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…

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…

The Common fragrant-orchid lives up to its name: it produces a sweet, orangey smell that is very strong in the evening. Look for its densely packed, pink flower spikes on chalk grasslands in…

The Holm oak is an introduced species that has been widely planted near the coast and in parkland. It is self-seeding in the south of the UK. Its young leaves are spiny like Holly leaves, and it…

So-named because its gnarled trunk can split as it grows, the Crack willow can be seen along riverbanks, around lakes and in wet woodlands. Like other willows, it produces catkins in spring.