Alasdair Fagan – Conservation Graduate Trainee
Alex (my fellow Conservation Graduate Trainee) and I have been tasked with the discovery, measurement and recording of each of the veteran trees on the Hawnby estate on the western side of the National Park. This is an area noted for its high proportion of tree cover which is a characteristic of the landscape in this part of the North York Moors.
Ancient and veteran trees are of high importance biologically as they support a diversity of different plants, birds, fungi, bats and insects. The Natural England FEP Guidance – Ancient Trees defines veteran and/or ancient trees as ‘Trees that are or look old relative to others of the same species’. Characteristics include:
- Very large girth for the species
- Hollow or hollowing trunk
- A large quantity of dead wood in the canopy
The veteranisation of a mature tree is the first indication of the tree’s truly old age and as a part of this inevitable ageing, provides visual signs that the tree has begun to approach the end of its life (hundreds of years in the case of some trees) and in the meantime provides valuable habitats through processes like the decaying of wood.
Different species of trees have differing lifespans and so some tree species will reach maturity and veteran status much quicker (Silver birch for example) than those with longer life expectancy (such as Oak). A difference in the length of time it takes trees to veteranise is inherently valuable to the biodiversity of the area’s ecology, providing habitats for those organisms that depend on a continuous cycle and creation of veteran characteristics to survive.
Data recorded from the Ancient Tree Hunt suggests that there are over 102,200 Veteran and Ancient trees in Britain, giving it the highest proportion of Ancient tree cover in the whole of Europe. But there are still parts of the country that have yet to be fully surveyed for these important trees.
This particular survey that Alex and I are carrying out on Hawnby estate involves identifying the species of each veteran tree and recording the tree’s girth, condition, any biological interests associated with the tree, and any threats currently posed to the tree that we might be able to address in order to ensure that it is able to endure for as long as possible.
We’ve used aerial photographs, and Ordnance Survey modern and historical maps (including from over 150 years ago) to establish areas where we suspect there may still be important, notable and veteran trees that aren’t yet part of the Ancient/Veteran tree current record.
We use GPS to record the location of each of the trees we record. Being able to see where veteran trees are across the North York Moors and being able to compare associated data allows us to build up a picture of this asset and to target efforts to keep the trees going as long as possible and at the same time to plant and manage new generations of trees nearby.
The search for veteran trees has so far proved eventful with a valuable opportunity to experience the beauty of the North York Moors National Park during autumn. We’re now up against the seasons as autumn has turned into winter and so it inevitably becomes harder to identify tree species without leaves.
An Unexpected Encounter
We also had a number of encounters with wildlife and the seasonal timing of the survey ensured that we got the chance to see many weird and wonderful species of Fungi.
Something that Mark the Woodland Officer here at the National Park told me when I first began: ‘whenever you look at a veteran tree, always make sure you walk all the way around it first’. Good advice indeed as it is often very easy to assume a tree is in good health when judging it on its appearance from one side, but on further inspection the other side may reveal that the tree is entirely hollow and well into its decline phase. Because of this advice, during the survey Alex and I decided to investigate what appeared to be a dead/relic branch that was still partly attached to the trunk of a tree but had clearly been removed forcefully by a weather event some time ago. As I approached the tree and leaned round the back to peer into the hollowing stem, my gaze was met by the bright yellow and beady eyes of a Common buzzard who was probably perching in the hollow whilst on the lookout for its next meal. The few silent seconds of disbelief (probably on both accounts) were then abruptly brought to an end as the impressive Bird of Prey turned, spread its wings and silently glided away to an alternative (more private) tree nearby.
Heritage of the North York Moors
Our Linking Landscapes programme aims to connect fragmented woodland habitats and areas of high ecological value. Veteran trees (and their associated ecology) have an important role. Many of our most notable and veteran trees are visible today in fields and along dry stone walls and hedges as remnants/relics of historical field boundaries, they remain important features of complex habitat networks throughout the landscape and as part of the programme we’re planting new in-field and boundary trees to ensure that tree habitats remain even when the veteran tree itself has died.
But the biodiversity value of veteran trees within our landscape is something which we cannot replace in the short term. Many species associated with the habitats provided by these trees are specialists and depend on veteran trees for their survival, either directly (beetle larvae living within, and feeding on, the freshly decaying wood) or indirectly (birds and bats regularly utilise the hollows associated with veteran trees for nesting and roosting sites).
It is important that we plan ahead and attempt to provide the best opportunity for the development of future generations of old and veteran trees that we can.