It wouldn't be an overstatement to say this is world-renowned as one of the best exposures of limestone pavement in the UK. Textbook stuff, quite literally.
I briefly explained the subsurface formation of the pavement's distinctive fissures (grikes) and blocks (clints) in April, but this photo shows the result of exposure of the rock to the open air: wind and, particularly, rain eat into the soluble limestone. Had the clints been exposed from the start, they'd have eroded almost as quickly as the grikes, and there'd have been no pavement. It's slightly odd to think that these dramatic and relatively extensive features are so young (on a geological scale): thousands of years old rather than millions or even tens of thousands.
Limestone pavement is of particular interest to ecologists for nationally-scarce plant species able to thrive in the specific chemical and climatological conditions. Crevices in the exposed faces are frequently occupied by spring therophytes, plants which complete their entire lives during a brief period in spring, as summer conditions are too harsh. Grikes, which may be 6 m deep (more typically 1-2 m) and 1-500 mm wide, offer shelter from these extreme conditions and grazing, plus soil, so support rare plants, many more usually considered woodland species.
This particular exposure is protected from grazing, which has allowed greater colonisation by vegetation than is usual for the environment, even including trees (mainly Ash (Fraxinus excelsior)). Beyond the immediate surface, availability of water to plants is dependent on networks of cracks in the limestone, which are constantly and rapidly evolving. I wonder whether that's what killed these bare trees.
In addition to its beauty and scientific value, this is also a threatened environment, large areas originally having been destroyed to create agricultural land and more recently for decorative blocks of limestone for gardens. Since 1981 and the Wildlife and Countryside Act, Limestone Pavement Orders have afforded some legal protection: disturbance, damage and removal of limestone are offences which, incidentally, apply to individuals taking souvenirs as much as they do to commercial clearance. So don't.
More specifically, 5769 ha of Ingleborough have been designated a Special Area of Conservation (SAC) by the European Commission, as this is the largest of only four sites in northern England exhibiting pavements on Carboniferous limestone.
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