This glossy wading bird is a scarce visitor to the UK, though records have become more common in recent decades.

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.

Sphagnum mosses carpet the ground with colour on our marshes, heaths and moors. They play a vital role in the creation of peat bogs: by storing water in their spongy forms, they prevent the decay…

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…

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.