Common couch is a tall, tuft-forming grass of roadside verges, waste ground and arable land. It is very tough and can shade out more delicate plants. Look for flat, blade-like leaves and thin…

The oak marble gall wasp produces brown, marble-shaped growths, or 'galls', on oak twigs. Inside the gall, the larvae of the wasp feed on the host tissues, but cause little damage.

This striking black-and-white moth flies during the day in open woodlands, moorlands, and bogs. It's most common on Scottish moors.

Look for Water avens in damp habitats, such as riversides, wet woodlands and wet meadows. It has nodding, purple-and-orange flowers that hang on delicate, purple stems.

Look for wood avens along hedgerows and in woodlands. Its yellow flowers appear in spring and provide nectar for insects; later, they turn to red, hooked seedheads that can easily stick to a…