So-named for the silvery-white appearance of its leaves, the White willow can be seen along riverbanks, around lakes and in wet woodlands. Like other willows, it produces catkins in spring.

With black-and-yellow markings, the hornet mimic hoverfly looks like its namesake, but is harmless to us. This mimicry helps to protect it from predators while it searches for nectar.

The common spangle gall wasp produces a small, disc-shaped growth, or 'gall', on the undersides of oak leaves. Inside the gall, the larvae of the wasp feed on the host tissues, but cause…

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…

Also known as 'Scorpion-grass' because of the curved 'tail' at the end of its stems, Water forget-me-not is a distinctive plant of damp habitats. Over summer, it produces…

The knopper gall wasp produces knobbly red, turning to brown, growths, or 'galls', on the acorns of Pedunculate Oak. Inside the gall, the larvae of the wasp feed on the host tissues, but…

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…