Due to the devastating effects of Dutch elm disease in the 20th century, wych elm is rarely found as a large tree, but is more common as a shrub along hedgerows and streams, and in upland areas.…

The peppered moth is renowned for its markings that have evolved to camouflage it against lichen in the countryside and soot in the city. It can be seen in gardens, woods and parks, and along…

The Sitka spruce was introduced into the UK from North America in the 19th century. It has been widely planted as a forestry tree; look for classic needle-like leaves and pale brown, domed cones…

Introduced from Japan in the 19th century, Japanese knotweed is now an invasive non-native plant of many riverbanks, waste grounds and roadside verges, where it prevents native species from…

These non-native limpets arrived from America in the 19th century and are now widespread in the UK. They form stacks and have a specially adapted shell which, when flipped upside down, looks like…