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04/05/16. Fact #197.

 

Currently, I am on chapter 6 of Vera’s book Grazing Ecology and Forest History, and there’s a great sub-chapter (6.2.2) that explores the relationship between the Eurasian jay (Garrulus glandarius) and the oak. I learned a lot from reading this specific segment of the book, and thus hope that others also find the following information useful.

 

Firstly, one can certainly recognise that oak trees in Europe (Quercus petraea and Quercus robur) do not generally regenerate in woodland. Whilst acorns do germinate, after a period of usually less than a decade, they cease to be, as they are out-competed by shade-tolerant species, such as hornbeam (Carpinus betulus) and beech (Fagus sylvatica). Instead, oaks oft regenerate amongst thorny scrub (in grasslands, grazed areas, and within mantle and fringe vegetation bordering woodland), be the scrub comprised of hawthorn (Crataegus spp.), blackthorn (Prunus spinosa), holly (Ilex aquifolium), gorse (Ulex europaeus), or otherwise. In many an instance, one can perhaps wonder how the young oaks reached and regenerated within such scrub, and most notably so if there are no sizeable oaks within the immediate area. One explanation for this is, as explained by Vera, and courtesy of an array of sources, the Eurasian jay.

 

As an oak releases its fruit crop (acorns) into the harsh environment during September to November, the jay will collect many of the acorns (the healthy, ripe, good-sized ones, generally-speaking), and bury them at a distance from the tree that may vary from tens of metres to a few miles. When a jay collects only one or two acorns, it may bury them only a short distance from the point at which it gathered them from, but if the jay carries five or six acorns (in its gullet, throat, and beak – the largest being in its beak), then the acorns may be buried thousands of metres away. All of the acorns collected in one ‘trip’ will be buried in close proximity to one another, at a maximum spacing distance of around 15m (usually 0.5-2m spacings). At the level of a single jay, this dispersal of acorns may be relatively small, but when amplified to a group of jays 65 strong, research has indicated that (over the course of four weeks) up to 500,000 acorns may be dispersed. This dispersal is also very significant at distances from nearby oaks, with approximately 5,000 acorns per hectare when the nearest fruit-producing oak is around 200m away.

 

eurasian-jay-acorn-quercus.jpg?w=660&h=440

A Eurasian jay with an acorn within its beak. Source: Phil Winter.

 

Jays also have a strong preference of burying their acorns in open areas with loose soil. Usually, this will be open areas outside of forests within grasslands and amongst thorny scrub (this explains why oaks may pop up amongst thick scrub), though if substantial forest clearings manifest (due to tree mortality – normally courtesy of windthrow and the forest edge effect), then they too may be alluring sites in which the jay may cache its treasure. Interestingly, open areas complete with loose soil and areas of thick scrub are akin to medieval wood pastures, where grazing would have occurred.

 

oak-regeneration-mantle-and-fringe.jpg?w=660&h=880

This young oak is growing amongst bramble and gorse, within a heathland area, and beyond

the direct reach of a parent oak (meaning the acorn didn’t just fall into this spot). Thus, it is likely that it was buried by a jay.

 

Once the acorn has been buried by the jay, it will cover the site with soil and leaves, in order to hide it from sight. In order to re-find it, the jay will remember the vertical structures of vegetation in the immediate area – their memory of where they have planted acorns is, in fact, very good. Interestingly, a jay will only be able to find acorns it has buried – it will not be able to locate acorns buried by other jays, unless that other jay is also present at the time of digging up the acorn. Typically, the acorns they bury will be eaten throughout the year, though the months of April through to August mark the period when fewest acorns are dug up and eaten. This drop in predation by the jay fits in well with the period of acorn germination, with the stem emerging during May and the first few leaves unfolding in June.

 

This development of the small leaf crown co-incides with when jays will begin to search for acorns with a little more intent, as it is during this time that they will be feeding and training their young to fend for themselves. When a seedling (that is still green in the stem, and thus not lignified) is found from an acorn that the parent jay had buried, it will pull it up and eat the acorn, before depositing the little seedlng back into the ground rather crudely. Its young will, actually rather hilariously, mirror this behaviour, though with far less finesse, and pull up not only oak seedlings but anything else they find as well. This removal of the acorn does however not have a huge impact upon the oak seedling, as the strong and extensive tap root developed rapidly after germination means that the little oak seedling is securely anchored into the ground and can fend for itself, even if the acorn (provides energy for seedling growth) is lacking. Essentially, the uprooting is a trade-off that the oak tolerates well, so to be able to grow in the full sunlight conditions the jay opts to bury its acorns in (and where they will grow best, as the oak is not shade tolerant). Research has even shown that many oaks bear the scar of early uprooting by a jay, though since that time they have developed into healthy young trees. Importantly, this disturbance event only happens once (usually), as jays will only uproot small seedling that they buried. Jays are very ‘untrusting’ of ‘foreign’ or ‘alien’ acorns and oak seedlings, and thus will avoid them, by-and-large.

 

The symbiotic nature of the relationship between the oak and the jay is cemented when one recognises that both benefit very well from the association. As remarked above, the oak is able to regenerate in ideal conditions, though as the jay selects only the healthiest and larger acorns there’s also a direct filter placed upon acorn populations, that ensures only the strongest acorns ever have a good chance of germinating. Furthermore, the wide dispersal of acorns by the jay ensures that oak populations can spread quite markedly, with small satellite groves emerging at sometimes great distances from the parent tree. On the side of the jay, the provisioning of an important food source is critical, as without acorns the jay, in Europe, may have to find other significant sources of food with good nutritional value. Of course, it is also important that the right conditions are available for the jay – this means open areas of grassland, or mantle and fringe vegetation. Closed forests are not suitable for the jay, and it will thus not bury its acorns there. In fact, even though forest stands of oak produce 10-times more acorns than sparsely-populated open-grown oak pasture landscapes, the density of acorns within the soil buried by jays is 50-times greater within the open landscapes. Such landscapes are generated by grazing, according to Vera, and whilst modern grazing has been created by man (up until the decline on grazing, in recent times), historically the wild boar (Sus scrofa) would have provided good conditions (due to its disturbance of the soil in grasslands, which were created by large roaming herbivores – the auroch, deer, and wild horse, for example) for where the jay could bury its acorn collection.

 

Source: Vera, F. (2000) Grazing Ecology and Forest History. UK: CABI Publishing.

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04/05/16. Fact #197.

 

Currently, I am on chapter 6 of Vera’s book Grazing Ecology and Forest History, and there’s a great sub-chapter (6.2.2) that explores the relationship between the Eurasian jay (Garrulus glandarius) and the oak. I learned a lot from reading this specific segment of the book, and thus hope that others also find the following information useful.

 

Firstly, one can certainly recognise that oak trees in Europe (Quercus petraea and Quercus robur) do not generally regenerate in woodland. Whilst acorns do germinate, after a period of usually less than a decade, they cease to be, as they are out-competed by shade-tolerant species, such as hornbeam (Carpinus betulus) and beech (Fagus sylvatica). Instead, oaks oft regenerate amongst thorny scrub (in grasslands, grazed areas, and within mantle and fringe vegetation bordering woodland), be the scrub comprised of hawthorn (Crataegus spp.), blackthorn (Prunus spinosa), holly (Ilex aquifolium), gorse (Ulex europaeus), or otherwise. In many an instance, one can perhaps wonder how the young oaks reached and regenerated within such scrub, and most notably so if there are no sizeable oaks within the immediate area. One explanation for this is, as explained by Vera, and courtesy of an array of sources, the Eurasian jay.

 

As an oak releases its fruit crop (acorns) into the harsh environment during September to November, the jay will collect many of the acorns (the healthy, ripe, good-sized ones, generally-speaking), and bury them at a distance from the tree that may vary from tens of metres to a few miles. When a jay collects only one or two acorns, it may bury them only a short distance from the point at which it gathered them from, but if the jay carries five or six acorns (in its gullet, throat, and beak – the largest being in its beak), then the acorns may be buried thousands of metres away. All of the acorns collected in one ‘trip’ will be buried in close proximity to one another, at a maximum spacing distance of around 15m (usually 0.5-2m spacings). At the level of a single jay, this dispersal of acorns may be relatively small, but when amplified to a group of jays 65 strong, research has indicated that (over the course of four weeks) up to 500,000 acorns may be dispersed. This dispersal is also very significant at distances from nearby oaks, with approximately 5,000 acorns per hectare when the nearest fruit-producing oak is around 200m away.

 

eurasian-jay-acorn-quercus.jpg?w=660&h=440

A Eurasian jay with an acorn within its beak. Source: Phil Winter.

 

Jays also have a strong preference of burying their acorns in open areas with loose soil. Usually, this will be open areas outside of forests within grasslands and amongst thorny scrub (this explains why oaks may pop up amongst thick scrub), though if substantial forest clearings manifest (due to tree mortality – normally courtesy of windthrow and the forest edge effect), then they too may be alluring sites in which the jay may cache its treasure. Interestingly, open areas complete with loose soil and areas of thick scrub are akin to medieval wood pastures, where grazing would have occurred.

 

oak-regeneration-mantle-and-fringe.jpg?w=660&h=880

This young oak is growing amongst bramble and gorse, within a heathland area, and beyond the direct reach

of a parent oak (meaning the acorn didn’t just fall into this spot). Thus, it is likely that it was buried by a jay.

 

Once the acorn has been buried by the jay, it will cover the site with soil and leaves, in order to hide it from sight. In order to re-find it, the jay will remember the vertical structures of vegetation in the immediate area – their memory of where they have planted acorns is, in fact, very good. Interestingly, a jay will only be able to find acorns it has buried – it will not be able to locate acorns buried by other jays, unless that other jay is also present at the time of digging up the acorn. Typically, the acorns they bury will be eaten throughout the year, though the months of April through to August mark the period when fewest acorns are dug up and eaten. This drop in predation by the jay fits in well with the period of acorn germination, with the stem emerging during May and the first few leaves unfolding in June.

 

This development of the small leaf crown co-incides with when jays will begin to search for acorns with a little more intent, as it is during this time that they will be feeding and training their young to fend for themselves. When a seedling (that is still green in the stem, and thus not lignified) is found from an acorn that the parent jay had buried, it will pull it up and eat the acorn, before depositing the little seedlng back into the ground rather crudely. Its young will, actually rather hilariously, mirror this behaviour, though with far less finesse, and pull up not only oak seedlings but anything else they find as well. This removal of the acorn does however not have a huge impact upon the oak seedling, as the strong and extensive tap root developed rapidly after germination means that the little oak seedling is securely anchored into the ground and can fend for itself, even if the acorn (provides energy for seedling growth) is lacking. Essentially, the uprooting is a trade-off that the oak tolerates well, so to be able to grow in the full sunlight conditions the jay opts to bury its acorns in (and where they will grow best, as the oak is not shade tolerant). Research has even shown that many oaks bear the scar of early uprooting by a jay, though since that time they have developed into healthy young trees. Importantly, this disturbance event only happens once (usually), as jays will only uproot small seedling that they buried. Jays are very ‘untrusting’ of ‘foreign’ or ‘alien’ acorns and oak seedlings, and thus will avoid them, by-and-large.

 

The symbiotic nature of the relationship between the oak and the jay is cemented when one recognises that both benefit very well from the association. As remarked above, the oak is able to regenerate in ideal conditions, though as the jay selects only the healthiest and larger acorns there’s also a direct filter placed upon acorn populations, that ensures only the strongest acorns ever have a good chance of germinating. Furthermore, the wide dispersal of acorns by the jay ensures that oak populations can spread quite markedly, with small satellite groves emerging at sometimes great distances from the parent tree. On the side of the jay, the provisioning of an important food source is critical, as without acorns the jay, in Europe, may have to find other significant sources of food with good nutritional value. Of course, it is also important that the right conditions are available for the jay – this means open areas of grassland, or mantle and fringe vegetation. Closed forests are not suitable for the jay, and it will thus not bury its acorns there. In fact, even though forest stands of oak produce 10-times more acorns than sparsely-populated open-grown oak pasture landscapes, the density of acorns within the soil buried by jays is 50-times greater within the open landscapes. Such landscapes are generated by grazing, according to Vera, and whilst modern grazing has been created by man (up until the decline on grazing, in recent times), historically the wild boar (Sus scrofa) would have provided good conditions (due to its disturbance of the soil in grasslands, which were created by large roaming herbivores – the auroch, deer, and wild horse, for example) for where the jay could bury its acorn collection.

 

Source: Vera, F. (2000) Grazing Ecology and Forest History. UK: CABI Publishing.

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28/04/16. Fact #195.

 

This is from one of my assignments, so it's not extensive, but instead a sort of overview. If bits sound good, go and explore them. :)

 

For damages to be granted as a result of light occlusion to a property, it must first be established that there is indeed a right to light. Unless there is an explicit grant detailing a right to light, which is rare, right can come only in the form of prescription. Detailed in the Prescription Act 1832, a right to light may be acquired when a land owner has enjoyed uninterrupted light availability into his or her property for a period of at least 20 years. However, as the Act relates only to a specified opening (such as a window), the right to light can only be ascertained if it relates to a building; as confirmed in Harris v De Pinna [1886] and Levet v Gas Light & Coke [1919]. However, a building can also relate to a greenhouse, as stated in Allen v Greenwood [1980]. For example, if a new building is constructed that then limits the amount of light coming in through a window, and the level of light inside falls below the ‘accepted’ level, then this constitutes an obstruction. However, the accepted level of light ultimately relates to the intended use of the affected building, in turn making the accepted level of light non-constant. The more recent court case of Regan v Paul Properties Ltd [2006] even ruled that: “What matters is not so much the amount of light that is taken as the amount of light that is left as a result of the infringement. The consequence of the obstruction to the light in the middle of the living room was that Mr Regan would suffer a substantial interference with the enjoyment of natural light in his living room.” Whilst this related to the construction of a nearby building, such a ruling could potentially cross over to a ruling regarding light obscuration by trees. As of yet however, this has not happened, and it is therefore difficult to ascertain where the law stands beyond that of there not being an ‘active’ precedent. This is because trees only gradually increase in height, unlike buildings which are erected rather more swiftly.

 

The only existing law surrounding a right to light with regards to vegetation is the concept of a High Hedge, which is featured in Section 8 of The Anti-social Behaviour Act 2003. This involves at least a semi-evergreen hedge line of two or more specimens occluding light into a property (in England), thereby detracting from the enjoyment of the affected property. The threshold for whether a hedge is too high is determined by a series of mathematical equations. In Scotland, which has its own Act – The High Hedges (Scotland) Act 2013 – a high hedge may not be only from evergreen and semi-evergreen individuals, but deciduous broadleaved ones, too.

 

The Prescriptions Act does not apply to Scotland, and arguably there is no right to light or buildings up here. And although the Act is helpful in England, it did not create rights of light it merely clarified and shoprtened the prescriptive period.

 

There are many differences between the right to light at common law and the analsgus right to light over high hedges, but there are three essentially important ones. First the latter covers rights to light in gardens too. Secondly the latter doesn not cover non-residential buldings like workshops. Third the common law right is to perhaps as little as a fifth of the light levels tha the British Standard deems appropriate for adequate daylighting. The 'mathematical equations' are not really mathematical, they are derived form complex modelling of BS thresholds and then rounded very substantially upwards by political will. The guidance thus generated does not translate well to Scotland, as anyone that has noticed that our latitude is different will appreciate.

 

Your choice of words "a high hedge may not be only from evergreen and semi-evergreen individuals, but deciduous broadleaved ones, too." is a bit unfortunate, as I am embroiled in 2 appeals just now concerned with an almost exclusively Larch high hedge. And even in England I must point out that high hedges need only be predominantly evergreen or semi-evergreen they can be quite substantuially deciduous and still fall within the Act. Of course a thah piont the guidance, which is derived from equating their light-obstructing properties to those of buildings of the same shape, falls apart.

 

As I think would any common law case asserting a right to light through a tree. Perhaps that's part of the reason it's never come to court.

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The Prescriptions Act does not apply to Scotland, and arguably there is no right to light or buildings up here. And although the Act is helpful in England, it did not create rights of light it merely clarified and shoprtened the prescriptive period.

 

There are many differences between the right to light at common law and the analsgus right to light over high hedges, but there are three essentially important ones. First the latter covers rights to light in gardens too. Secondly the latter doesn not cover non-residential buldings like workshops. Third the common law right is to perhaps as little as a fifth of the light levels tha the British Standard deems appropriate for adequate daylighting. The 'mathematical equations' are not really mathematical, they are derived form complex modelling of BS thresholds and then rounded very substantially upwards by political will. The guidance thus generated does not translate well to Scotland, as anyone that has noticed that our latitude is different will appreciate.

 

Your choice of words "a high hedge may not be only from evergreen and semi-evergreen individuals, but deciduous broadleaved ones, too." is a bit unfortunate, as I am embroiled in 2 appeals just now concerned with an almost exclusively Larch high hedge. And even in England I must point out that high hedges need only be predominantly evergreen or semi-evergreen they can be quite substantuially deciduous and still fall within the Act. Of course a thah piont the guidance, which is derived from equating their light-obstructing properties to those of buildings of the same shape, falls apart.

 

As I think would any common law case asserting a right to light through a tree. Perhaps that's part of the reason it's never come to court.

 

A welcome addition to what I wrote, so thanks for that. Interesting on the larch appeals, and clarification on the nature of a hedge within England - i.e. deciduous specimens.

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06/05/16. Fact #198.

 

Within many urban environments, one can come across vacant parcels of land. Such land parcels may be in residential, commercial, or industrial areas, and oftentimes they will be home to, because of the lack of disturbance and management of the land, plants. Some of these plants will, of course, be trees (of varying ages – depends on how long the land has been vacant for). In certain cities, the amount of vacant land may be particularly high, with declining fortunes of landowners, a worsening economy, and a change in demographics, being three drivers of the abandonment of land. In Detroit, USA, for example, around 32% of all urban land is currently vacant.Of course, in many aspects, this is not good, though is there a silver lining to such vacant plots? The study investigated in this post (referenced at the bottom) seeks to establish just that, in terms of ascertaining how valuable vacant land plots are as green infrastructure.

 

The study area for the investigation was the city of Roanoke, Virginia, USA. This city was chosen as it has a wide variety of different vacant land parcels, of which many are old industrial (manufacturing / factory) plots that were abandoned as the economy declined and technologies changed. In total, the vacant areas of land were split into five different categories, as shown in the below table. Overall, 114 vacant plots, both under public and private ownership, were sampled.

 

vacant-land-types-city-tree.jpg?w=660&h=551

The five types of vacant land, as defined by the authors.

 

Of these land types, an area amounting to nearly 30% of the entire city was considered to be classed as vacant. Granted, some areas are intentionally vacant, as they are floodplains, wetland areas, and so on. The table shown below gives more of an indication of what land types there are in the city, and how much of the total city area they comprise.

 

vacant-land-area-tree.jpg?w=660&h=231

Total land area of the different vacant land types.

 

Within these vacant plots, there was a total of 210,000 trees (an average of 30.6% canopy cover, in these vacant areas); of which nearly 41% of the trees were quite small (below 15.2cm in diameter). The total number of trees are split as follows: (1) derelict: 25,725; (2) natural: 26,514; (3) post-industrial: 7,488; (4) transportation-related: 28.923, and; (5) unattended with vegetation: 121,613. Because of the species of trees found on the vacant sites (see below), it can be recognised that this data means many trees are young. This, in turn, means that the ecosystem services (filtering air pollutants, sequestering carbon, catching rainwater, cooling the urban environment, and so on) provided by the trees are rather limited, though as the authors note there is scope for the services to increase in time, as the trees mature. Of course, there are older trees within these vacant plots, and nearly 6% of all of the trees had a DBH of over 76.cm, though the population is heavily skewed in favour of young trees. It is also worth noting that the invasive tree of heaven (Ailanthus altissima) features rather readily, and this may be undesirable on an ecological level. In fact, invasive non-native plants are perhaps more likely to be able to colonise vacant land plots than native ones, in many instances – particularly on brownfield sites.

 

tree-species-vacant-land-urban.jpg?w=660&h=379

A breakdown of the tree species found within the vacant plots. The three main species are American elm (16.5%), tree of heaven (12.3%), and box elder (6.7%).

 

Combined, the trees within the vacant plots do however have many benefits. First and foremost, they have a very positive impact upon air quality, by filtering out harmful pollutants that, as a result, has a monetary value attributed to it (as shown below). For example, nearly 30 metric tons of moderately-sized particulate matter is removed by the vegetation every year, and this equates to financial benefits of $450,000 (nearly $16,000 per metric ton).

 

trees-pollution-removal-urban.jpg?w=660&h=540

The removal of pollutants by trees growing within vacant land parcels. The bars represent total pollution removal per year, whilst the triangles relate to the financial benefits.

 

Beyond the removal of air pollutants, the trees growing within vacant land also have a marked benefit when it comes to the sequestration of carbon. As carbon dioxide is considered by some (but not all) scientists as being a marked cause of climate change, some will promote the utilisation of trees for their assimilative capacity when it comes to storing carbon. In the study area, the 210,000 trees were found to sequester a gross total of 2,090 tons of carbon each year, which has a monetary value of $164,000. Granted, not all species are equal in this regard, and it is the American elm and the tree of heaven that top the charts for carbon sequestration (see the below graph), with the elm being far above anything else in this regard. Curiously, whilst the box elder is the third most common tree species within vacant plots, it does not rank third for carbon sequestration. When the authors looked at total carbon storage, which is what carbon has been stored over the trees’ lifetimes, a total of nearly 100,000 tons had been stored, which is valued at $7.6m. This value does however vary across vacant land types, with much of the carbon being stored in areas unattended that possess vegetation, though this may very likely be down to the fact that this land type has over half of the total 210,000 trees.

 

carbon-sequestration-trees-vacant-land.jpg?w=660&h=501

The total amount of caron sequestered, each year, by some of tree species found within vacant plots. Each metric ton of carbon sequestered is valued at $78.5.

 

These vacant land-borne trees also reduce the expenditure incurred by residents of the city, and particularly when it comes to heating or cooling of property. Each year, the trees reduced, by over $210,000, the expenses paid to heat and cool property. Such savings translate into indirect benefits for limiting air pollution, as this reduces cost is associated with reduced energy bills. This obviously means less energy was used, which implies that individuals emit (via consumption) fewer total pollutants, each year.

 

There also exists a structural value to the vegetation within these vacant plots, and for the city’s trees this amounts to $169m. Again, it is the unattended land that possesses vegetation that bears most of this value ($111m), as such land has by far the most trees, though other land types also have important financial values. The below table details exactly this.

 

structural-value-vacant-land-tree.jpg?w=660&h=272

The structural value of the trees within each land type, compared with the number of trees and the total cover of trees within each land type.

 

What I find particularly interesting about this study is that it suggests that we need to adopt a broader approach to how we view vacant areas of alnd within the city. Often, people will refer to areas of abandoned land within industrial and residential areas as wastelands, though according to this research they are anything but. Even though post-industrial and derelict land types themselves feature only to a small degree within the urban environment, they can certainly support tree populations, and the longer these areas remain void the better, from an environmental standpoint. Granted, there is a pursuit to re-build the economy after the banks managed to royally muck it all up and run off with billions in bailouts from the taxpayer, so such sites may be ear-marked for development if there is the justification, though at the same time there is huge opportunity to almost re-wild inner-city areas. Can there be a balance between the economy and the environment, therefore? If these sites are developed, perhaps there exists scope to retain some areas of trees. It’s also important to recognise the value these trees have by merely existing, and whilst it’s not a value that can be ‘cashed in’, it is nonetheless a value that should be properly recognised.

 

Source: Kim, G., Miller, P., & Nowak, D. (2015) Assessing urban vacant land ecosystem services: Urban vacant land as green infrastructure in the City of Roanoke, Virginia. Urban Forestry & Urban Greening. 14 (3). p519-526.

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08/05/16. Fact #199.

 

Man has always had a direct link to the landscape, though that link, whilst it is always there, may not be in the form that it once was. Keeping with the wood pasture theme, which I am really enjoying learning about through books and journal articles, I thought we’d look at how the manner in which we approach the ecosystem has changed over the centuries (quite briefly). Of course, what is written below doesn’t stop just at wood pasture – it has cross-over to other ecosystems, where the reasons for interaction with the landscape have altered through space and, more pertinently, time.

 

Historically, wood pastures were managed for economic purposes. The grazing of animals on grasslands containing trees (and the feeding of the livestock with cuttings from pollarded trees, and a tree’s fruit crop), such as cattle and pigs, was for the direct benefit of communities, who relied upon the produce of the livestock (milk, meat, and so on) in order to make a living, and to generally therefore survive. Of course, the wood pastures needed to be conserved, so that they did not disappear, due to over-grazing. In this sense, they were actively conserved (by replanting dying and dead trees, and limiting grazing intensity), though largely because, without actively conserving them, the livelihood of many tens of thousands of people would be challenged. A by-product of this conservation of wood pastures, for the benefits created from grazing livestock, was that the sites were very rich in biodiversity – birds, fungi, insects, and plants, for example. The complex mosaic of niches within the wood pasture, ranging from open and disturbed soils through to the (perhaps sizeable) groves surrounded by the mantle and fringe vegetation, meant that a large number of organisms could viably frequent the site. However, for all of the biodiversity present as a result of the careful management and conservation of wood pastures throughout history, biodiversity was not the reason for management – until recently.

 

The shift, in Europe, probably begun when wood pasture became disliked (for hope of a better word), during the 19th-20th century (varies depending upon the country). Foresters wanted to maximise output from the trees (coppice – sometimes with standards), and farmers wanted to maximise agricultural output. Therefore, the two practices, initially married, were divorced from one another (somtimes farmers were forced to stop grazing their livestock in wood pasture!). Wood pastures were thus either cleared of trees entirely, or alowed to regenerate into forest. With this came a decline in the richness of biodiversity and, eventually, this loss of biodiversity caused a rather evident of panic amongst conservationists. Ironically, therefore, the rationale behind creating and maintaining wood pasture became largely ecologically-driven, in place of economically-driven (though, particularly in Spain and Romania, wood pastures remain, are these are generally economically viable). Regardless of reason however, the status of wood pastures essentially went full-circle.

 

wood-pasture-estonia.jpg?w=660&h=440

A fantastic wood pasture in Estonia. Source: Ideas for Sustainability.

 

Of course, this new found love for wood pastures does not necessarily mean that they can ever exist in the manner in which they did before. First and foremost, wood pastures are extensively grazed, and thus, for operations to be self-supporting financially, they must cover large expanses of land (unless the wood pasture is maintained for subsistence purposes, or grants are provided as a means of financial support). As farmers in Europe are generally in ‘the game’ for profit (they must make a living), managing livestock in wood pastures is probably not going to be all too popular, as it’d probably signal a marked drop in profits and / or a marked increase in labour input (at least, initially). Scope does exist to harvest edible mycorrhizal mushrooms from the wood pasture, such as truffles, though this is a specialised pursuit that is far from the current farming status quo of Europe.

 

Furthermore, European culture has changed. Gone are the days of communities being self-sufficient, and instead many Europeans now work a job (that they may even hate) and buy their food from the supermarket (or even order it online). Therefore, is there even the desire to re-introduce wood pastures, for anything other than ecological reasons, or to supply the market with a niche animal product (such as Iberian ham from the black Iberian pig, in the holm oak dehesas of Spain). With this change in culture there has also been a change in learning priorities, and unfortunately many today seem to be fixated with knowing pointless facts about sports teams and celebrities. Functional and practical knowledge is largely gone. As a consequence, the management of wood pastures will be left to an expert few, where knowledge has either been gained academically, or via being passed-down through the generations (usually limited to rural areas where grazing still takes place). However, as more people now live in cities than in rural areas, and this trend will likely continue as rural areas are swallowed up by urban sprawl, or people move into cities for economic reasons, this tradition of passing practical knowledge on and keeping up the family tradition of extensive livestock grazing within wood pasture may very well become ever more the stuff of legend.

 

black-iberian-pig-dehesa.jpg?w=660&h=448

The black Iberian pig grazing amongst a landscape of holm oak, in a Spanish dehesa. Source: Andrew Petcher.

 

Society is simply in a different place than it once was. For this reason, the conservation of wood pasture is to be far from mainstream. People are certainly aware of nature (of which wood pastures feature), though more and more awareness comes from watching on the television and less from direct experience, and with this comes a discord. There is less emotional and cultural attachment to nature, and as a result, less of an impetus to associate with nature. Why help with the recreation of wood pasture when you can watch about its conservation on television, utter some lamentations, and then switch the channel and soon relegate it to a mere memory? That’s even assuming people watch such programs, in large numbers, in the first place.

 

This probably turned out far more dystopian than I ever intended for it to come out as, though hopefully this illustrates how social changes have led to landscape management changes, with specific focus upon wood pastures in Europe. This is obviously applicable to other landscape types as well, of course. The principle generally carries across.

 

Source (of inspiration): Hartel, T. & Plieninger, T. (2014) The social and ecological dimensions of wood-pastures. In Hartel, T. & Plieninger, T. (eds.) European wood-pastures in transition: A social-ecological approach. UK: Earthscan.

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Hahah maybe one day! Slowing down with them a bit as I'm trying to do so many things at once at the moment - read books, write these, explore landscapes, spend time with the missus, and writing other bits and bobs. Hopefully the length isn't too bad. I try to put pretty images in where I can, of course.

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