I see the purple flowers of butterfly bushes growing out of the brick railway arches on the approach to Manchester Oxford Road Station.
While attempting to understand more deeply the plants and seasons of woodland takes up a lot of my inner time as of late (hence the blog), another instance of ecology has interested me since long before I knew what ecology was (not a very long time ago): the way natural processes reclaim and shape urbanized space, or, the way urban space returns to a wild ecosystem. How animals, plants and fungi return to an abandoned urban site after their intentional eradication is an area of ecology that is difficult to study at length, mainly because there are very few urban sites that stay abandoned for long. In research terms, one of these ‘pioneer ecosystems’ attaining an age of more than six years is often a rare occurrence. The land in which the ecosystem has begun to develop is once more sold, occupied, and usually built upon, the final process almost invariably erasing any trace of the fledgling natural community. This has not stopped those interested from noting the swiftness of well-known pioneers: the sow thistle (Sonchus spp.) many of the mustards (Brassica spp.), viper’s bugloss (Echium vulgare), common mullein (Verbascum thaspus), yarrow (Achillea millefolium), the burdock (Arctium spp.) the butterfly bush (Buddleja davidii), the birch (Betula spp.), the poplar (Populus spp.), and the false acacia or black locust (Robinia pseudoacacia) to name a handful, from small annuals through to tall-growing deciduous trees. But what if this process of natural reclamation could be observed after a sustained period of, say, several decades?
At Berlin’s Naturpark Schöneberger Südgelände, one has the chance to witness just that; a diverse returning ecosystem thriving amid the sleepers, rails, and rusting machinery of a derelict train depot. Built in 1899, the Südgelände served as a switch-yard until after the end of the Second World War, finally closing operations is 1952. The GDR contested the validity of de facto West-German ownership of the site, and the resulting stalemate helped to keep the 18 hectare switch-yard almost completely sealed off from the outside world until the early 1980s, when plans for a modern freight station on the existing route were opposed by the scientific community and the public, due to its unique ecological and cultural fate. The site commission received official status and funding to maintain the facility as a nature reserve, opening in 2000.
Having experienced a state of almost uninterrupted rejuvenation since the middle of the last century, the rail sidings of the Südgelände have become a place of abundant and diverse natural forms. A great expanse of the depot being essentially an open, humus-poor field, you find swathes of evening primrose and grass lilies, sedges, spurge; the returning staples of a healthy dry grassland. You notice sudden and isolated appearances – the coastal everlasting (Helichrysum arenarium) in summer; lonely stands of sea buckthorn (Hippophae rhamnoides) later on in the year.
The Berlin-Dresden rail connection was completed in 1875, and, in the ecological sense, the growing overland network acted as a corridor by which foreign plants and animals reached the waste land of Berlin. Just some of the plants spread through mainland Europe since the advent of the railways are: purple herb robert (Geranium robertianum subsp. purpureum), the prickly Russian thistle (Salsola kali subsp. tragus), rue-leaved saxifrage (Saxifraga tridactylites), and Virginia pepperweed (Lepidium virginicum). Two more familiar examples are pineappleweed (Matricaria discoidea) and annual wall-rocket (Diplotaxis muralis), and the ragworts (Senecio spp.) (Dietmar Brandes, TU Braunschweig 2005).
The daily flow of material and goods through the depot and its subsequent isolation from city development has inadvertently created a niche for a whole host of European flora and fauna – it’s easy to imagine seed dispersal (not to mention insect larvae and eggs) in the packing material of and underneath wooden crates, in mud caked to the trains’ fenders… The Rangierbahnhof site supports (at the last count) 366 species of plants, 49 of fungi, 28 species of birds, and an enormous 208 species of wild bees and wasps (Kowarik & Langer 2005).
It would be interesting to know how drastically this abundance would compare with that of the railway sidings of next functioning station to the south (Südende). That’s the first of many questions; what number of these species are found solely on the site? To what extent did the closing of the depot secure a niche for new species? It is tempting to use the word unique in describing the atmosphere and history of the place, but would it be far-fetched to think that these wild time-capsules are more common than previously imagined? More about this unusual wilderness (and others, if they’re to be found) coming soon.