In the Spotlight - The Mighty Oak Tree

The English Oak Tree

The English oak is probably Britain's best known and most well-loved of all our native trees, but how much do you know about it? If the answer is "not much", then have a brief read to find out more about one of our finest trees.


Its common name is of course the English oak, or pedunculate oak but its scientific name is Quercus robur (meaning strength). The oak tree belongs to the Fagaceae family, which is a family of flowering plants that includes beeches as well as oaks and comprises eight genera with around 927 species.

How long can an oak live?

Oak trees can often live for up to 1000 years. One of the UK's oldest, and biggest oak trees is the Major Oak which is also known as the Robin Hood Oak. It stands at the heart of 450-acre Sherwood Forest Country Park and Sherwood Forest Visitor Centre which is run by Nottinghamshire County Council. Its stats are impressive; It weighs about 23 tons, has a girth of ten metres (33ft) and a spread of 28 metres (92ft). No one is quite sure how old the Major Oak is, as it would have to be cut down to explore its rings to get a truly accurate date. It's reputedly some 800 to 1000 years old and some speculate that it was only a mere acorn when Robin Hood was galavanting through Sherwood Forest!

Annual Oak Tree Life Cycle

Here's a brief, but beautiful video of a year in the life of a typical oak tree, courtesy of the Woodland Trust. The video takes us on a journey as we ride the seasons and watch the tree soak up the warmth of the summer sun before retreating back to its dormant state in winter.

When to expect the first acorn

If you've just planted a small oak in your garden, you'll have a bit of a wait until you see your first acorn. These aren't produced until the tree is at least 40 years old and you can expect it to be producing a mass of acorns at around 80 to 120 years; just in time for the grandkids to enjoy them :)

Oak Tree Mythology and Popularity

The oak is revered and respected across much of Europe. As they live so long, they're often the tallest tree around, making them particularly susceptible to lightning strikes. As such, they were seen as sacred to well-known Gods of thunder and lightning including the Greek god Zeus, the Roman God Jupiter and the Celtic God Dagda.

Even today, Druids will perform rituals where there is an abundance of oak trees and they also favour the mistletoe which can often be seen growing on them in the colder months. Royalty has many connections to the ancient oak as well. It's said that King Charles II hid from his pursuers in an oak tree at Boscobel House, and kings of old frequently adorned themselves with crowns of oak leaves. Roman Emperors were known to be presented with crowns of oak leaves during victory parades after their triumphant battles, probably because the oak tree is seen as a symbol of strength and survival.

Back in the 1600s, marriage ceremonies would be performed under an oak tree and the Yule Log we're all familiar with at Christmas time is traditionally cut from an oak. In case you hadn't noticed, you'll also see it on later 1980s pound coins. Even the Woodland Trust uses the leaves as part of its logo.

Oak Tree wildlife

Oak trees generally support more life forms than any other native trees. The leaves, branches, and fruit (the acorn) play host to literally hundreds of species of insect and are a crucial source of food for our British bird population.

Whilst an oak tree can produce many acorns, very few of them actually make the transition from seed to plant. The acorn is a rich source of food to many wildlife species including badgers and deer, who make the most of the bumper autumnal seed-fall from the tree.

They're also a rich source of food for jays, mice and of course, squirrels. Most acorns are unable to root quick enough and instead become a tasty treat for wildlife. Fortunately, some manage to make it, and you'll see the tiny new shoots of the lucky survivors appearing the following spring.

The flowers and leaf buds are tasty treats for the purple hairstreak butterfly caterpillar. As there are often plenty of nooks and crannies in the mighty oak, its also an ideal nesting spot for the pied flycatcher or marsh tit. Some bat species occasionally roost in old woodpecker holes or under loose bark, whilst being able to take advantage of the rich supply of insects that frequent the canopy of the tree.

And that's not all, the leaves are extremely rich in nutrients and as they fall from the tree in autumn and begin to decay, they provide a vital source of food for many invertebrates, such as the stag beetle and also for fungi like the oakbug milkcap.

How do we make use of oak trees?

The oak tree produces an extremely hardy and durable wood that has been a favourite of carpenters and builders for thousands of years. It's certainly not cheap to buy as it takes a good 150 years before the tree can be felled to use in construction. It was pretty much exclusively used in shipbuilding during the 1800s and was the wood of choice for the strong beams used in house building. You'll also still see it in use today in the form of attractive wood flooring and traditional wine barrels. The tannin found in the bark was also used to tan leather since at least the time of the Romans. 

Medicinal and food use

It was a commonly held belief that the leaves, bark and acorns had beneficial medicinal properties. These were frequently used to help alleviate diarrhoea, inflammation and deal with kidney stones. It may surprise you to know that the acorns were also collected so that they could be processed into flour for breadmaking, although this practice has died out due to high yielding wheat crops taking the acorn's place. Whilst I'd love to try some oak bread, I'm happy that our wildlife now has their stash of acorns all to themselves once again.

Poison alert

As most horse riders will know, the tannic acid in the leaves is poisonous if the horse is allowed to eat too much of it as it can seriously damage their kidneys. Whilst the same applies to cattle, pigs are able to eat them in moderation.

A final note and cause for concern

Although you'll most likely see many healthy oak trees if you go for a stroll in the countryside, their numbers are being threatened by a number of pests and pathogens. The oak processionary moth is a non-native pest that has been spotted in the south of England. It damages the foliage of the tree, making it more susceptible to other diseases. The moth's hairs are also toxic to humans, causing skin and respiratory irritation problems.

There are also diseases that are starting to affect oak tree numbers including 'acute oak decline' (AOD) and 'chronic oak decline' (COD). First noted in the 1920s, these diseases cause canopy thinning, branch dieback and black weeping patches on the stems of the tree. Fortunately, these conditions are primarily only found in the south of England.

So there you have it - If you've made it this far, you probably know more about the Mighty English Oak than most of your friends and family.