Country diary: in the fight to survive, red campion is a surprise battleground

Brancepeth, County Durham: These small flowers are prone to an extraordinary parasite

A wild tangle of brambles covers this section of embankment beside a former railway line. A wren scolds from the undergrowth. Drone flies hover in the sun flecks filtered through overhanging branches of wild cherry. Butterflies chase through dappled shade. But what has stopped us in our tracks today are drifts of red campions.

It's a glorious display, although something strange is happening to many of the flowers. Where there should be stamens, shedding white pollen, there is brown powder resembling cocoa, staining the petals. They have a sexually transmitted fungal disease, a type of red campion anther-smut" called Microbotryum silenes-dioicae.