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sheep's sorrel

Erosion Gully

Monday 28th August 2000, West Yorkshire

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 Deadman's LaneTHE HEAVY RAIN turned Deadman's Lane, Thornhill, into an erosion gully. A walk up the rough track is like following a (dried up) river to from its mouth to its source. Here, on the path beneath your feet, are erosion and deposition features that you'd find associated with a full scale river.

My diagram greatly exaggerates the vertical scale, but that's what it sometimes feels like to ascend the lane on hot day! And, of course, there isn't really a cliff face at the side of the path, that's my artist's impression of the geological section.

Delta of Debris

When the torrent spread out across the road at the foot of the slope it dumped its load of sand, gravel, mud and twigs. The fan of debris is fairly chaotic, but there are traces of distributary channels, separated by sandbanks. Not quite the Mississippi delta then.

On the steeper middle section of the path-cum-torrent there's a scoured channel - a little river bed a few inches deep and about a foot wide. The stream has twisted on its course and, where it has come across an obstruction, such as a large stone, it has dumped debris such as twigs and leaves which are stacked up like a rack of toast, mainly at right angles to the current.

This reminds me of the fossil log jams and accumulations of dinosaur bones that have been found in some fossil river beds.

On this steep section the storm has washed clean the rough sandstone cobbles that line the bed of the lane. Some are so large that I suspect we are seeing the underlying bedrock. Other stretches look as if they have been roughly cobbled with a varying degree of skill.

Upper Reaches

At the top end of most river systems is section where the youthful stream can't do much more than re-sort its bed load. There isn't the power that's available to the mature river, lower down the slope. Eventually we step up to a flatter area where erosion is barely perceptible and the weeds get a foothold on the path/stream bed. These plateaux between river systems are sometimes called interfluves by geologists. The path at the top end is scattered with limestone chippings. I suspect a greater length of the path was originally covered, but the chippings on the steeper section have now been swept away.

The path climbs up the western slope of a valley that follows fault lines.

Haresfoot Clover

haresfoot clover Haresfoot Clover grows on the grassy trackside at the top of Millbank. It looks like a pinkish grass or plantain that has gone to seed, so it would be easy to overlook (unless, like me, you take an interest in grasses and plantains!). Although I don't remember having seen this plant before, the name Haresfoot Clover comes into my mind as I look at its furry flowers and its elongated version of the three-lobed clover leaf.

Later I realise why it is so familiar; I painted this species, also known as Rabbit's-foot Clover, Trifolium arvense about ten years ago for Wild Flowers of North America, published by Gallery Books, New York, and Dragon's World, London in 1990. It was written by Pamela Forey who, as I found out to my cost, was a terribly keen botanist. She wanted all the diagnostic details included in the illustrations. She'd have sent Monet's water lilies right back to him, saying he hadn't shown all the stamens.

The discipline of drawing several hundred botanical studies to Pamela's exacting requirements has meant that, to this day, I still look out for bracts, tendrils, stem grooves and plant hairs when I look at a wild flower, so I owe her a debt of gratitude, much as I might have grumbled at the time.

My clovers are on page 80/81 of the book, and I'm still pleased with them. Of course, if I did them again, and I didn't have a botanist to please, I'd do them differently, but for the brief I was given, they're not too bad. The artwork also appears in a European volume. And, by the way, Dragon's World were good enough to return the artwork, so if you're ever looking for a hundred small botanical studies to frame for your wall, please send me an e-mail. You know a set of three would look great over there in the corner by your computer . . . I'm afraid some of the clovers and orchids have already been sold. You're welcome to take a look at my Willow Island Gallery to see a small selection.

sheep's sorrel Haresfoot Clover is typical of grassy places and waste ground, and is often found alongside Sheep's Sorrel, Shepherds' Cress and Birdsfoot.

Related Links

Geology can stretch from the pebble that you pick up in your hand to a satellite image. It can reach back in time from yesterday's storm to a dinosaur's footprints. So, after looking at a local gully, here's the bigger picture; the United States Geological Survey.

And, on this side of the Atlantic check out the Earthwise publications (some of which I've written and illustrated), maps and regional guides published by our own British Geological Survey.

Richard Bell
Richard Bell,
wildlife illustrator
E-mail; 'richard@daelnet.co.uk'

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