This small  member of the pea family, is easily overlooked, but  it is there in amongst the grasses in the Reserve.  It is similar to the Black Medic, and Hop Trefoil.

It is thought that this plant may be the shamrock  used by St Patrick, as it is worn by Irish people on the saints  day .

Each yellow flower produces a brown seed pod, containing a seed.

It is quite common in UK and is often to be found on road-side verges.