Freshwater pearl mussels spend their adult lives anchored to the river bed, filtering water through their gills and improving the quality of the water for other species.

Great mullein is an impressive, tall plant of waste ground, roadside verges and gardens. Its candle-like flower spikes rise from rosettes of furry, silver-green leaves.

Lilac is an introduced species in the UK that can sometimes be found in hedgerows and along woodland edges. Flower spikes appear in spring, beautifully scented and packed with small, lilac-pink…

The disc-shaped leaves and straw-coloured flower spikes of Navelwort help to identify this plant. As does its habitat - look for it growing from crevices in rocks, walls and stony areas.

Soft brome is a tall, annual grass of roadside verges, waste ground and meadows, and is a 'weed' of arable land. It has long, grey-green leaves and loosely clustered flower spikes.

As its name suggests, pendulous sedge has drooping form with long, nodding flower spikes that give it an attractive and soft look. It can be found in wet woodlands and along riversides.

Tall melilot was introduced into the UK as a fodder crop, but has now become naturalised. It displays golden, pea-like flowers on tall spikes, which are followed by black, hairy seed pods.

The aromatic fragrance of Large thyme can punctuate a summer walk over a chalk grassland. It is an evergreen that grows low to the ground, with erect spikes of tiny, lilac flowers appearing over…