River Water Crowfoot (Ranunculus fluitans)

Dear Readers, most of the ‘weeds’ that I’ve been writing about during this past year have either been common, widespread ‘weeds’ or garden plants, but this week I want to tell you about a plant that is both unusual and very local. River water crowfoot (Ranunculus fluitans) is a member of the buttercup family that needs a clean, fast-flowing stream with a stony bed, where the water is both alkaline and relatively nutrient-rich, without being polluted by nitrates from run-off. I was delighted to find a fine crop of the plant in the tiny river that flows through Milborne St Andrew in Dorset. I wrote a bit about it in Saturday’s post, but thought that it needed a bit more attention. After all, it’s not every day that you encounter a relative rarity.

River water crowfoot can have stems that are up to 20 feet long, with each stem bearing several of the pure white flowers. The leaves are all thread-like and submerged, and undulate in the water in a very pleasing way. In the film below, I am holding the camera still and the water is moving. It’s maybe best avoided if you have a tendency to motion sickness.

MIlborne St Andrew has long been a ‘watery’ kind of place – a few years ago the village was cut off by flooding from this very same stream (which is a tributory of the delightfully named River Piddle). The area outside the shop was under about a metre of water, and this required a thirty-mile detour for anyone eager to get to or from the nearest railway station at Moreton. Some folk would disregard the warning that the area was too deep to ford, even in a Land Rover, and much entertainment was to be had by watching as the inevitable happened, and local tractors had to be summoned to get the culprits out of their self-inflicted immersion. Fortunately, a lot of work has been done and, fingers crossed, the stream is now relatively well-behaved, and whatever changes have been made seem to not to have affected the water crowfoot.

Incidentally, the name ‘Milborne’ gives you a clue – any place name with ‘borne’ in the name refers to a small river in Anglo Saxon. ‘Winterbourne/borne’, as in ‘Winterbourne Whitechurch’, means a stream that only runs in winter. In these days of flooding, it would be well to do a spot of research before moving to one of these delightful Dorset villages – those Anglo Saxons knew a lot about geography.

The presence of water crowfoot is thought by some ecologists to indicate the site of a collapsed bridge or old ford, though why I have not yet worked out.

Why ‘crowfoot’ though? The leaves of other species of crowfoot do have something of a bird’s foot look about them, but not here. Is it because it was thought that the seeds were spread by crows (not that unlikely, as many other plants arrive in ponds and rivers when birds stop to drink)? Or is it because crows were seen feeding in meadows (they love the insects that used to inhabit cow pats before the animals were regularly dosed with antibiotics)? The name goes back to the Middle English ‘crou-fot’, so it has been around as long as those Anglo-Saxon place names.

River water crowfoot is endemic to Western Europe, and the UK has over twenty percent of the total population of the plant. While it is classified as ‘Least Concern’ here, it is considered Vulnerable in Sweden and Near Threatened in Switzerland. As with all water plants, factors such as pollution and changes in river management can eradicate a population overnight. It was good to see the plants in Milborne in such abundance and obvious good health.

It is difficult to look at the streaming green tresses of the river water crowfoot and not think of Ophelia, and indeed Gertrude mentions ‘crow-flowers’ when describing the ‘fantastic garlands’ that Ophelia made before her suicide. Millais’s painting of Ophelia shows some river water crowfoot at the bottom of the picture, although when I look at this painting I can’t help but remember the terrible cold that the model, Elizabeth Liddal, caught while floating in a bath over a period of four months.

Ophelia by Sir John Everett Millais,(1851-2) (Photo One)

River water crowfoot is an important part of the ecosystem of a stream, partly because it provides cover and refuge for all manner of fish fry, insect larvae and other small invertebrates. Less obviously, dense stands of crowfoot can actually alter the dynamics of a stream, causing it to drop sediment in places where the plant forces the flow of the water to slow down. This sediment then enables other plants to root, and increases biodiversity. In particular, caddis and mayfly larvae are able to thrive, and these in turn feed the juvenile trout and salmon that may live in the river. It’s not for nothing that mayflies are the models for many of the lures used by fly fishermen and women. This fascinating article goes into greater detail on how the humble crowfoot can change the whole dynamic of a chalk stream.

Brown Trout (Salma trutta) – one of the fish that benefits from water crowfoot cover (Photo Two)

So, as I write this on a sunny, humid day, I turn to Edward Thomas, a poet who captured the English countryside in a way that is redolent of sunshine through trees and the song of birds, mixed with a deep melancholy. For those of you who might wonder what a sedge warbler sounds like (as I did), you can see and hear them at the link here.

Photo Credits

Photo One from http://www.tate.org.uk/art/work/N01506

Photo Two by Aaron Gustafson at https://www.flickr.com/photos/aarongustafson/4226641945