Plant 146

Quercus robur L. (Fagaceae)


Pedunculate oak

The oak must be one of the most loved and favoured native trees in Great Britain and one of the few trees nearly every one can identify. There are two native British oaks, the pedunculate oak and sessile oak (Quercus petraea). These trees have been involved with the development and the history of our country over thousands of years and are extremely important to the ecology of British forests and landscapes.

Oaks grow well in woodland environments, which mean they produce very good quality, strong, straight and long-lasting timber. This makes it ideal for timber frame buildings and ship construction, and is why many of our old buildings are still able to stand today; the British Navy even use the song, 'Heart of Oak' as its official marching song. However, oak was such a valuable and important commodity it was reserved for the most important buildings, therefore, historically, contrary to popular belief, most buildings in rural environments were constructed using lower value timbers.

Historically, many of our oak woodlands have been managed on one-hundred-year cycles, that is, they would be harvested, replanted and left to grow for a century before being cut down again. One advantage of oaks is that they grow in open parkland settings and, like many of the oaks at Harcourt Arboretum, produce iconic, impressive, broad-branched, grand trees.

Some of the oldest trees in Great Britain are oaks and they can live for well over one thousand years, such trees tend to be very squat with impressively wide girths. They are often covered in bracket fungi and full of cavities, although this does not usually stop them from plodding along into a very old age. Age and heterogeneity are two of the reasons why oaks are so important in British ecosystems; one oak is able to support more than 1,000 different species, from bats all the way through to lichens and algae.

Both jays and squirrels commonly eat the characteristic acorns that oaks produce, are the main ways the seeds are dispersed, and prepared for germination. Not just wild animals like the acorns. In mast years, when large numbers of acorns are produced, they can be important food for domesticated pigs, and a source of flour for making bread and wine. With many of our native trees under threat, oaks are one of our most tolerant and important trees that are likely to be round for years.

Further reading

Hemery G and Simblet S 2014. The New Sylva. A discourse of forest & orchard trees for the twenty-first century. Bloomsbury.

Rackham O 1995. Trees and woodlands in the British landscape. The complete history of Britain's trees, woods and hedgerows. Weidenfeld & Nicolson.

Guy Horwood