A huge thanks to Burnham Beeches yesterday for hosting some of us for the day and showing us around the site. Below are some of the stand-outs from the day, which I am certain you will all appreciate!
The importance of functional units
As we can see in the below few images of a particularly striking beech pollard, very little of the structure of the tree needs to remain for the tree to persist as a living and functional organism. In this example, only one unit of vascularity supports a very small crown, though the beech is generally without significant fault. It could, potentially, persist in this state for many decades! Certainly, the two natural ‘props’ that support the crowd through a sort of tripod could, in their eventual failure, be the demise of this tree; assuming the functional unit cannot itself adequately support the crown. Depending on the rate of decay of this two ‘props’, this last vascular strip might (if decay is slow) – or might not (if the ‘props’ fail sporadically) – be able to lay down the necessary wood fibres for such mechanical support.
Reduction work on lapsed pollards
There comes a point where one has to make a decision – for what reason is a lapsed pollard being managed? If it is to be managed for the provision of habitat then the major failure of the structure might not be an adverse occurrence (to a degree!), though if the intent is to retain the pollards for as long a period as is at all feasible then it might be necessary to undertake quite extensive reduction work, in order to reduce the mechanical loading upon the old pollard head. As can be seen from the below beech, heavy reduction work has taken place and the crown architecture / good number of ripe buds that remain below the pruning points will hopefully ensure that this lower crown will function very effectively. Of course, where lapsed pollards don’t have this lower growth then a heavy reduction might not even be possible, though where such low growth exists then it does provide for more effective means of management, with regards to reduction work of the crown.
Submerged deadwood for reptiles
A terrapin uses a large section of a mostly-sunken stem for sunbathing, in the centre of a large pond. Indeed, this section of deadwood is an effective tool for the terrapin, which allows it to be exposed to direct sunlight and isolated from potentially aggressive mammals (that includes humans – seriously). Improving the texture and heterogeneity of this aquatic habitat with deadwood is evidently important, therefore!
Artificial propping
As some of the old beech pollards are quite literally falling apart, safeguarding their structures against such cataclysmic failure is necessary, if their presence in the landscape is to be retained. For some, this involved reduction work, whilst for others it involves installing props to support either the enture tree or large / heavy parts of its structure. In the below two cases, we can see how props have been installed to stop the trees falling over completely.
Wood-decay fungi
As you’d very much expect from a place such as this, wood-decay fungi are found in relative abundance. Beneath, the best examples are shown – this includes less common fungi, which we also came across during the trip; or less common associations, as you’ll see for one particular set of photos!
Fomitopsis pinicola (red-banded polypore)
Along the stem of a beech, this single bracket of a very infrequently found (in the UK, anyway) wood-decay fungus, the red-banded polypore, resides. Adjacent to a colony of Bjerkandera adusta and above extensive swathes of Kretzschmaria deusta, exactly to what degree this fungus has secured the wood substrate is unknown, though the good thing is that it has produced a fruiting body and in sporulating!
Heterobasidion annosum (fomes root rot)
A common fungus but probably not one you see every day on hawthorn! Hidden beneath a branch ridden with Fuscoporia ferra (syn: Phellinus ferreus) and some leaves, a series of fruiting bodies were tucked away comfortably. Fungi love to throw curve-balls!
Ganoderma pfeifferi (bees-wax polypore)
Sadly, the host beech had recently failed, due to the decay caused by this fungus. With respect to the rot induced, the failure was seemingly a brittle one and thus the failure can be attributed to a significant loss of cellulose. The cross-section of the failed region also yielded some glorious ‘rosing’ patterns, which is something that has been seen in other cases of failure as caused by this particular fungus.
Fomes fomentarius (hoof fungus)
Found on both birch and oak, this species isn’t notably abundant in the south of England, where the pathogens Ganoderma australe / resinaceum / pfeifferi (in order of commonality) tend to be better suited. In the two instances shown below, fallen deadwood has provided the resource, which aligns with its colonisation strategy – that of awaiting stress / entire vascular dysfunction of an area or whole tree, before launching wide-scale colonisation activities.
Daedalea quercina (Oak mazegill)
Found quite frequently on dysfunctional wood of oak, this instance has provided the best sight yet of this species. As you can see, an oak monolith is utterly littered with fruiting bodies, which is genuinely a spectacular sight!
The arthropods are vast in terms of species, and include ants, beetles, butterflies, mites, moths, spiders, and so on. Therefore, covering the entire spectrum of arthropods in this section is impractical, though the general provisioning by trees will be outlined and species will be used to illustrate given examples.
Many arthropods are considered to be saproxylic in nature – they principally utilise dead woody material (both standing and fallen, in both dead and living trees) as habitat, for at least part of their life cycle, though they may also rely upon fungal sporophores associated with the presence of deadwood, as is to be detailed below (Gibb et al., 2006; Harding & Rose, 1986; Komonen et al., 2000). Of all the saproxylic arthropods, beetles are perhaps the most significant in terms of the proportion occupied of total saproxylic species worldwide (Müller et al., 2010), though saproxylic flies also feature in great numerical abundance (Falk, 2014; Harding & Rose, 1986).
Beetles may be either generalist or specialist in nature (on either broadleaved or coniferous hosts), and they will normally require a host with an abundance of deadwood (or large sections of coarse woody debris) usually over 7.5cm in diameter that resides within an area typically not heavily shaded (Müller et al., 2010; Siitonen & Ranius, 2015). This may be, in part, due to many beetle species (in their adult stage) requiring nectar from herbaceous plants, which would be lacking in woodland with significant canopy closure (Falk, 2014; Siitonen & Ranius, 2015). This means that veteran trees amongst wood pasture and parklands (including in urban areas) may be particularly suitable (Bergmeier & Roellig, 2014; Harding & Rose, 1986; Ramírez-Hernández et al., 2014; Jonsell, 2012; Jørgensen & Quelch, 2014), though this is not at all a steadfast rule as species may also be found abundantly in (perhaps more open) woodland, and particularly where there are large amounts of veteran trees and deadwood – around 60 cubic metres per hectare, according to Müller et al. (2010). Granted, they are found particularly in older (mature to veteran) trees, including within cavities that possess wood mould, water-filled rot holes, dead bark, exposed wood, sap flows, fruiting bodies (of fungi and slime moulds), mycelia of fungi, dead branches, and dead roots (Carpaneto et al., 2010; Falk, 2014; Harding & Rose, 1986; Siitonen & Ranius, 2015; Stokland et al., 2012). Beetle species may also not necessarily associate preferentially with a species (or group of species), but with the conditions aforementioned that are present within a tree (Harding & Rose, 1986; Jonsell, 2012). At times, preferable conditions may be an infrequent as one veteran tree in every hundred (Harding & Rose, 1986).
A veteran oak tree that is of prime habitat for a variety of organisms.
Despite this, species preference is observed. For broadleaved obligates, heavier shade may be more necessary, and in such instances there is a closer affinity of the beetles with fungal mycelium. Because fungi tend to produce more mycelium in cooler and more humid conditions (though this does, of course, vary with the species), the broadleaved obligates may therefore be found normally in greater abundance where conditions are more suited to fungal growth, and their presence may thus be associated with a canopy openness of as little as 20% (Bässler et al., 2010; Müller et al., 2010). This is, of course, not a steadfast rule, and many open wood pastures may support a great abundance of saproxylic beetles (Harding & Rose, 1986).
It is also important to recognise that many species of saproxylic beetle are reliant upon particular stages of the wood decay process. For instance, species that require fresh phloem tissue will only be able to colonise briefly in the first few summers following on from the death of the phloem tissue (Falk, 2014). Other species require significantly-decayed wood in a particular micro-climate, and even of a particular tree species (Harding & Rose, 1986). There also exist intricate associations between species of fungi and saproxylic insects. Inonotus hispidus, which is usually found upon ash, is the habitat for Triplax russica and Orchesia micans, whilst the coal fungus (Daldinia concentrica), also oft found upon the deadwood of ash (Fraxinus excelsior), is the main provider of habitat for Platyrhinus resinosus (Falk, 2014). The birch polypore (Fomitopsis betulina) is also host to numerous species of Coleoptera (Harding & Rose, 1986); as is the polypore Fomitopsis pinicola (Jonsson & Nordlander, 2006; Komonen, 2003; Komonen et al., 2000). This means that these species may be found where there is a suitable population of the fungus’ host species, where sporophores are present and will likely fruit again in the future, across numerous trees, and for many years. Most beetle species rely on oak more so than other tree species however, as oak generally lives for much longer and thus provides a wider array of different micro-habitats, and possesses increased compositional complexity as a result (Harding & Rose, 1986; Siitonen & Ranius, 2015).
A fruiting body of Inonotus hispidus on apple (Malus sp.). This fungus not only creates habitat in the wood that it degrades but also is a direct habitat through its sporophore.
Therefore, the loss of suitable habitat through active management programmes (including logging, and felling trees for safety reasons in urban areas) will have a very adverse impact upon saproxylic beetles, though also certain species of moth, and even species associated with saproxylic insects, including parasitic wasps, solitary wasps (which use beetle bore holes for habitat), and predatory Coleoptera (Harding & Rose, 1986; Komonen et al., 2000). Curiously, research by Carpaneto et al. (2010) concluded that trees that were ranked as the most evidently ‘hazardous’ were host to the most saproxylic beetle species, and their removal would therefore have a drastic impact upon local populations. Similarly, fragmentation of woodland patches suitable for saproxylic populations has led to a decline in the meta-populations (Grove, 2002; Komonen et al., 2000), as has deadwood removal in a managed site itself (Gibb et al., 2006). Interestingly, though not surprisingly, ‘deadwood fragmentation’ also has an adverse impact upon saproxylic insect populations (Schiegg, 2000).
Both ants and termites also benefit from the presence of deadwood. With regards to both, nests will usually form at the base of a tree or at an area where there is at least moderate decay – enough to support a viable population (Jones et al., 2003; Shigo, 1986; Stokland et al., 2012). Ants and termites both follow CODIT (compartmentalisation of damage in trees) patterns in relation to how their nests progress, and thus their territory will increase as fungal decay propagates further into the host. Ants will not feed on the decaying wood of the host however, and will simply use the decaying site as a nesting area. Conversely, termites will feast upon decayed wood and essentially control (perhaps by slowing down) the spread of fungal decay in a manner that provides as much longevity of the host as possible for a viable nesting site (Shigo, 1986). In tropical rainforests, termites are in fact considered to be one of the principal means of wood decomposition (Mori et al., 2014), and thus the provisioning of deadwood habitat is absolutely critical. Without decaying wood within trees therefore, ants and particularly termites will lack a potential habitat, and thus where a stand is actively managed populations may be markedly reduced (Donovan et al., 2007; Eggleton et al., 1995). Of course, termites are not necessarily to be desired when they are invading the wood structure of a property, and therefore deadwood is not universally beneficial (Esenther & Beal, 1979; Morales-Ramos & Rojas, 2001) – at least, when human properties are involved.
Ecologically beneficial? Yes. Economically beneficial? No. Termites can – and do – damage timber-frames buildings, as is the case here. Source: Pestec.
The presence of deadwood may also be beneficial for ground-nesting and leaf-litter dwelling spiders, which can utilise downed woody debris (particularly pieces with only slight decay) for both nesting and foraging (Varady-Szabo & Buddle, 2006). In fact, research by Buddle (2001) suggested that such spiders may more routinely utilise downed woody material when compared to elevated woody material (dead branches and telephone poles) because of the greater array of associated micro-habitats, and particularly at certain life stages – such as during egg-laying, for females (Koch et al., 2010). Furthermore, as fallen woody debris can help to retain leaf litter (or even facilitate in the build-up leaf litter), spider populations are more abundant and more diverse in sites where such woody debris is present (Castro & Wise, 2010). Therefore, where woodlands are managed and areas are clear-cut, spider populations may be markedly reduced in terms of the diversity of species. However, generalist species may benefit from the amount of cut stumps (Pearce et al., 2004). Curiously, Koch et al. (2010) suggest that spiders may perhaps benefit from woodland clearance, because the vigorous re-growth of trees and the higher light availability to the woodland floor (promoting herbaceous plant growth) increases the abundance of potential prey. Despite this, old-growth species will suffer (Buddle & Shorthouse, 2008), and thus the population structure of spider populations may dramatically change.
Soil mites are a further group that benefit from coarse woody debris, though also from hollows and holes throughout the basal region of a tree (including water-filled cavities), and from fungal sporophores and hyphae associated with wood decay (Fashing, 1998; Johnston & Crossley, 1993). Typically, termites will use fungi and insects found within the wood as a food source, and the wood structure itself will provide for an array of niche micro-habitats that are critical at different life stages of a mite. Certain mite species are obligates that associate with coarse woody debris exclusively, and may in fact only be associated with certain species’ woody debris. Additionally, mites may utilise woody debris and hollows within trees to parasitise upon other species using the ‘resource’, with both lizards and snakes being parasitised by mites following their frequenting of such resources. Beetles may also be parasitised, though the mite in such an instance may use the beetle as a means of entry into woody debris (Norton, 1980).
It is not just deadwood that arthropods will utilise, however. Foliage, both alive and abscised, is also of use (Falk, 2014). For example, the ermine moth (Yponomeutidae) will rely upon the living foliage of a host tree as a food source, and the bird cherry ermine moth (Yponomeuta evonymella) is one example of this. During late spring, larvae will fully defoliate their host Prunus padus, before pupating, emerging, and then laying eggs upon the shoots ready for the following year (Leather & Bland, 1999). Many other moth species will, during their larval stage, also behave in such a manner and thus defoliate their host – either entirely, or in part (Herrick & Gansner, 1987). Other species may alternatively have larvae mine into the leaf and feed upon the tissues within (Thalmann et al., 2003), such as horse chestnut leaf miner (Cameraria ohridella). Flies, including the holly leaf-miner (Phytomyza ilicis), will also mine leaves in a similar fashion (Owen, 1978). Ultimately however, the same purpose is served – the insect uses the living tissues of a leaf to complete its life cycle, and fuel further generations.
Bird cherry ermine moth having defoliated an entire tree. Source: Wikimedia.
Fallen leaf litter, as briefly touched upon earlier when discussing spiders, may also be of marked benefit to many arthropods. Ants, beetles, and spiders are but three examples of groups that will utilise leaf litter as a means of habitat (Apigian et al., 2006). Beetles will, for instance, rely upon leaf litter to attract potential prey, though also to provide niche micro-climates that remain relatively stable in terms of humidity, light availability, and temperature (Haila & Niemelä, 1999). Their abundance may, according to Molnár et al., (2001) be greatest at forest edges, perhaps because prey is most abundant at these edge sites (Magura, 2002). Of course, this does not mean that edges created through artificial means will necessarily improve beetle populations, as research has shown that there are few ‘edge specialists’ and therefore populations usually will go into decline where there has been significant disturbance. Unless management mimics natural mortality events of forest trees, then constituent beetle populations may thus suffer adversely (Niemelä et al., 2007).
With regards to ants, Belshaw & Bolton (1993) suggest that management practices may not necessarily impact upon ant populations, though if there is a decline in leaf litter cover then ants associated with leaf litter presence may go into – perhaps only temporary (until leaf litter accumulations once again reach desirable levels) – decline (Woodcock et al., 2011). For example, logging within a stand may reduce leaf litter abundance for some years (Vasconcelos et al., 2000), as may (to a much lesser extent) controlled burning (Apigian et al., 2006; Vasconcelos et al., 2009), though in time (up to 10 years) leaf litter may once again reach a depth suitable to support a wide variety of ant species. However, the conversion of forest stands into plantations may be one driver behind more permanently falling ant populations (Fayle et al., 2010), as may habitat fragmentation (Carvalho & Vasconcelos, 1999) – particularly when forest patches are fragmented by vast monoculture plantations of tree or crop (Brühl et al., 2003). The conversion of Iberian wood pastures to eucalyptus plantations is one real world example of such a practice (Bergmeier & Roellig, 2014).
Also of benefit to many arthropods are nectar and pollen. Bees, beetles, butterflies, and hoverflies will, for instance, use nectar from flowers as a food source (Dick et al., 2003; Kay et al., 1984), and generally (but not always) a nectar source will lack significant specificity in terms of the insect species attracted (Karban, 2015). Despite this, different chemicals secreted by different flowers, and the toxicity of certain nectar sources to particular insects, means certain tree species may only be visited by certain insect species (Adler, 2000; Rasmont et al., 2005). Tree diversity may therefore be key to sustaining healthy insect populations (Holl, 1995), and where species may prefer to frequent herbaceous plant species the presence of a diverse woodland canopy above may still be very influential (Kitahara et al., 2008). This may be because a diverse array of woody plant species increases the diversity of herbaceous species. At times, pollen may also be a reward, as may (more rarely) a flower’s scent. Karban (2015) remarks that all are collectively dubbed as ‘floral rewards’.
References
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Woodcock, P., Edwards, D., Fayle, T., Newton, R., Khen, C., Bottrell, S., & Hamer, K. (2011) The conservation value of South East Asia’s highly degraded forests: evidence from leaf-litter ants. Philosophical Transactions of the Royal Society of London B: Biological Sciences. 366 (1582). p3256-3264.
See part II of this series on state forestry in Zimbabwe here.
Whilst slightly less economically-driven in the direct forestry sense, the development of state forestry practice in the mountainous regions of France – principally the Alps and Pyrenees – provides for another example into how state forestry has been met with civil unrest. Traditionally, the agrarian peasantry of the mountainous regions of southern France had maintained a close connection with the forest (comprised of species including silver fir Abies alba, beech Fagus sylvatica, oak Quercus robur / Quercus petraea, pine Pinus mugo, and spruce Picea abies), using it, for example, as pasture for local breeds of cattle and sheep, for medicinal purposes, or to provide for the necessary timber and firewood for sustaining a somewhat comfortable existence. Forest was also cleared for agricultural purposes, as was it harvested for charcoal to fuel the developing ironworks industry. Management typically adopted what is defined as jardinage, which entails the management of the forest as if it were a form of garden – felling was irregular, and there was no ‘scientific’ approach to forest management; simply because it didn’t need to be, as the forest was managed for subsistence purposes by the peasantry. Therefore, the forest – as well as the pasture lands surrounding – was understood as belonging to the peasantry, sometimes on a private basis but more often on a communal one, and its existence was critical for sustaining their way of life. Consequently, when the state began to encroach upon this assumed right of forest and land ownership, for a multitude of reasons, such an intent was met with marked vitriol.
Forest being cleared for charcoal production. Source: Z-Blogs.
Whilst the bulk of the protest occurred during the period of 1860-1940, it is important to recognise the political dynamics that led up to this tumultuous period of French history, and therefore one can begin observing how the state interfered in the management of forests (both lowland and upland, as one combined entity) as far back as 1215. From 1215 through to 1800, a series of Ordinances had governed the use of the forest across France. Different Ordinances meant different limitations were in place, though in principal royal and ecclesiastical forests had limited potential use by the peasantry. Largely-speaking, such Ordinances were geared towards the management of lowland forests of France, and not to the mountainous ones referenced here. Therefore, the Ordinances, and in particular the 1669 Ordinance, did not hold much clout in the mountainous regions of southern France, and were therefore intentionally ignored – or simply not enforced – by and upon the peasantry, respectively. Nonetheless, forestry did occur in France, and this prior period is detailed by Matteson (2015).
However, come the 18th and 19th century, as the state observed the forests of the mountainous regions slowly dissipate as a consequence of continued degradation by the peasantry, and the adverse environmental impacts of this (soil erosion of upland areas, large-scale flooding in critical lowland agricultural areas, and so on), it sought to alter its modus operandi with regards to the upland forests. However, military efforts and the improvement of infrastructure also demanded timber, which must be provided from national forests. Most importantly, because the state did not trust the peasantry to restore the mountainous areas to high forest cover, it pursued the acquisition of territory to undertake such reforestation itself. Such a process began in 1790 when the state initiated the accumulation of ecclesiastical land, though the Rural Code of 1791 (put in place following the French Revolution that ended earlier that year) prohibited the state from acquiring communally-owned land, which limited its capacity in developing large tracts of mountainous land for reforestation purposes. However, come 1801, the Administration des Forêts was established, with the main aim of supplying timber for shipyards – this birth of a new era in state forestry soon led to the establishment of the Forest Code in 1827, which adopted a much broader set of aims.
Artwork depicting the Pavillon de l’administration des forêts in Paris, 1878. Source: Wikimedia.
The Forest Code of 1827 was a particularly undesirable piece of legislation, in the view of the mountainous peasantry. The Code allowed the state to acquire communally-owned land with relative ease, and forbade pasturing in forests, the gathering of firewood, and the felling and extraction of particular trees. It also established the footings of future reforestation efforts. Crucially, the Code did not recognise the huge distinction between mountainous forests and lowland ones. In this sense, the traditional way of the mountain regions was directly in opposition to the Code. The situation was further exacerbated by the heavy policing that came with the introduction of the Forest Code. Forest guards, employed by the state, were instructed to arrest individuals for crimes that were once not even considered crimes (and by the peasantry still were not), and prosecutions for these crimes (however little – such as illegally grazing one cow outside of permitted zones) in court were met with fines and jail time. Therefore, by 1829, the electrical social and political standing was so severe that mountainous peasants began to revolt. One notable example of such revolt, which was certainly violent in many aspects, was the War of the Demoiselles (1829-1832) in the area including Massat, which saw male peasants dress up as women and ransack privately-owned and state-owned forests, and also attack the much-maligned forest guards and noblemen (see Sahlins, 1994). The famine of 1848 also saw many peasant revolts in these forests, for the limited usage of the forest was certainly a driver behind the extent of the famine of the mountainous peasants.
In 1851, when the state voted to relax the control of lowland forests to promote better agricultural practice, the mountainous forests took a further step towards state ownership and management. The state saw agriculture as highly important for France’s economy, and therefore considered the mountains to be of supreme importance in safeguarding lowland plains from the throes of flooding (as so pertinently demonstrated by the horrific floods of the 1840s). Subsequently, the mountain slopes had to be reforested, as their current state was far from sufficient in the aim of having such upland forests protect the lowland plains from harm. As ascertained, because the state was not trusting of the mountainous peasantry, it pursued reforestation through its own means; as well as mandating land owners to reforest their land that, if refused by the land owner, resulted in them forsaking at least half of their land to the state (who would then reforest it). Laws passed by the state in 1860 enabled for even more communally-owned upland land masses to be occupied by the state, which certainly aided in this reforestation effort; albeit to the huge detriment of the mountainous peasantry.
Moorland prior to afforestation with pine in the middle of the 19th century. Source: Abelard.
It was therefore this period, from 1860, when political tensions were reaching the proverbial boiling point between the state and the peasantry of the Alps and Pyrenees. After all, the attrition upon and erosion of their traditional customs had resulted in their way of life having to alter greatly if their agrarian existence was to remain tenable. Matters were made worse by the lack of inclusion of the peasantry in local decisions made on reforestation, and the exclusion of the very same peasantry from some – if not all – of the land upon which they made their living. In 1864, the state recognised the friction between the state and the peasantry, and made more lax the regulations of reforestation, allowing instead for some areas to remain as grassed pasture. 1870 also witnessed the close of the 1860 law, and the subsequent pursuit of new forest laws to protect the mountain slopes from erosion and flooding. Discussions began in 1873 to produce a new law, though it only were properly formalised as a new law in 1882, and was entitled Restoration and Conservation of Alpine Lands. Curiously, its title entirely omits the idea of reforestation, though the peasantry were just as wary of this new piece of legislation as the end goal of the state was no different to what it had been in 1860 – it was simply more inclusive of the needs of local peasants, and opted to pursue engineering solutions as well as natural solutions for the protection of mountain slopes. The law also restricted the state’s ability to acquire new land for reforestation, and mandated there be ample justification in purchasing communal or private land, and created a department known as the Restauration des terrains en montagne (or RTM). This department would largely be responsible for reforestation projects.
However, the constant change in leadership of the Administration des Forêts resulted in this approach (of being more accepting of the peasantry) lacking long-term commitment, as different forest managers approached the pursuit of reforestation and land acquisition in different manners; certainly, some approaches were far more militant, and the 1882 law didn’t always appear as being more lax than its 1860 predecessor. Therefore, whilst having ended in 1832, the War of the Demoiselles evolved into the Affair of the Mountains, for example. This new era of protest, which gained serious momentum after in the later periods of the 19th century, saw peasants adopt a progressively more political and legal approach to protest, culminating in the early 1900s with the local government being comprised of almost exclusively the peasantry. This approach was spearheaded in part, from 1870-1900, by Francois Piquemal, a peasant farmer who promoted rebellion against forest law and the innate right of the peasants to the lands they lived within and worked upon. In response to this political uprising and modernisation of peasant protest, the French state quelled quite extensively its pursuit of reforestation in the area, having realised that state forestry in a location so opposed to it – and with a peasantry willing to hamper quite zealously any efforts made to create forest cover – was an exercise in futility.
Partly as a consequence of the association of the Administration des Forêts in the late 19th century with a lack of consideration for peasants, though also because the administration also became responsible for France’s waters in 1896, its organisational name was changed to Eaux et Forêts in 1898. Such a name change also reverted the administration’s name back to what it was prior to 1801, thereby reflecting a more traditional approach to state forestry and land management. Despite this homage to traditionality, the Eaux et Forêts (principally the RTM) pursued the acquisition of land (communally- or privately-owned) for the state en masse, and by 1900 a total of 163,000 hectares had been secured and another 172,000 hectares were highlighted for acquisition. This almost industrial rate of conversion to state-owned land had ramifications for the peasantry of the mountains, and by the project was falling short of its targets – in part, because of protests.
Regardless, the state continued with its aim of obtaining land for reforestation, and therefore in 1913 the Audiffred law was passed, and enabled the state to impose more controls upon privately-owned forest land. Scope even existed to allow the RTM to manage the forest on behalf of the land owner, with the interest of protecting lowland plains from the throes of flooding brought about from the mountains. In the same year, to supplement this new law, the state’s means of managing communal lands was enhanced. A revision potentially triggered initially by the unrest in the late 19th century, the new law developed into one of allowing the Eaux et Forêts to have much greater control over the management of land in upland areas. Whilst the 1882 law had not allowed the state to acquire land for the purpose of reforestation unless there was marked justification for doing so, this new law gave the state scope to acquire any land it desired.
A century of difference on mountain slopes within the Pyrenees. Source: Revuelto et al. (2016).
The onset of World War I, some months later in 1914, relayed the enactment of the 1913 laws, though also led to the laws being supported by a further wave of legislation and political standing pertaining to forest management, which would have repercussions for the rural Alpine and Pyrenean communities. The evident frenetic demand for timber for the war effort rapidly demanded additional resources beyond what the RTM could provide, and therefore in 1915 the Service forestier aux armées (SFA) was created the help with the felling and transport of timber to the front line. By 1917, the Comité général des bois also was born, for similar purposes. In late 1918, when the war has come to a close, a total of over 600,000 hectares of forest had been literally consumed in France, and it was estimated that there was a deficit of 1,636,000 cubic metres of timber each year. The decimated landscape, courtesy of persistent shelling and military action, also meant many standing forests were scarred, and areas to be reforested damaged significantly. Consequently, the Eaux et Forêts and RTM very rapidly earmarked massive areas for replanting, and the mountainous tracts of land did not escape this process.
Initially, the RTM entertained the idea of planting up coniferous forest stands within the Alps and Pyrenees, though the documented evidence and evidence gained after some initial planting projects soon lay waste to this pursuit – the conifers simply could not grow desirably, given an array of climatic and geological factors. Therefore, notably after the formalising of the Chauveau law in 1922, reforesting projects were undertaken under the banner of ‘protective forestry’. In short, the aim of reforestation reverted back to the initial aim from the century before, though with an added impetus: the lowland areas below the slopes were now becoming more heavily industrialised and infrastructure was better, and therefore protection was even more necessary as the costs associated with flooding would be even greater. Not only did the new law drastically limit the ability for agrarian peasants to undertake grazing, the felling of trees, and so on, but it also gave the RTM the power to very swiftly obtain land and reforest areas earmarked for planting. After consultations in 1925 over land masses to be planted, despite being near universally met with unease by rural councils and peasants, projects began as soon as 1926. This resulted in many peasants losing access to their land, and in turn a rural exodus began; such an exodus paved the way for what was to come.
Quite simply, following the exodus, those who remained became more reliant upon the Eaux et Forêts for employment and financial aid; such a reliance was accentuated by the economic plights of the 1930s. Furthermore, within the same decade, and also because of the exodus of rural peasants, the state passed laws recognising the importance of traditional customs in rural communities. Certainly a means of trying to safeguard rural economies and communities, laws in fact allowed – and even promoted – jardinage, which had historically been frowned upon by foresters. Peasants could also collect firewood from state forests, as could they gather fodder for animals, and timber from deformed branches (collectively known as sarclage). Ultimately, as long as the forests remained in tact and could fulfil their purpose for protecting the lands below, peasants had more freedom to practice their traditions. Even pastures were opened up for grazing by sheep and cattle, and some foresters also allowed pastoralists to graze their sheep or cattle within the forest itself by 1936. As a result, peasants began to warm to the idea of state forestry (and the role the forests themselves played in rural life), and the Eaux et Forêts began to warm to the peasantry – quite ironically, one could remark, given the centuries of almost unsolvable animosity between state and mountain peasant.
This decade also witnessed the decline in power of the Eaux et Forêts, however. By 1935, it had 25% fewer staff than it had in the preceding decades, and peasants were calling on the organisation to employ more foresters to enable communal forest management projects to be overseen properly. For the foresters that remained within the organisation, though also those that worked for private landowners, the situation was concerning. Therefore, many had begun to join organisations dedicated to promoting tourism within the French mountains (such as the Société des Amis des Arbres and Touring-Club), as these organisations championed the idea of reforestation upon the slopes of the mountains – notably on communal land abandoned following the outward migration of pastoralists. Since the last decade of the 19th century, such tourism had begun to gain popularity, and by the 1930s the Eaux et Forêts had formed partnerships with many of these organisations – partnerships that also provided funding, from the Eaux et Forêts to the tourist organisations, for the purpose of reforestation projects. The main aim of such reforestation, in the eyes of the tourist organisations, was that their clients (often well-off individuals) wanted to experience unadulterated nature, away from civilisation (notably the peasant under-class). Consequently, this is what the organisations would seek to provide.
Alongside tourism came industry, and in turn a changing demographic. Because the well-off tourists didn’t want to experience the ways of the traditional peasantry, and compiled with the fact that the peasantry could not provide the services demanded by the tourists, businessmen migrated into the mountains and the peasantry further migrated out. In spite of organisations such as the Société Française d’Économie Alpestre and the Fédération Pyrénéenne d’Economie Montagnarde promoting pastoralism during the 1920s and 1930s – a pursuit even funded by the Eaux et Forêts up until 1937 – the rural exodus did not wane, and the original aim of reforestation on the mountain slopes was fulfilled through the natural regeneration of forests on abandoned pasture. Traditional custom of the French mountain slopes thus became a practice of novelty, undertaken only by a few and relegated to the halls of memory for many.
Yesterday, the Ancient Tree Forum went to Wimpole, which is a 2,000+ acre estate owned by the National Trust, just south west of Cambridge, UK. Led by the head forester of the site, the day took us around a great portion of the estate, where we were shown not only old trees and their importance for saproxylic invertebrates (including many rare coleoptera and diptera), but also an ash woodland with coppice regeneration being battered by ash dieback (Hymenoscyphus fraxineus) and some woodland-borne elms enduring the devastating Dutch elm disease (Ophiostoma novo-ulmi).
Whilst the day itself began mid-morning, I – as usual – arrived very early, in order to explore. My aim was, principally, to find fungi, and I was certainly not let down in this regard, as you will see in the collection of images at the end of this post! More broadly, walking through the fields being grazed by both cattle and sheep, complete with many mature, veteran, moribund, and dead trees, in which some were evidently grazed around and others not, was a real treat. Such landscapes possess character orders of magnitude greater than standard park landscapes, which are basically lacking the grazing aspect that is culturally very important in the UK. Granted, not all parks can facilitate grazing, as people do lust for their formal parks, and letting grazing ungulates into specimen gardens is a great way to ruin the specimens (it’d be quite bizarre to see cattle roam across Kew Gardens), but those formalised gardens still lack the romantic feel of a proper English park.
During the guided tour itself, catching up with friends and acquaintances, listening to individuals contribute to matters regarding the management of Wimpole, and being around renowned experts in arboriculture, such as David Lonsdale, always means there’s things to talk about and much to learn. The intricacies of fungal associations with specific host trees, the destructive power of oak mildews, and the grazing of animals treated with veterinary medicines in the rhizosphere of mature and veteran trees, are not issues people would typically entertain, though in the setting of Wimpole all such discussions were completely contextual and highly valuable. The option of pollarding trees to manage for overhead power lines in the rural landscape might also make for interesting conversations in 400 years time, assuming the trees are still around and pollarded regularly. A far cry from why man traditionally pollarded trees, no doubt!
For those of you who are UK readers, please do check out the Ancient Tree Forum, and see if there’s a group local to you. For those not in the UK, perhaps there are similar organisations, and if not then perhaps even start one!
And now, for the myriad of photos (mainly of fungi on trees – who’d have guessed)…
A view of the house at Wimpole, which overlooks an impossibly long undulation of hills lined, either side, with trees. Visit yourself for a view of the avenue!A view into the grazed hills of the Wimpole estate, complete with dozens of mature and veteran trees – oaks, horse chestnuts, walnuts, limes, sycamores…Two lovely mature oaks (Quercus robur). The one on the right is at least 400 years of age, according to map records.Before we get onto fungi, here is the Devil Squirrel high up in a yew tree.
I have segmented the below pictures into different sections, each with a title stating the fungus and the host.
Perenniporia fraxinea on Quercus robur
At the edge of a field, near to the main car park, sat this mature oak.Hurdling fences is good exercise.Tucked away snugly between two buttress roots!Churning out white spore galore!A little cross-section reveals a trama that is a light brown colour, and a tube layer a darker shade of brown. 50 shades of brown, perhaps? Just a little less exciting, for most…A close view of the context, for those keen to see what Perenniporia fraxinea looks like inside.
Pseudoinonotus dryadeus on Quercus robur
A wonderfully broad oak, which recently shed a huge limb.The shed limb can be seen to the left, though we can also spot the Speudoinonotus dryadeus lagain between buttresses.Certainly a mature bracket, this will likely begin to senesce soon.A look from another angle, just so we can appreciate how awesome this fungus looks!
Cerioporus squamosus (syn: Polyporus squamosus) on Aesculus hippocastanum
On this small knoll, are a few horse chestnuts. The one on the left is the one we need to pay attention to, because……it is host to dryad saddle!Growing out from a branch wound, which may well have been the entry point for the spores in the past, too. The choice of emerging from wood not covered by bark is important, as not only may the fungus not be able to degrade the highly-suberised bark, but even if it could, producing fruiting bodies in areas lacking bark is far more energy-efficient.Looking more closely, we can see how the stipes support the fruitiing bodies.
Rigidoporus ulmarius on Aesculus hippocastanum
A grand horse chestnut stands proudly in this formal area.And boasts an equally grand Rigidoporus ulmarius!Notice the white spore and colourations that liken it slightly to Perenniporia fraxinea. However, the context is different, as we will see……with Rigidoporus ulmarius, the trama is almost pure white and the tube layer a cinnamon-orange colour.Here’s another small one on the same tree.And another one, for effect!
Inonotus hispidus on Juglans regia
Exhibit 1 – a modestly-aged walnut.Exhibiting a modestly-decimated Inonotus hispidus……okay, maybe massively decimated – and old!And a second one, further up the stem!Peeking out from between cracks in the corky bark.Exhibit 2 – another walnut, of probably identical age.Almost deja-vu, here…!Looking up into the heavens.When you stare into the abyss, the abyss stares back…
Inonotus cuticularis on Fagus sylvatica
Such a beautiful beech tree. Surely it couldn’t be tarnished by wood-decay fungi!?It did a good job hiding it, but we found it!Say hello to the internet, Inonotus cuticularis!Somehow I managed to get this photo with my brick of a spare camera. A curious arrangement of decked and small sporophores.A close-up shot of some chocolate gateau, for good measure. Extra chocolate sauce.A cutting someone managed to grab!
Arboriculture 