Our Veteran Oak
This veteran tree is estimated to be around 450 years old. This makes it a survivor from the reign of Elizabeth I. This was a time when oak timber was so sought after that laws had to be passed to protect oak trees.
Our tree is 26.5m high and has a girth of 6.75m. It is however clearly a managed tree. At some point in its life this tree was pollarded.
Our tree used to be part of a boundary hedge around the field. Without agricultural disturbance it became surrounded by other smaller trees – many of which are likely to be its descendants. This shrub and tree growth meant that progressively less light could reach the main trunk and lower part of the big polls. To ensure that new growth sprouts will form it is necessary to cut down some of the shading vegetation – tree professionals refer to this practice as ‘halo release’.
In 2023 we carried out a first ‘halo release’ – you can see before and after views in the gallery below. By doing this we can help the oak to retain its vigour as it gets older.
You too can help by not walking up to the base: instead admire this magnificent tree from the “viewpoint” on the main path. That way we minimise any compaction which can restrict the tree roots from valuable air, water and nutrients. To find out more about best practices in looking after old trees Kew Gardens describe their approach here.
So stop a while and consider the tree ……. Think about all the other people and animals that have come into contact with this particular veteran in its life; and think of the future visitors.
Pollarding is a traditional method of cropping timber without felling the tree. The tree is cut at over 2m height above ground to ensure that no grazing animals can reach the new growth. All the top branches are removed leaving only a tall stump. The tree regrows its crown, but instead of one main stem several shoots sprout at the same time so the crown post-pollarding has several similar size trunk branches or ‘polls’. Traditional pollarding was carried out on a cycle so each tree was pollarded repeatedly perhaps every 20-30 years depending on the species and the intended use for the timber. The result is that the main trunk below the pollard point is oversized in relation to the size of the crown.
A feature of this veteran tree is the obvious damage caused by fire. Thankfully the vandals who lit fires within the trunk some years ago did not cause the death of the tree. To lose such a magnificent tree would lessen our enjoyment of this part of the site, and would be a significant loss in biodiversity – the oak is the top UK tree species in terms of the number of other species that it supports, and older trees support more species than younger trees.
Oak trees as they grow old have a clever trick to keep in good health – they can deliberately shed branches to reduce the size of their crown. Our tree has certainly done this in the past as the two large fallen polls show. How does this work? Every year a tree has to grow a new layer of water carrying cells around the trunk and branches (just below the bark). This takes energy which comes from the leaves in sunlight. The energy required is greater the bigger the tree gets, by dropping a poll and all its branches the tree needs less energy. When a poll or branch is shed new growth sprouts appear just below the break point.