Familiar as the bristly plant that easily hooks on to our clothing as we walk through the countryside or do the gardening, cleavers uses its hooks to help it climb and to disperse its seeds.

Living up to its name, the bullhead has a characteristically large, flattened head and a tapering body. Look out for it in fast-flowing, stony rivers and streams.

Look out for the white, umbrella-like flower heads of lesser water-parsnip along the shallow margins of ditches, ponds, lakes and rivers. When crushed, it does, indeed, smell like parsnip!

This hefty diving bird is a winter visitor to the UK, where it can be seen around the coast or occasionally on large inland lakes.

Mae'r rhywogaeth yma o forwellt yn fath o blanhigyn blodeuol sy'n byw o dan y môr, gan ddarparu cynefin pwysig i lawer o rywogaethau prin a rhyfeddol.