All you need to know about water crowfoot, including where it grows and how to identify it <\/p>
The blooms of water-crowfoot, a helpful aquatic plant, brighten streams and rivers in early summer<\/strong><\/p> Like blackthorn<\/a> blossom that has fallen into a clear stream, water-crowfoot brings a smile to the water. In May and June, the crystalline purity of England\u2019s chalk streams lights up with the five white petals of this aquatic member of the buttercup family, the display draping over the long ropey filaments of the submerged plant. <\/p> Far more than just a pretty sight, water-crowfoot is a barometer that allows us to gauge the health and cleanliness of the stream. The plant is also a surprising habitat that supports a rich collection of life, from freshwater shrimps to Atlantic salmon<\/a>. <\/p> Water-crowfoot has a family network as tangled as its stems. In Britain, many different species occur, which are difficult even for experts to distinguish. But regardless of which species is in a riverbed, water-crowfoot functions like fingers in the waterflow, sediment catching on its feathery fronds. As you look from the bank upon its long green strands, it is easy to imagine the nymphs and larvae sheltering there. <\/p> Fish soon follow. River-keepers have long tended water-crowfoot, but science provides a startling view of this plant from a salmon or trout\u2019s perspective. Research on the River Frome<\/a> in Dorset<\/a> shows that not only do young fish congregate around it \u2013 giving protection from predators and extreme temperatures \u2013 but they grow faster and better, increasing their chances of survival when they migrate to sea. <\/p> Like all buttercups, water-crowfoot has a sinister side; it contains a compound called ranunculin, which is poisonous to many mammals if eaten. Nevertheless, water-crowfoot is foraged by swans<\/a> and ducks<\/a>, which has caused concern on occasion when grazing pressure is severe. Low water levels from abstraction are also a risk to the plant, as is nutrient enrichment. When inputs such as phosphates are washed off farmland or leak from sewage effluent, water-crowfoot tends to decline and algae blooms instead. <\/p> Water-crowfoot is by no means limited to chalk streams \u2013 its pretty white flowers adorn many larger and slower watercourses. But the chalk remains its most poetic home. These chalk streams are one of our special habitats; England hosts over three quarters of the world\u2019s total. <\/p> Listen to our award-winning podocast, The Plodcast, when we explored the amazing life of a Hampshire chalk stream with insect expert, Dr George McGavin.<\/p>How to identify water-crowfoot<\/h2>
Why is water-crowfoot a sign of a healthy river?<\/h2>
Is water-crowfoot under threat?<\/h2>
Where to see water-crowfoot<\/h2>