Wild cherry
Wild cherries or geans are northern Eurasian trees that can grow to 30 metres tall and live more than 60 years. They are usually found on the edges of mixed broadleaf woodlands and hedgerows, where they require plenty of light to thrive and ripen their fruit. Cherry trees have red-brown, tiger-striped bark. The stripes comprise lenticels, which are pores facilitating the direct exchange of gases from inside the tree to the outside air.
The Latin 'avium' probably refers to birds that eat the fruit and disperse the seed. Wild cherries are one of our most beautiful native trees but also very important for wildlife, the masses of white cup-shaped flowers in spring provide an early source of pollen and nectar for many pollinators. The fruits, which ripen in July, make up the diet of several birds and mammals. Cherry stones (pits) either pass through an animal's digestive system or are dropped when flesh is stripped from the fruit.
It was once thought cherries first arrived in Britain from Persia with the Romans, in the first century CE, with Roman roads marked by cherry trees along their length, where stones were spat out by passing soldiers. However, cherry stones have been found in Bronze Age settlements across Europe from at least 2000 BCE.
The fruit of wild cherry is the only non-poisonous part of the tree. Cherry stones contain amygdalin, a cyanogenic glycoside which, when chewed, mixes with various enzymes and releases cyanide. Cherry twigs and leaves contain prunasin, a cyanogenic glycoside related to amygdalin. Annually, there are reported occurrences of cyanide poisoning in horses following the ingestion of cherry leaves.
Prunus avium is thought to be one of the ancestors of cultivated cherries, and is commonly used as the root stock for garden varieties found across Europe and western Asia. Dozens of cherry cultivars were grown in the seventeenth-century Oxford Physic Garden.
At the base of the blade of a cherry leaf there are two extrafloral nectaries, which are thought to protect the plant's leaves from damage by herbivorous insects. The nectaries attract ants by producing small quantities of sugar-rich nectar, which appears to encourage additional patrolling by ants. If the ants encounter any caterpillars they aggressively defend the leaf, even carrying the offending animal back to their nests.
Cherry wood is particularly attractive and is highly valued for furniture building, veneers, musical instruments, hop poles and even tobacco pipes.
Further reading
Hemery G and Simblet S 2014. The new Sylva. A discourse of forest & orchard trees for the twenty-first century. Bloomsbury.
Tilman D 1978. Cherries, ants and tent caterpillars: timing of nectar production in relation to susceptibility of caterpillars to ant predation. Ecology 59: 686-692.
Vanessa Newman