Plymouth pear  (Pyrus cordata)

The Plymouth pear is smaller than its more common relative and grows as a hedgerow tree. It may be distinguished from the common wild pear by purplish twigs (instead of grey-brown) and, in the words of its discoverer T. R. Archer Briggs, 'plentifully furnished with spines'.

The plant is restricted to Western Europe with populations in France, particularly Brittany, and the north-western regions of Spain and Portugal. In Britain it is found on only two wild sites together with some transplanted trees within the city of Plymouth in Devon and near Truro in Cornwall.

Although the UK population survives in hedgerows, it is thought originally to have been a component of mixed deciduous woodland and, in Brittany, the plant still occurs in this habitat.

In the shaded conditions in which it grows, this plant reproduces by suckering. Only in places where it receives enough light such as hedgerows or in woodland glades does it flower and bear fruit.

Plymouth pear flowers later than wild pears, usually around late April or May, with a spectacular show of pink-tinged blossoms and purple stamens. The small, inedible fruit are usually about 15 mm in diameter.

The plant seems unable to cope with environmental change and, in the UK, the Plymouth pear has suffered as a result of unsympathetic management and removal of hedgerows. Industrial developments in its namesake city have contributed to its decline and it is also at risk from disease and cross-fertilisation with domestic and other wild pears.

The pear often fails to produce viable seed and while it suckers readily, it is not always possible to ascertain a true identification from suckered trees.

Because of the threat to the survival of the Plymouth pear it has been included in English Nature's Species Recovery Programme. A three-year contract was established with the Royal Botanic Gardens at Kew to produce a conservation strategy, safeguard the existing population and re-establish the pear within its historic range.

One of the first tasks was to determine the genetic profile of the plant. This would enable a breeding and propagation programme to begin using controlled hybridisation. The young trees could then be transplanted within a suitable, protected site and form a 'nursery' stock for re-introductions elsewhere at a later date.

Trees growing wild in Brittany provided a template for soil type and environmental suitability as well as genetic validation and the National Trust's Regional Headquarters at Lanhydrock was chosen as the first re-introduction site.

Since the first genetic profiling, carried out by Reading University, more individual trees have been discovered growing near Truro in Cornwall. It is possible that more Plymouth pears may be found.

See also Royal Botanic Gardens, Kew:
http://www.rbgkew.org.uk