ATF Trip to Fountains Abbey, North Yorkshire

Last month some of the tree survey team from AWA Tree Consultants attended the Ancient Tree Forum – Yorkshire and East Midlands local group field trip to Fountains Abbey, near Ripon, North Yorkshire. Here James Brown, senior arboriculturist at AWA, details what went down on the day:

Fountains Abbey is one of the largest and best-preserved ruined Cistercian monasteries in England. The abbey is situated within the wider Studley Royal Park, and together they are designated a UNESCO World Heritage Site. The site is around 800 acres and features include the abbey, 18^th century landscaped gardens, ruins of a Jacobean mansion, a Victorian church and a large deer park.

While the abbey and gardens are perhaps the main attractions at the site for most visitors, the veteran and ancient trees we were interested in were to be found predominantly within the deer park.

The day was hosted by the ATF Yorkshire and East Midlands local group, and we were guided around the site by park rangers from the National Trust who manage the site. We met at the car park by Studley Lake, which was surrounded by some easily overlooked ancient and veteran trees.

The first tree we were shown was a Field Maple situated right next to the car park. The tree’s crown showed signs of stress and we were told that this was likely due to the overflow car parking previously being allowed too close to the tree. This was now being managed by reducing the mowing area of the overflow car park to discourage parking close to the tree. A low wooden fence had also been erected around the tree to discourage both parking and visitors from spending prolonged periods of time directly under the tree’s crown. It was suggested that a future management option could be to lightly mulch around the tree – in gradually increasing quantities, to help the tree further recover from the ground disturbance and compaction caused by the parking.

We were then taken to an old Oak bordering the car park, situated between the car park and the main entrance to the abbey site. We were informed that this tree was one of only a handful of trees within ‘high target, high occupancy’ areas of the site, and as such was surveyed annually as part of the NTs tree risk management strategy. The crown of the tree showed significant dieback but was now recovering, with new epicormic growths visible throughout the crown. Pseudoinonotus dryadeus fungal brackets had previously been identified at the base of the tree and we were asked how extensive we thought the associated decay was. From afar there was little signs of decay, but on closer inspection and with some digging around the buttress roots, extensive basal decay became apparent, with the tree beginning to show the typical ‘Eiffel tower’ decay profile associated with the fungus. It was suggested that with the new epicormic growths in the crown, the tree would now better be able to tolerate crown future reduction works, as a possible management option to reduce the tree’s risk of failure.

The next tree was a very large, tall Oak situated between the car park and the lake. The park staff said that this tree was often missed even though it was one of the largest at the site, and in one of the busiest areas of the site. We thought that this could be because – from a distance – the tree didn’t have the typical form of a veteran or ancient tree; the crown appeared full and in good condition with no real signs of retrenchment. From afar the tree just looked like a typical mature Oak. It was only when we got up close that we realised how big and old the tree really was – it was at least 25m tall and the stem was between 5 and 6m in circumference!

Also situated close to the car park were several old Sweet Chestnuts which looked in good condition except for sporadic isolated patches of browning and dieback in the crown. One of the group correctly guessed this had been caused by grey squirrels, and on closer inspection squirrel damage was clearly visible at the base of the browning limbs, effectively ‘ringbarking’ the individual limbs. Discussions were had on the effectiveness and limitations of various squirrel management, with no obvious solutions available.

We then moved from the car park up towards St Mary’s Church. On the way we stopped at two neighbouring Oaks of contrasting conditions. Both trees showed extensive deadwood in the crown, but while one tree showed typical signs of retrenchment associated with ancient and veteran trees, the adjacent oak was more typical of crown dieback associated with decline – this provided a good example of the key difference between the two crown forms.

The lower crown of the older ancient oak tree had been heavily browsed by deer, as had most of the trees in the open park areas. Discussions were had about how deer can negatively impact the trees, not just the direct damage done from browsing the foliage, but also the ground disturbance and compaction thy cause around the base of the tree and the damage they can cause to the stems when rutting. Fences had been historically installed surrounding the stems of many of the trees in the park to deter the deer; the older steel fences became unsuitable as the trees mature with the embedding into the tree’s stems, which can prove very difficult to remove. The more recently installed fences were wooden, which would naturally degrade as the trees reached maturity. Yet with the site being a UNESCO World Heritage Site – even apparently simple changes like this involved additional complexity in terms of the landscape impact.

There was then a brief stop at a short, squat Lime. There was extensive decay to one side of the tree’s stem, with around half of the stem missing and it looked like the tree was defying gravity to remain standing. It was noted how the tree was almost missed as being of importance as it was initially only viewed from the ‘solid’ side – highlighting the importance of getting a full 360 view when inspecting trees. We were told to consider if the tree wasn’t decayed, what the full stem diameter might be and so how to better assess how old the tree actually was.

There were impressive views from St Mary’s Church down one of the main site access roads, to Ripon and Ripon Cathedral in the distance. The road was bordered by an equally impressive long avenue of Limes. The park staff told us that with these avenue trees – being in such a high profile area of the site – were used almost as a ‘bargaining chip’, i.e. providing they keep the avenue of Limes looking neat and tidy and what the general public would regard as ‘managed’ (remove deadwood and dead standing etc), this allows them to leave other less prominent areas of the site more unmanaged and naturalistic and so better for tree ecology.

Also by the church was a ‘phoenix tree’; a Sweet Chestnut which had previously failed, but instead of clearing away the stem, they had left it in situ and the previous limbs of the tree were now growing vertically from the fallen stem. This highlighted the importance of not rushing to tidy up sites with ‘failed’ trees as they may surprise us with their tenacity.

From the church we went on to see a Cherry which was likely one of the oldest in the country. The main stem of the tree was mostly dead and decayed but there was a large snapped limb that was clinging on to life. The value of the tree had warranted some fairly invasive interventions – cabling and propping – with the aim of giving the remaining limb – which was touching the ground- a chance to re-root.

A short distance from the Cherry was another very large Oak. The tree’s most interesting features were its hollow stem, a very large lateral primary limb, which had previously had some heavy-handed pruning, and some steel cabling within the crown. There was some extensive decay at the base, which was likely to extend into the union of the large limb. It was acknowledged that it may require further reduction works to avoid the limb failing; discussions were had regarding how much – if any – the limb should be reduced by, to reduce likelihood of failure while minimising wounding to the tree.

Overall, it was a fascinating day out that went by all too quickly. The National Trust rangers clearly understood the value and importance of the Ancient and Veteran tree resource they had and despite the complexity and tension between managing the visitors in a World Heritage Site, they were keen to be pro-active in doing what they could to sensitively manage the trees and surrounding land.