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Photos from a walk on Thursday January 30th from Ewelme to Swyncombe


Three out of five January walks have been sunny.  Not bad, and today was lovely, if a little chilly when walking through the woods in the shade.

 

Coming out of Ewelme we followed an ancient path, probably created by folk returning after an evening in the pub. The lane running parallel is called Firebrass Hill. No idea why.

 

Further on, an unusual aligment of Brightwell Barrow, Didcot Power Station chimneys, and Wittenham Clumps.

 

While, a bit further on, we could see Jet (just) and Britwell Salome House

 

Often we walk to Swyncombe along Swyncombe Downs, following the path along the crest of the hill.

 

Beside the Ridgeway path up to Church Lane is a mature hedge, which was layered five years ago

 

Here’s how it looked in February 2020

 

Leaving the church, I noticed this “sticking out bit”. Need to go back to find out what it is.

 

Splendid tree silhouette while going down the hill from Ewelme Park

 

The path opened up

 

And closed again along Grindon Lane

 


Not may bugs or flowers (snowdrops excepted) about still, so here’s some lichen, taken at the coffee stop. Golden Shield Lichen (Xanthoria parietina)

 

And Dotted Ribbon Lichen (Ramalina fastigiata), looking as if it’s moulded out of marble

 

Lichens are truly fabulous. Also there isn’t much colour around at the moment so this Golden Shield Lichen provides a welcome exception.

 

The first thing to know about lichens is that they are not one organism but two. A lichen is partly a fungus – but the fungus can’t photosynthesise (ie it can’t turn sunlight into sugar) so it needs help. It gets that help by providing a home for a green algae which does the photosynthesis on its behalf. Together the fungi and the algae make up the lichen.

 

The algae of our Golden Shield Lichen is called Trebouxia. Trebouxia can also exist by itself – it just doesn’t thrive quite so well without its fungal chum. It also gets everywhere and is found in both polar regions as well as in fresh and salt water and in the desert. …

 

The second thing to know about lichens is that many are sensitive to air pollution and are used by researchers to help measure air quality. As a rule of thumb, the smaller and less variety of lichens in an area, the more polluted is the environment. …

 

The third thing to know about lichens is that they are are old. Like REALLY old. Humans emerged in Africa about 2 million years ago. Lichens have been here for at least 45 million years, one of the very first organisms to colonise dry land. [source]

 

Dotted Ribbon Lichen Ramalina fastigiata is also sensitive to air pollution and has been used in several studies as a biomonitor of atmospheric pollution


7 replies on “Photos from a walk on Thursday January 30th from Ewelme to Swyncombe”

Thanks David. I really like the photographs of the lichens and the accompanying description. Vast landscapes in those other pics – we look like midgets.

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