents native species from growing.

The tiny, brown-and-white sand martin is a common summer visitor to the UK, nesting in colonies on rivers, lakes and flooded gravel pits. It returns to Africa in winter.

As its name suggests, giant hogweed it a large umbellifer with distinctively ridged, hollow stems. An introduced species, it is an invasive weed of riverbanks, where it prevents native species…

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.

It's easy to see where this small starfish got its name, it really does look like a little star-shaped cushion. Keep an eye out under rocks next time you're rockpooling for this little…

The brimstone moth is a yellow, night-flying moth with distinctive brown-and-white spots on its angular forewings. It frequently visits gardens, but also likes woods, scrub and grasslands.

In May, our hedgerows burst into life as common hawthorn erupts with creamy-white blossom, colouring the landscape and giving this thorny shrub its other name of 'May-tree'.

Traditionally a coastal species, Lesser sea-spurrey has spread inland, taking advantage of the winter-salting of our roads. Its pink-and-white flowers bloom in summer.

In May, our hedgerows and woodland edges burst into life as Midland hawthorn erupts with masses of pinky-white blossom. During the autumn, red fruits known as 'haws' appear.

The pied wagtail is a familiar bird across town and countryside. Its black-and-white markings and long, wagging tail make it easy to identify as it hops across the road or lawn.