Cambridgeshire's chalk streams
Cambridgeshire's Chalk Streams: Burwell Brook
Burwell Brook rises near St Mary's church, in the field that contains Burwell Castle, in a series of crystal-clear chalk springs.
However what could be a pretty stream and a great amenity to the village is treated much like a ditch for most of its 1 mile length until it becomes Burwell Lode. Nevertheless the brook shows several distinct stages. Below the spring is a watercress bed: the watercress here flowers but appears to set no seed, so it is a Nasturtium x sterile, cross between the two types of watercress, Nasturtium officinale and Nasturtium microphyllum.
In autumn 2016 the brook was 'ditched' where it runs through farmland. This was unnecessary as it had been ditched a couple of years earlier and the vegetation was only just recovering. However this section of the stream was the site of an apparently large water vole colony which I have photographed. This ditch-work put paid to the water voles, which are a protected species. However the vegetation did not take very long to recover.
Click on a thumbnail for an enlarged view (with comments). Clicking on the enlarged view will download the full size original photo.
Burwell Brook's lower reaches
From the watercress bed to Priory Wood the brook flows quite fast through arable fields where the main water plants are watercress (Nasturtium officinale rather than Nasturtium x sterile which is present below the spring) and Fool's watercress (apium nodiflorum). But the brook slows and deepens where it runs adjacent to Priory wood and here Branched burr-reed (Sparganium erectum), Starwort (Calitriche sp.), Brooklime (Veronica beccabunga), Blue water-speedwell (Veronica anagallis-aquatica) and similar plants abound. There is however a lot of algal growth in this area - evidence of probable fertilizer run-off from the arable fields.
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Page first published Wednesday the 11th of January, 2017.
Last modified: August 21 2017 10:53:53.
Written by and © Richard Torrens
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