Oak : Oak Crops and Trees

Oak

The oak is perhaps one of the most widely recognized trees in the UK. There are two members of the species native to this country: the Common, or Pedunculate Oak (Quercus robur) and the Sessile Oak (Quercus petraea).

The 100 year-old crop

Both trees are relatively slow growing, taking approximately 80 to 100 years to become ‘mature’ trees in commercial forestry terms. Forestry is perhaps the only crop that has a longer rotation than the humans that plant it, and it can be difficult for those outside the industry to grasp the implications of planting crops to be harvested by future generations and harvesting crops planted by preceding generations.

A commonly accepted approach to tree planting is to plant the trees in rows at set spacings within the rows. Oak can be notoriously difficult to establish, sometimes losing 75% or more of all trees planted. Gradually as the plants turn into saplings and young trees, the poorer specimens are removed to allow more room for the growth of the stronger plants. This technique, of removing poorer plants to make room for the better ones, continues on a regular basis throughout the life of the crop and is known as thinning.

The thinnings help provide a return to the forester for their investment in planting and maintenance work before the final crop is taken. In the past it was usual for a parcel of woodland to be clear felled before beginning the whole rotation anew. Today however most forestry managers try to maintain a more diverse range of trees on the same ground to reduce the visual and environmental impacts of clear felling.

Uses of oak

Oak trees may be converted at or near the site into firewood or split to form fence posts and rails. Better quality oak will be transported to a sawmill where the trunks are sawn lengthways to be used for a variety of purposes, such as timber beams for buildings or planks for joinery work.

Planks will be stacked on stringers, small cross pieces of wood, to allow the air to circulate and season the timber. After a number of years the planks will then be subjected to a final seasoning in a kiln to further reduce the moisture content and make the wood suitable for joinery.

English or Welsh Oak is extremely tough and durable and has an attractive colour and grain that has made it highly desirable for furniture making and wood panelling for many hundreds of years. When the tree has been sawn into planks in a particular way, the finished furniture exhibits silvery gold flecks in the grain, which are the medullary rays or veins that run horizontally outwards through the wood of the living tree.

Oak around the world

Members of the oak species are found almost everywhere in the world. Their properties and appearance varies from region to region. In North America there are many varieties of Red Oak (as opposed to the White Oak of Europe) and in the Far East there is Japanese Oak. Perhaps one of the most startlingly different oaks is Quercus suber, better known as the Cork tree, from which cork is harvested for making bottle corks.

Oak in British history

It is perhaps not surprising that such an important tree should be so interwoven into the fabric of British culture and history. The oak tree had a special significance for pre-Christian religions in Britain and the Pagan Green Man is frequently depicted using oak leaves. Many pubs are called the Royal Oak in commemoration of the oak tree in which King Charles II hid from the Roundheads.

Oak was also of great strategic importance to Britain when it was the primary material used for building the Royal Navy’s ships. It is no co-incidence that ‘Hearts of Oak’ is the official march of the Royal Navy. Concerns over having enough oak for shipbuilding led, for example, to the development of the Forest of Dean in Gloucestershire. The depredation of Britain’s oak woodlands during the First World War (for the trenches) served once again as a reminder of their importance and led to the establishment of the Forestry Commission in 1919 to replenish lost stocks.