Country diary: delving deeper into crab apples' DNA

Bishop Auckland, County Durham: Most candidates are descended from discarded cores of domesticated orchard apples, complex hybrids whose ancestors came from the Tian Shan mountains of Kazakhstan

Genuine native crab apples (Malus sylvestris) are notoriously difficult to identify with certainty. In a 1979 survey, only 1% of 3,000 hedgerow crab apple trees in County Durham ticked all the boxes as being the authentic native species. Most candidates are descended from discarded cores of domesticated orchard apples, complex hybrids whose ancestors came from the Tian Shan mountains of Kazakhstan.

I’ve long suspected that one venerable example, in a fragment of ancient oak wood that lies within the boundary of the Prince Bishops’ deer park, might be the genuine article. Bark, leaves, flowers and fruit match descriptions in field guides but I’ve harboured lingering doubts that perhaps it, too, might be descended from a culinary apple core, cast aside during a picnic in the park, long ago.