We were doing a woodland survey today, as a college thing (I'm a student at the mo). As I'm sure you will be aware if you live in the UK, there's been a bit of a cold snap this week.
We did three quadrants (or squares), each of 100 square metres (10m x 10m), with two 1m square patches randomly chosen in each. The larger quadrants were chosen not entirely randomly but more by where there were the fewest trees to get in the way. Then there was the actually quite simple way of measuring out a perfect square via trigonometry or something, which was made considerably more difficult by the aforementioned trees, which managed to get in the way all the same. Then there was the fact that no one quite remembered how to do it but, after few false starts, we got our quadrant marked.
At least once during the measuring and the recording, there was a brief hail storm. Not entirely unusual for southern England in April but, still, not especially welcome. As the second was being measured out and recorded, I was sampling the soil, which is basically a posh way of getting your hands covered in mud. You stick an auger in to take out a soil sample, ideally all the way into the soil and not onto a root a few cms below the surface. Then you look at it, think 'yup, that's soil all right' then get you test for 'soil type'. This involves damping it and then rolling it between your fingers into a ball and then a sausage shape and then into a crescent. There's basically a whole load of shapes and the shape that your soil fails to make defines what it is. In this case (and pretty much as I'd guessed before I'd even touched the stuff) it was sandy clay loam - sort of brick red and unable to roll into anything beyond a short sausage.
By the time we'd tested soil pH (5), the second quadrant had been surveyed and the occasional hail had now turned into actual snow. The third quadrant was set up in a manner of minutes in this sleety snow and then surveyed with equal vigour. 'Bluebell', 'tick', 'brambles', 'tick', 'celandine', 'tick'. 'Coverage?'...'Uhhhhhhhhhh... 26-33%?', 'yeah, pretty much'.
Then, clipboards, marker poles and all the other gubbins were gathered up and carried at a canter to a nearby café, with thunder rolling round the blackening skies above us. In the dry, we compiled notes and thawed our hands out.
I have always been a little sceptical of nature surveys, largely for the scenes described above. Many may well be conducted with full scientific rigour and by experienced and dedicated professionals. Others, however....
A 'soft science', I think they call it. Or maybe just the most objective way of measuring a very complex system that anyone has yet managed to come up with.
On the plus side, the sleet washed the mud off my hands so, you know, all's well that ends well.
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