23rd November 2017
Book review: Ancient oaks in the English Landscape
David Lonsdale reviews Aljos Farjon’s book about how the oak tree has shaped the English landscape over the past thousand years.
Connections between past land use and the present-day distribution of ancient trees are the central theme of this book by Aljos Farjon, a botanist and author who is renowned for his work on conifers and who, in retirement, has turned his attention to ancient oaks.
Contributors to the Ancient Tree Inventory have recorded thousands of ancient trees in the UK. Aljos Farjon hit on the idea of using this information in order to explore in detail the relationships that were already known to occur between the distribution of England’s ancient oaks and the history of land use. By personally recording trees at many sites and by studying documented site history, he has confirmed the strength of these relationships, while also creating a very readable and fascinating book.
The book has a fitting title and a well-structured sequence of chapters, starting with “The life of an oak” from acorn to ancient tree. Chapter two looks at methods for estimating the age of oak trees, while chapter three is concerned with the general distribution of ancient oaks in England with reference to past land use. Chapter four focuses on particular categories of historical land designation, including royal forests, chases, deer parks, commons and medieval manors. Chapter five explains in detail how site history relates to the present-day distribution of England’s ancient oaks.
All who write about ancient trees face the difficulty of defining ‘ancient’ and ‘veteran’. The latter term has a wider meaning, including trees that are not chronologically ancient but that have ancient characteristics. This book includes information about all trees of girth ≥6 m, with additional statistics for those of girth ≥9 m, of which the author has counted 115 in England. Relatively small veterans are thereby excluded.
The author shows that oaks of ≥6 m girth are concentrated in several areas of England, including the Welsh Marches. He shows also that nearly all oaks of ≥9 m girth lie south of a line drawn from Shrewsbury (Shropshire) to Norwich but comments that this pattern might reflect growth rate more than age. With reference to historical records and maps, he confirms that ancient oaks in England occur mainly in areas that were subject to particular kinds of land use; namely royal forests, chases, deer parks (both medieval and Tudor), commons, medieval manors, together with features such as parish boundaries. In these areas, trees were generally either protected by law or kept for fuel-wood or fodder, including acorns or beech mast.
The author’s data analysis reveals something that had been suspected but not quantified; i.e. that a large proportion of ancient oaks are not pollards, contrary to conventional supposition. He argues that, even where other species were pollarded, maiden (i.e. non-pollarded) oak trees were often retained for large-size timber. In Tudor deer parks, where pollarding was often prevented, 84% of oaks of girth ≥6 m are maidens. Even on common land, 36.4% of such trees are maidens.
In Chapter six, “Ancient oaks in Europe”, the author provides information about a total of 96 oaks of girth ≥9 m elsewhere in Europe; fewer than England’s total of 115. There are, however, many oaks of girth ≥6 m in Sweden. The reasons why England has such a great share of Europe’s ancient oaks are discussed in the next chapter. These include a greater number of deer parks and a shorter history of extensive forest plantation. Further reasons, as suggested previously (Ted Green, pers. comm.), include a lower incidence of physically destructive wars and the desire of conservative-minded landowners to preserve private parkland.
Chapter eight, Ancient oaks in a pasture woodland context, concerns the park-like grazing lands in which most ancient oak trees attained their typically open-grown form. Ancient tree enthusiasts generally emulate the late Oliver Rackham in describing such areas as “wood pasture” but the author distinguishes between “pasture woodland” (translated from the Latin silva pastilis) as a physical entity and “wood pasture” as the resulting management regime. He considers evidence as to whether such areas existed prior to human intervention, concluding that they must have done so, given that various invertebrates and lichens depend on large, open‑grown trees. He points out, however, that closed-canopy forest must also have existed, according to evidence from trunks of ‘bog oak’ dating back 5,000 to 8,000 years.
Chapter nine, The most important oak sites, includes a map showing 23 sites and providing a wealth of information about each of them and their ancient oaks. Some of the site details appear also in earlier chapters but avoidance of repetition would have made the book harder to navigate.
Chapter ten, The biodiversity of ancient oaks, consists of contributions by specialists: Martyn Ainsworth on fungi, Pat Wolseley on lichens and Keith Alexander on invertebrates. The final chapter, Conservation of ancient oaks considers threats to the survival of these trees and proposes some solutions but without referring readers to the more detailed information provided, for example by Read (2000) and Lonsdale (2013). The threats include various diseases, including acute oak decline. Oak mildew, present since 1908 in England, is mentioned but is described as being “at most a growth inhibitor”. Deleterious land use is mentioned but without mention of associated changes in soil chemistry (e.g. involving nitrogen input and pH alteration).
The book is richly and beautifully illustrated with colour photographs and is reasonably priced for a volume of such size. It should therefore appeal to a wide readership with interests in the countryside, as well as to anyone with a particular interest in ancient trees. It is, however, also a valuable source of detailed information and will deserve the attention of managers, landowners and research workers for many years.
LONSDALE, D. (ed.) 2013. Ancient and Other Veteran Trees: Further Guidance on Management. The Tree Council, London, 202 pp.
READ, H. (ed.) 2000. Veteran Trees: A Guide to Good Management. English Nature, Peterborough, UK, 176 pp.
Ancient Oaks in the English Landscape was published in August 2017 by Kew Publishing, priced £30