US social scientist Kenneth Boulding : ‘If you believe exponential growth can go on in a finite world, you are either a madman or an economist’.

Thursday, 7 October 2010

7/10/10: Crayford Creek exotics and missing Marsh plant

The land-filled 'landward' end of Crayford Marshes, along Crayford Creek, has long been known for its 'exotics'. There are a number of such records in Rodney Burton's 'Flora of the London Area' (published by the London Natural History Society in 1983).

A few more were gleaned today. On a bund of clay-ey spoil by the 'entrance' to the marsh (TQ 53026 75581), were the following garden escapes, all in flower ........

Ice Plant (Sedum spectabile)

and a red-flowered single Dahlia (foreground) with two substantial yellow-flowered Marvel of Peru (Mirabilis jalapa) behind, left.

My actual 'mission' was to search for any remnant of the very rare Marsh Sow-thistle (Sonchus palustris), for which the bank of the Creek was a well-known site. Indeed Burton says that there used to be a 20 yard strip of it. Armed with a grid reference provided by someone who had recorded it there in the past, I checked some tens of metres along the bank either side of the stated location. As thoroughly as I thought prudent, at any rate - given that this involved 'wading' up to my thighs in flattened Phragmites, and a blanket of Cow Parsley, Nettles and decaying Hedge Bindweed, such that I could not see where my feet were going and I was concerned I might disappear down into some hidden, wet and deep ditch. But there was no sign of the Sow-thistle which, it has been alleged, was deliberately destroyed by persons with development proposals in mind.

Former Marsh Sow-thistle site, now a mat of Common Reed and coarse 'weeds'

Mayweeds and Bristly Ox-tongue brighten up landfill capping on Crayford Marshes

Looking across Dartford Creek (the River Darent) towards the flood control barrier near the Thames, showing the flat, open character of the marshes. The low rise on the horizon, in the centre of the picture, is part of Essex, on the north bank.

Further on, the was a small patch of Tansy in the footpath, and a larger one not far from the fence in a neighbouring field. A Little Egret took flight from the Dartford Creek.

Along Moat Lane several Geranium pyrenaicum, Common Toadflax, Spotted Medick and a single White Melilot were seen. There were two Mute Swans on Howbury Grange moat.

Towards dusk now, around 80 Starlings were wheeling over Slade Green station.

No comments:

Post a Comment