1. Introduction
Some 25 years ago, Chris Read published a paper here on ‘Ancient New Forest Trees’ with the following abstract:
“The New Forest is internationally important for ancient trees. It has nearly twice as many large oaks and beeches as have been recorded in earlier surveys. Some specimens of other trees, particularly holly, are also ancient. Estimating the ages of trees, especially pollards, is difficult as it depends on management history”.
Chris Read’s paper built on earlier work by Nicholas Flower (published in 1983) and included detailed measurements of ancient beech and oak trees; the focus was on the largest trees, i.e. those with a girth exceeding 5.8m, and their listing helpfully included a detailed grid reference and an assessment of whether they were pollards or maidens (unpollarded).
Today, the biodiversity value of ancient trees in the New Forest is widely recognised, both when they are alive and when they are dead and decaying (particularly for wood-rotting fungi and invertebrates). In addition, ‘citizen science’ initiatives such as The Woodland Trust’s Ancient Tree Inventory have raised public awareness and enabled online recording. However, there is also growing concern that climate change and an associated increase in extreme weather events, specifically summer drought and winter flooding, may be negatively impacting some tree species, including beech (e.g. see here).
To further investigate the recent status of ancient trees in the New Forest, Wild New Forest initiated a resurvey here of the ancient beech and oak trees listed by Chris Read in winter 2019/20, but this soon had to be paused due to COVID-19 restrictions. The baton was subsequently picked up by two local wildlife enthusiasts, Steve Laycock and Niall Bowcock, and below they document their methods and findings.
2. Methods
We set out in the footsteps of Chris Read in the late summer of 2023, with the aim of revisiting all the listed beech and oak trees. We walked approximately 100 miles (some 200,000 steps) while conducting the resurvey, and at one stage removed over two dozen ticks from our clothing! We are grateful for additional fieldwork support from Ade Parker.
A photographic record was taken of all the beech and oak trees surveyed, and the girth was taken as the smallest measurement below a height of 1.5m (see image below). It soon became clear that girth measurement is as much an art as it is a science, not only due to the presence of burrs and low-lying branches, but also access issues, where one side of the tree base can be a couple of metres above the lowest part, e.g. when it is in a banked hedgerow; others were challenging to access due to dense bramble scrub. Consequently, as noted by Chris Read, there can be quite significant differences in measurements of the same tree.
Steve and Niall measuring an ancient oak at Balmer Lawn
The background information for each species is largely taken from the Chris Read paper and updated here where necessary.
3. Oaks
3.1 Background
New Forest oaks are not large by British standards; girths of over 10m are recorded elsewhere in the country and the largest oak in Hampshire is the Oakleigh Oak at 10.74m. An oak can live for over 1000 years, but 600 years is more typical; the largest UK oak pollard may be over 800 years old. Oaks in parks and specimen oak trees can grow at twice the rate of oak in woodland.
Most the mature New Forest oaks were felled in the 17th and 18th century for ship building. In the 19th century, there were perhaps only three oaks in the open forest with girths of 5.2m or more. Today, there are in the region of 80. Pollarding was outlawed in 1698.
There are two native oak species in the New Forest, the pedunculate oak and the sessile oak; the latter species is more common in the north and west of the UK. The New Forest giants are pedunculate oak, with only a couple of specimens of sessile oak above 5.2m. It is hard to tell the age of New Forest trees from their girth alone. It is believed the largest and oldest oak in the New Forest is the Knightwood Oak - with an age estimate of between 380 and 500 years or older.
3.2. Resurvey results
A total of 44 oaks were measured during the resurvey, 40 of which were listed by Chris Read. Five oak trees measured over 7m and a further 25 between 6-7m, including a previously unrecorded oak: the Strange Oak at 6.3m.
An ancient oak with abundant burrs in Undersley Wood
Most of the oaks were standing and healthy, and just four were dead - the Moyles Court Oak and Seaman’s Corner Oak were possibly killed due to changing ground conditions and/or management activities associated with adjacent roads, while a Bramble Hill oak had snapped at a height of 3m and a Pinnick Wood oak appeared either diseased or poisoned (along with four other younger oaks nearby).
The largest New Forest oak remains the Knightwood Oak, a pollard now measuring 7.65m; closely followed by the Adam Oak, a maiden and presumably much younger tree at 7.5m. We initially measured the Adam Oak at 7.7m; we then returned and it took three of us 20 minutes, with some interesting acrobatics and engineering solutions, to get the measurement of 7.5m. The original reading would suggest a faster growth rate than the Knightwood Oak as might be expected for a younger tree; the second, perhaps more accurate measurement, suggests a slower rate. This highlighted the difficulty of collecting meaningful data on growth rates.
The Knightwood Oak, the largest ancient oak tree in the New Forest
4. Beeches
4.1. Background
Beeches are not very long-lived trees, typically lasting about 250 years. They are thirsty trees and suffer in drought but will not tolerate waterlogged soils, in part because they have widely spread but shallow roots. They also tend to die quickly when fungi and/or insect damage reaches a critical level, leading to ‘beech snap’ whereby the trunk snaps in the basal few metres. Nationally, very few beech woods have a full range of ages as almost all of them have been managed in some way.
The largest dated beech maidens were planted in 1680. Chris Read reports that the largest known maiden in the country was 6.7m and only 28 recorded larger than 5.8m. Before the 1698 Pollard Act pollard trees were lopped for fuel. After the Act firewood for commoners seems to have been supplied by felling maiden trees. About 250 beeches, mostly dead or decaying, were cut annually in the early 1870s. Felling for commoners’ firewood stopped in 1920 but dangerous trees were sold until 1970. Read writes: “There are probably more ancient beech pollards in the New Forest than anywhere else in the world.” Pollards are longer lived than maidens - “ageing begins from the date of the last cutting”. The oldest beeches have now not been pollarded for over 300 years and the biggest ones will be over 400 years old.
4.2. Resurvey results
Of the total of 34 beeches recorded by Chris Read, 21 were recorded as fallen or dead in our resurvey, and a further two partially collapsed, giving a failure rate of around 65% in 25 years. The failure rate was closer to 80% for the very largest trees, e.g. of the 16 beeches over 6m recorded by Chris Read, we found 11 were fallen or dead, and a further two partly collapsed. Just two of the original beech trees listed by Nicholas Flower in 1983 remain, at The Knowles and Parkhill Wood.
An ancient beech pollard at The Knowles
We spent many hours unsuccessfully trying to find listed beech stumps in the bracken, including trees which Chris Read describes and enthuses about. Of those left standing, several were a focus for our early summer survey work on Green Forest Hoverfly Caliprobola speciosa. As beech trees collapse it is quite usual for large gaps to appear in the canopy, allowing sunlight to hit the forest floor, which benefits warmth-loving invertebrates.
A collapsed ancient beech at Mark Ash Wood
With the exception of one maiden (now fallen), all the beech trees listed by Chris Read were pollards. 326 years after pollarding was outlawed, the giant beech pollards now appear to be rapidly disappearing from the New Forest.
5. Summary
Our assessment of the changing fortunes of ancient beech and oak trees over the last 25 years is broadly consistent with that of Chris Read, who noted that the rate of decline of ancient beech trees in the latter part of the 20th Century was much higher than that for equivalent sized oak trees. For example, Nicholas Flower recorded ten beech trees over 6m in his 1983 list, of which Chris Read recorded four as having fallen and two as partly collapsed in his 1999 list, a failure rate of 60% that is comparable to our figure of 65%. In contrast, our results indicate that most of the oaks listed in 1983 and 1999 are still standing.
It is interesting that Chris Read observes that the “droughts of 1976 and later years have finished off many old trees, while the canopies of the beech woods have been opened up by the great storms of 1987 and 1990”. It is also clear from his paper that the management history of the ancient and ornamental woodlands has had a significant influence on the number and distribution of ancient beech and oak trees that we see today. Chris Read also suggests that “in the next century the biggest danger, apart from bad management, is likely to be pollution”.
Disentangling past forest management from recent and ongoing impacts of climate change and pollution on ancient beech and oak trees in the New Forest is beyond the scope of this study, but our results further highlight the lower resilience of ancient beech trees compared to oak and provide a further baseline to assess future change. Our empirical data hopefully also provide useful context when assessing the status of beech-dependent species of high conservation concern in the New Forest, as well as topical discussions around beech and oak regeneration in the face of currently high grazing pressure from livestock and deer.
We are currently exploring options for appropriately archiving our photos so they may be available (together with our updated measurements) as a historical record in the future.
An ancient oak in Whitley Wood
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