Friday, March 02, 2007

It's Friday, it's not fibre

It must be time for a landscape. Remember the photo of the barrows on a snow-covered hill? This is the view from the top of one of those barrows. Click for bigger. We're standing on the Middle Chalk at about 95m OD (Ordnance Datum, which is mean sea level at a location I can't recall), looking across a vale averaging c. 30m OD of clays (Lower Chalk, and Gault) to a ridge you can just see in the distance. It might not look much like the English landscape of your imagination, but then this is what Oliver Rackham calls 'planned countryside'. People probably began farming here about 5,000 years ago and has been cultivated more or less intensively ever since. I was going to apologise for not erasing the by-pass and its railway bridge (I've already removed 2 cars and a van that offended me. Be afraid, be very afraid) but in fact it's a useful landmark being so... obvious.

That thin dark line running almost horizontally across the field just 'above' the bridge is the hedge marking a parish boundary roughly following the line of fields laid out in the Iron Age, c. 2,500 years ago (this is known from cropmarks showing the ladder-like outlines of the fields). The remains of what may have been the village in which the farmers lived survive as cropmarks near a spring about 1km west of the pale blur above the green field above the bridge, the pale blur being the modern village in which I live. This village probably took its present form in Saxon times (after the Romans left in 410AD); it's even been suggested that a single powerful individual planned the layout of the roads and farms within the village. There are other ways in which our modern landscape is defined by history and geology. Can you see the pattern of alignment of fields? One set of boundaries is the line of that hedge, running away from the main road (a northwest-southeast alignment), while the others parallel the road in the foreground running (very roughly) northeast-southwest. This last is the line of the Chalk itself, which has been a landmark and a high, dry route for travellers since people first arrived here after the last Ice Age, 10,000 or more years ago. The road in the foreground and other tracks paralleling it in the distance were used in summer by people travelling from spring to spring, perhaps driving livestock to market. The roads and tracks out of sight behind us, high on the Chalk, were winter routes used when the clays on lower ground became intractable mud.

Now it's Saturday. He came home last night in his car with rubber from a truck tire welded to the passenger-side door after being sideswiped on the motorway (aka highway) by a Spanish truck driver. Fortunately the vehicles were travelling at the same speed. No one hurt, but it could have been so much worse.

If you look closely you might be able to distinguish shades of green in the fields, as well as bare soil. The ploughed fields are waiting for summer crops such as sugar beet and field beans. The brown/tan/green are fields left fallow possibly until the autumn, or they may be ploughed soon for a spring crop. The darker green is oilseed rape ('canola' in NAmerica; the derivation of the European name is given in the link). The chlorotic green is autumn-sown 'winter' wheat desperate for a nitrogen fix, not surprising after a couple of thousand years of intensive farming! Until quite recently the nitrogen shortage wouldn't have been so obvious, as the farmers applied nitram (ammonium nitrate fertiliser) during the winter so it was 'ready' for spring growth. This is no longer allowed, because this area is a Nitrate-Vulnerable Zone. Aquifers in the Chalk provide our drinking water. Any winter rain flushed the nitrate through the soil into the water table, polluting the aquifers. A few years ago the nitrate content approached the EU permitted maximum and our local water company actually had to pump out the aquifer(!), pumping water from local boreholes out of the Chalk into tankers to be discharged into a local river (probably even higher in nitrates due to agricultural run-off) and hope that rain would recharge the aquifer in time for summer demand. I was... gobsmacked might be an appropriate phrase. Most of the settlements in this area take their water from the Chalk; as a result, most village wells dried and were filled in during the 1960s and 70s, and the springs that supplied the Iron Age villagers flow only in the wettest years. There are a few large springs that still flow today, but they must have been much more impressive before water abstraction began.

There are more trees in that landscape than have grown for perhaps the last thousand years or more. Before the 19th-century Enclosure of the parish, there were few trees or hedges in the open fields. Firewood to heat houses or cook meals was a valuable commodity; the laws determining who is allowed to collect dead wood where still stand on the statute books. As the open fields were enclosed* thousands of miles of hedging were planted to mark the new boundaries. Today mixed farming is almost unknown in this area; tractors don't need hedges to stop them wandering, so the hedges are often mismanaged or left to grow up into lines of small trees, while shelter belts and other trees have been planted to improve the view or the prospects of the hunt. The dark line on the top of that distant ridge marks the only 'real' woodlands in this area, trees that may originally have survived because the heavy glacial clay soil on the ridge was unploughable until tractors appeared. But, as the woodland elsewhere was cleared to become arable fields, these remaining woods became incredibly valuable sources of wood and timber. One of those dark blurs is an ancient wood, perhaps a remnant of the forest that once covered much (but not all) of lowland England.

As I write this, I am reminded that every landscape has a story to tell. It's just a matter of learning the languages – geology, history, natural history – in which the story is written. England has been settled for so long by curious people with leisure to learn that it's easy to find books telling the story. I particularly enjoyed Fortey's The Hidden Landscape and the book by Rackham I mentioned earlier. I'm not familiar with similar books for anywhere else, but John McPhee's Annals of the Former World, a mammoth introduction to the geology of the US, is one of my favourite books. Together with a set of US maps it lives in our bathroom within arm's reach of the loo. My favourite bathroom reading.

And now it's time for fibre. There's a spinning group meeting today about 30 minutes from here; I've been invited to drop by and see what 30-odd spinners look like. 'Terrifying' is perhaps too strong a word, but I am after all accustomed to doing all my fibre-things sitting in solitary splendour. I do want to investigate wheels, though... he didn't flinch noticeably when I mentioned this last week :-)

* a few, now famous, still survive. Soham in Cambridgeshire, for example.


HPNY Knits said...

nice photo- I like your long shadow. I will learn to spin next week! can't wait. the spinning group sounds great, too bad its too far, for me...
hope you had fun!

Joanne said...

Glad to hear the accident didn't result in any injuries..and interesting to hear about your detailed understanding of your local geological landscape. I'm not scientist enough to get excited about this sort of learning, but I try to absorb what others teach me. I hope the spinning group was fun?

sarah said...

It was better than fun. It was fun and learning and, and *everything*. I hope the shine doesn't wear off :-)