Tree of the Week

Week 4 - Betula pendula; Silver Birch

In a series of seasonal tree idents, it had to turn up sooner or later. You all know this one, because whatever the season the white bark is prominent. Silver Birch is a pioneer species and pollution tolerant so suitable for industrial sites. Very tough and hardy but prefers light, dry soils. Catkins appear in early Spring and release clouds of pollen in April. Fairly short-lived, perhaps only 70 years.

Betula pendula

So, learn the Latin name (pendula means drooping and refers to the twigs) and then also consider the

following attractive birches;

Betula utilis var.Jacquemontii 

Betula nigra 'Heritage'

Betula pendula 'Dalecarlica'

Tree of the Week

Week 3 - Fraxinus excelsior; Ash

I’ve chosen Ash this week as its another dead easy winter identification. This is because of the leaf buds, which are positioned in opposite pairs along the twig. They are pointy, in a slightly angular cone shape, and quite prominent because of their coal-black colour which has no shine to it at all – just flat black. Some other trees have dark buds but none that you’d mistake for Ash. Easy to remember because of the link to burning – black – ash!  If buds are out of reach for some reason, take a look at the trunk – the bark is quite deeply ridged in a vertical pattern on a mature specimen and is a true grey. Younger trees have smooth bark.

The tallest UK native tree and a pioneer species, it is known for easily colonising brownfield sites. The seeds are spread on the wind in the form of keys. Seedlings spread and germinate easily in large numbers if they fall on clear soil.

Don’t confuse it with the Mountain Ash as they are very different in size and form. 

Also, here is a handy Natural History Museum site which gives you lists of plants native to any postcode.

What urban vegetation is for...number 7; a means of reducing human alienation from the urban environment

This one seems to me to be pretty uncontroversial. There are many ways in which alienation from urban surroundings manifests itself. It is evident in visible forms such as litter on the street and vandalism of buildings and street furniture, but also has internalised outcomes such as depression and substance abuse. It engenders that feeling familiar to most urban dwellers when they travel through a particularly deprived part of their city, or find themselves having to live or work there. It’s a shiver of revulsion down the spine. It is fear, or pity, or bad memories.

Remediation of industrial contaminated land is a cornerstone of landscape urbanism. It’s a goal and a principle. With some sites, though, physical remediation alone may not bring the place back to life. In such places, landscape architects perform a kind of social remediation. Without human input and interest, design projects will of course fail, and I propose that a very effective way of engaging that interest and demanding that input from a local population is through vegetation.

There are plenty of good examples of this working through urban wildlife habitats and outdoor health facilities. Another obvious case would be that of growing food as a life-affirming leisure activity which actively engages the growers with a place and through which no-go areas can be psychologically reclaimed by a body of people. Take as an example the old water treatment plant near where I live in South Manchester. At the moment it is an interesting spot, claimed by a small and specialist group of graffiti artists who update their installations on at least a weekly basis. I know this because I go and look at their art a lot, but there are many people who certainly would not go and look – wouldn’t go near the place, in fact, because of its ‘edgy’ feel.  It could be reclaimed for the whole community, however, with a little creative demolition and a few raised veg beds...an LU allotment site which could provide a focus for further regeneration without necessarily evicting the artists, who could perhaps come along and plant some tomatoes in this little walled suntrap when they come to repaint their stretch of wall.

                              

                           

Tree of the Week

Week 2 – Aesculus hippocastanum; Horse Chestnut, conker tree

This week I’ve chosen a common street tree that is dead easy to identify all year round. At this time of year the obvious distinguishing feature is the leaf buds. They are the only buds you will find that are a big fat teardrop shape at the end of the twig, dark brown and very sticky, like a chewed toffee. Also, the leaf scars on the twig, where the previous season’s leaves have dropped off, look like tiny hoofprints running up the twig – hence its really easy to remember that this is the Horse Chestnut. ‘Hippo’ is Greek for horse – as in Hippopotamus, ‘horse of the river’. Trivia like this helps me to remember botanical names! It's a big tree, so if you can’t reach a twig, you’ll need to look for rough grey bark as shown below, and the form of the mature tree is domed, like the end of your thumb. Conkers germinate easily if they fall on good soil. You could grow one in a pot at home, but then you’d end up with an unwanted conker tree. In early summer the flowers look like candles standing up on the branches all over the tree.

Once again, lots more interesting info about this tree at Kew’s site.

                                            

Tree of the Week

First in a new series – its Tree of the Week! Each week I will choose a tree that has seasonal interest of some kind and give just a few ways of identifying it.

Week 1 - Platanus x hispanica, the London Plane

Tree of the Week kicks off in style with a common street tree that has it all. This time of year it looks like the branches have been hung with thousands of baubles; these are the fruit which will release their seed in Spring. Silhouetted against the winter sky they make the canopy of the tree unmistakeable. The ‘camouflage gear’ bark marks this tree out all year round and helps it tolerate pollution by shedding the build up of particles as it flakes off in layers. A great city-dweller, it also puts up with drought and compacted soil. They grow to more than 30m, can exceed 200 years old and have been widely grown in this country since the 1600s. It sets fertile seed and can be pollarded.

For more detailed information, try Kew Gardens.

        

What is urban vegetation for?

Reading the excellent Topos  (no. 77) in the library today, I was struck by a comment from Jorg Sieweke in a piece called ‘Paradox City’. He claimed that “the promise of Landscape Urbanism has lost momentum and struggles with credibility ...people are overwhelmed by too much change and too few means of handling it”. This seemed to me an odd claim to make in a journal brimming with LU thinking, both in its theory-based features and its write-ups of built projects. Immediately following Sieweke’s article, for example, were some very clear-thinking polemical pieces by Leibniz University’s Antje Stokman. She writes with simple purpose and legibility about LU thought and practice, for instance stating “one can never control landscape because it is a process.” She has prompted me to synthesise some thoughts about planting within an LU context, so here is my own list of some things that such urban vegetation might achieve, if done well;

1.       It is allowed to grow and change in unplanned ways which are steered by the designer

2.       It has a constructive interplay with human systems

3.       It is the backbone of a place rather than merely an adornment; it drives the process of city formation

4.       It has the potential to be the basis for new natures

5.       Its beauty is in pragmatic function not visual aesthetic

6.       It resolves conflict between design and ecology

7.       Its a means of reducing  human alienation from the urban environment

8.       It has concord with the identity of the place and is located in its biotic context

9.       It defies accepted divisions between the urban and the natural

10.   Is sustainable

11.   It aids social and physical reclamation of spaces

12.   It sows the seeds of future possibility at all scales

13.   Has final forms open to speculation

Hmm, thats quite a few. I propose to reassess these, one by one and in no particular order, in future blogs. I will probably get rid of some of them and edit others. Some might turn out to be laughable. But in the spirit of discovery and genuine enquiry, let the thought experiments begin!