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Plea for pleaching

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This is a bit of a departure for this blog. Generally speaking I tend to leave issues like landscape and gardening to the experts. In this weekend’s Vancouver Sun their gardening correspondent Steve Whysall has a longish piece about pleaching. As it happens, when we were in Paris recently we not only saw the results of pleaching, we also saw how it was done which means I have some photos – which had been on my hard drive and, until now, had not been posted to flickr. So, as with the piece about the Bombardier LRV mockup, I am going to try to do something in both channels.

Petit Trianon

Pleached trees at Versailles, Petit Trianon – my photo on flickr

Pleaching is a type of pruning on trees that produces a flat top and sides – essentially a box sort of shape. As Whysall remarks it’s “a classy way to give a street, courtyard, square, boulevard or avenue an elegant, formal look.” He wonders why it is not done more here, and I think the answer is simply that the traditions of gardening in France and England are different. The style most popular for the parks around the stately home were those fist adopted by Capability Brown. His style was to “perfect” a natural appearance and it almost completely replaced the formal patterns of gardens that preceded him. The formality of gardens in France, on the other had, tended to be preserved, although I was pleased to note that places like Versailles and Chantilly have English gardens in the Brown style.

English Garden Versailles

The English Garden at Versailles – my photo on flickr

The English Garden Chantilly

The English Garden at Chantilly – my photo on flickr

Whysall says “There is no denying it is a time-consuming exercise. It requires skilled workers and it is probably an expensive process.” This is based on his observations of some pleachers in Chartres. And he is probably right about what he saw there, as he is an expert at what he writes. The approach at the Luxembourg Gardens which I observed was rather different.

Pleached trees - Jardin du Luxembourg

Pleached trees – Jardin du Luxembourg – my photo on flickr

In the Luxembourg Gardens in Paris, for example, long avenues of giant chestnut trees have been pleached to create a superb formal, almost sculptural garden architecture with sufficient space underneath for people to sit, even have a picnic.

The Cutting Edge

Pleaching machine

But that is done with a truck mounted crane, on which the arm at the top has mounted a series of circular saws. This can be used vertically or horizontally – and looks very much like the large economy version of what happens to cedar hedges here all the time. The truck moves forward slowly and the top – or the side – of the tree is just taken off. This is quite unlike the selective pruning used for most trees to promote tree health and vigour. Rather it is a simple matter of keeping the spread of the canopy in check.

A suitable case for pleaching 1

A suitable case for pleaching 2

It is an approach which we would like to see applied more in Vancouver for very selfish reasons. If you have a north facing window on the top floor of a six storey building put up around 30 years ago, you will have noticed that your view of the North Shore Mountains is steadily decreased every year, as the trees, planted at around the same time the building went up, reach maturity.

There was the notorious case of the West End resident who was so annoyed by the loss of her view that she simply poisoned the trees responsible for it – even though they were city trees planted in the boulevard. She was convicted and fined, but the social opprobrium heaped upon her was so great that she felt forced to leave town. Some people – make that many people – feel deep affection for trees, all trees. And cannot bear to see them “damaged” in any way. Which, of course, lead to the great Stanley Park disaster, when large numbers of trees were lost in a windstorm and tree management policies were subsequently revised to be more pro-active.

Regimented trees

Place des Vosges, Paris – my photo on flickr


Place des Vosges, Paris – my photo on flickr

Update: July 28, 2012

This morning, on a short walk for a different purpose I saw something that reminded me I had intended to add to this post a while back. One of the nicest features of the west side of Vancouver are the narrow residential streets where the trees meet overhead, forming a green tunnel. I think that much of what Whysall wrote in his original Sun piece is quite simply wrong. Pleaching is not exactly highly skilled if you can do it with a large and rather brutal piece of machinery, and the result does not necessarily produce a better result – certainly not if you are looking for shade. The way these trees have been allowed to grow creates a more inviting, human space. So in terms of streetscape I do not want to see more pleaching. Yes, it would be nice if the sixth floor view was clearer – but living in cities means we have to learn to get along with other people. The lessons of history are that the people who planned cities who did not actually like people (Hausmann, Robert Moses, le Corbusier) did not produce spaces that worked well for everyone.

35th at Vine

34th at Vine

Vine at 34th

Written by Stephen Rees

July 8, 2012 at 2:48 pm

Posted in placemaking

Tagged with ,

8 Responses

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  1. Personally i like the ‘natural’ English look better.


    July 8, 2012 at 6:04 pm

  2. … the answer is simply that the traditions of gardening in France and England are different.

    Well, that has to rate as the understatement of the year! Hey Voony! Those french-men, they have a machine for everything! Non?

    My first time in Paris back in 1982 I was delighted to see the trees at the Tuileries “box cut” and still with little enough spring foliage that the pattern of cut branches was clearly visible. I was gobsmacked. I will add “pleaching” to “training” and “canopy” as the second of just two or three “tree words” in my vocabulary.

    I was told at about the same time that Vancouver arborists do maintenance on street trees on about a 7 year cycle.

    The most important urbanistic feature of a row of street trees, natural or pleached, is that when planted right they “define” the street space in much the same way as the streetwall of a row house, or a block of maisonettes.

    That’s important because as we widen streets to carry modern levels of traffic volume, we push the proportion of the street—its width to streetwall height ratio—outside the optimum limits for human sense perception.

    From on top of the Arc du Triomphe, for example, we can observe how double rows of trees, planted a good distance from the buildings themselves, correct for the street aspect ratio.

    The real treat at Versailles, of course, is the town that fronts the palace that was platted and built at the same time as the ‘great hunting lodge’. Back in the mid-1600s all that capability learned building gardens and moving mature trees was put to work to create what was then a ‘new’ urbanism. Versailles (the town) is said to have had running water and waste collection. Among its other perks was a new building type and a new street type.

    Contre Allées, local access side lanes separated from the centre lanes of the avenue or boulevard, are in evidence everywhere. What does the ‘separating’ you may ask? Trees planted in rows, sometimes pleached, standing in medians.

    These medians can act like islands of safety affording a place to wait for the break in the traffic stream, and cross safely to the tree median opposite. There are crosswalks in most corners, typically painted. But, really, it is possible to cross most streets safely when the Contre Allées provides the island of safety.

    We are now told that the combination of row of trees and Contre Allées are having positive results in enhancing the livability of buildings fronting arterials. That is really good news. Especially if you consider that the Tram/BRT/LRT could run on a Contre Allée, stop located in the median. We would be removing car trips from the poisoned arterials, as well as erecting effective screening to enhance the livability of place.

    Some people really like street trees planted in rows. I see them as essential elements in ‘good’ urbanism.

    I hold different sentiments for those occupying a sixth story of an apartment that are now having their view blocked by maturing tree canopies. (1) Hopefully they are the right kind of tree, and the leaves fall in the winter revealing the view, and letting in the solar energy. (2) If we solve the problem at level six, that still leaves at least levels 5, and 4 to worry about. (3) Learn to enjoy the luxury of shade.

    lewis n. villegas

    July 8, 2012 at 8:24 pm

  3. talking of french, having a machine for everything….

    Not long time ago, I was surprised by a wine maker from Okanagan, explaining he had discovered a wonderful machine in France:

    In Canada/US, we build our environment around the machine…in Europe, we build the machine to adapt to the environment…and obviously that apply to the urban one,…as well as pleaching, which is predating the machine pictured by Stephen.


    July 9, 2012 at 10:05 pm

  4. I am not so sure that there was such a huge difference between the French and English styles of gardening in the old days. Both the French and the English got their inspiration for buildings and gardens from the Italians during the Renaissance. The French first hand has several of their Queens were Italians.

    In addition French and English Kings and aristocrats were often related. Quite a few English aristocrats came from Normandy for example. The Duke of Harcourt family, for example, the oldest in France, has an English branch.
    The Plantagenet kings came from the Anjou (Loire Valley…where Henry II of England is buried).
    Louis XIV and Charles II were cousins. Their grandfather was Henri IV, who was Protestant and King of Navarre before he became King of France. He is the one who had Place des Vosges built, taking for inspiration the medieval new towns of the Southwest that all have arcades around their main square.

    French style gardens were, even in the days when that style was the most popular, not that numerous—considering the huge numbers of castles in France. Provincial aristocrats of a lower ranks weren’t likely able to afford the huge number of gardeners needed to maintain such gardens.

    I had about a dozen clients in the Dordogne that owned castles. Modest affairs, so to speak. Once the family home their were only used for vacations. All but one had gardens that were in a very disheveled English style…meaning that they grew as nature intended them to grow.

    My favorite client, whose 17th century castle looked like a farm on the front facade, told me that letting the garden go wild and having a few cows in a corner changed the property status to farm, lowering the property taxes a lot. He–mayor of the village and also a senator, like his father and grandfather before him– was the one who, in the late 60s, finally decided to finish the new wing of the castle. The family started building it in 1789 then never got around to finish it…

    Red frog

    July 10, 2012 at 9:32 am

  5. Some gardens in the Dordogne: click on English then on the main photo the history of the castle in the 20th century is both inspiring and sad
    the gardens are on the slopes of a U shaped hill with a great view of the Dordogne river from the top, where the several houses of the family, along with the house of the staff, are

    This garden was owned by one of our clients He and his wife were from English families and spoke the most refined French I have ever heard. They were very strict and demanding but genuinely full of praise when they liked the work we did.
    Their Dordogne property was only one of several they owned…funny enough they had rather let me drive them in my small Fiat when they came down for a short visit–by private plane–than pay for a taxi for a 30 km drive.

    Red frog

    July 10, 2012 at 9:59 am

  6. In Canada/US, we build our environment around the machine…[on the continent], we build the machine to adapt to the environment…


    I’m not trying to re-ignite the Hundred Year’s War, but I do see a difference between Great Britain and the French-Italian axis Red Frog alludes to. If I had more language skills, I would be able to add with more confidence an observation or two about the third leg in the stool—Germany.

    What I am going to focus on here is the use of street trees. They are missing from my image of the English town just as much as they are absent from the Italian Renaissance town (and Roma). In these places the parks are green, but the streets are not.

    But all this changes at Versailles. The tree allées are as much a part of the hunting grounds behind the palace as they are in the main avenues of the New Town that fronts the palace. Fast forward 200 years and the Haussmann-Napoleon III ouvre seems impossible without either the parks, or the tree-lined avenues.

    That exposes my joke about French machines. It was nothing more than the parroting back of a dumb line I heard once. Although when I delve into the background of 19th century engineers in the UK, I find that many of them are trained in France.

    Both the French and the English got their inspiration for buildings and gardens from the Italians during the Renaissance. The French first hand had several of their Queens were Italians.

    Red Frog

    Catherine de Medicis (Queen of Henri II 1547 – 1559) and Marie de Medicis (2nd wife of Henri IV, and Queen Regent for Louis XIII after the death of Henri—in which she is implicated).

    Ah… les femme fatales Italien. Marie built the Luxembourg Palace that Stephen shows us.

    The ‘huge’ difference it that Indigo Jones was in Italy, visited Palladio’s studio after the master’s death, and returned home with a copy of the Quatri Libri which survives today with annotations in the margins. Otherwise, the British sought to ‘improve’ on the formulae publishing a copy of Alberti with alterations, and more famously Vitruvius Britannicus.

    I am not trying to discredit one tradition in favour of another. I am a great student of the Georgian urbanism, I love Bath, the West End, Edinburg and Dublin as much as many other “continental” centres. However, there is the matter of latitude and solar angle that necessarily introduces constraints ahead of politics and economics.

    Vive la difference!

    The cultural intercourse between France and Italy, which after all share a border, is much more pronounced than between Italy and either Holland or the UK. The Venetian fleet which brings the Black Death to the sea ports of the Mediterranean, then sails up the western coast of France, and the Channel to enter London via the Tames, leaves an indelible record of infection and destruction that is also a marker for cultural exchange. There was direct contact. I just find that it is attenuated and regionally contextualized by the time it reaches (Germany), Holland, England, Ireland and Scotland.

    Thus, as Canadians, we have the luxury to look at both traditions with more or less the same eye. At least here—on the wrong side of the granite monolith of the Rockies, within our increasingly multi-cultural kaleidoscope that may finally put both American and British hegemony on a more even keel—we can look at both.

    When it comes to ‘good’ urbanism I feel myself the incorrigible cultural tourist or collector (to acknowledge my English roots). I will borrow, steal and learn from anything that purports to teach a lesson about what makes public space work for human sense perception and for supporting social mixing.

    But I am also deeply concerned about the collapse of society in my Latin American home and its neighbours. There is a joie de vivrein every culture if we look deep enough. However, there is no denying the deep shadow of our capacity for perpetrating man’s inhumanity to man.

    Ultimately, the machine that we are building in the most cross-cultural sense of all builds is democracy—equality before the law borne out of a deep seated sense of social justice. All the arts, including engineering, landscape, architecture, and urbanism reach their highest form of expression when they plumb the depths of the society of equals.

    I misread Stephen intention, thinking that ‘the understatement of the year’ was a comparison between our tradition of landscape in Canadian cities with either the French or the British traditions.

    Yet, there is something inspiring about those pictures of the French machines advancing slowly down a row of trees, pleaching as they go, shaping nature for human consumption.

    lewis n. villegas

    July 17, 2012 at 11:18 pm

  7. Hello, Stephen, I really enjoyed this piece. Perhaps you might be interested in a post I wrote about a hedge my grandfather pleached over sixty years ago in Derbyshire. I’m working on one right now called “How to Pleach,” which you can find by going back to my blog and entering this in the search area. Congratulations on such an extensive blog of your own! Best wishes, Virginia Smith

    Virginia A Smith

    October 24, 2012 at 9:19 am

  8. One thing is now clear to me from reading Virginia’s piece – what I saw going on in Paris wasn’t pleaching at all. It was simply tree shaping. There was no weaving of branches to make an impenetrable hedge. I had always thought the word for that was “layering” or simply “hedging”. And it is of course nearly a lost art in England as hedges have been ruthlessly ripped out in order to make mechanized farming easier – and making the English countryside look American! At one time it was possible to actually date a hedge by counting the number of varieties of tree in it – roughly one per century – and many dated back to long before “the enclosures” which stole the rights of the common from ordinary people.

    Stephen Rees

    October 24, 2012 at 10:03 am

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