The soils and surface layer geology of the Breckland landscape are
particularly interesting, having been shaped by the tundra-like conditions that
existed here during the Devensian Glaciation. The underlying chalk is covered
by varying depths of sand, and in places sand and chalk may sit alongside each
other at the surface. Under the tundra-like conditions surface layers may have
slid downhill, riding on a still frozen subsoil, while in other places the
lower layers may have 'mushroomed' up following freezing and expansion. Add to
these processes a climate that delivers high summer temperatures, low rainfall
and frequent night-time frosts and you have conditions that deliver an
interesting plant community.
The 'poor' Breckland soils kept agriculture at bay for many generations,
the area dominated by heath and rough grazing up until fairly recently. The
continuity of open habitat may have seen species like field southernwood
survive here for more than 10,000 years but change did come; first with
enclosure and the practise of marling
(using chalk dug locally to improve soil quality) and later with sheep,
rabbit production, forestry and arable farming. The impacts of these changes
have been dramatic, the area of Breckland heath and grassland declining from an
estimated 29,000 hectares at the beginning of the last century to just 7,000
hectares today.
Thanks to recent funding, efforts are now underway to see the
re-establishment of some of Breckland's rarest plant species. Species like the
Breckland, spiked and fingered speedwells, the proliferous and maiden pinks,
and Spanish catchfly may all benefit from the work that is planned. Much of
this work is based around clearing the surface soil to expose the seed bank
beneath, the success of this approach already being seen at sites like Cranwich
Camp. While such 'landscaping' may seem heavy handed on first appearance,
perhaps making site owners somewhat nervous, it is proving a powerful tool for
the restoration of former plant communities. The plans to recover the lost
Breckland flora should once again raise the botanical profile of this rather
special area. With luck, many of those species now restricted to just a handful
of sites will become a familiar sight to a new community of observers, each
with a growing interest in Breckland’s botanical heritage.
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