Meeting report of the South East group of the British Bryological Society, 25 January 2015
A single field meeting can only begin to scratch the surface of the 3500 acre Knepp estate in Sussex. A previous visit by Tom Ottley for a Bioblitz event in 2013 yielded 90 species, and many of the habitats remained to be examined, so this was a much-anticipated trip to a site on the Wealden Clay, which is itself an area that is under-recorded for bryophytes.
Until 2001 Knepp was an intensively-farmed landscape. Since then, its owner, Charlie Burrell, has transformed the estate into the largest re-wilding project in Europe, which has been the subject of much interest. The perimeters have been securely fenced and internal fencing removed, leaving large discrete blocks of land, each of which has been subject to a different treatment. The main block around the castle is home to freely-roaming deer, longhorn cattle, Exmoor ponies and Tamworth pigs.
The exploration began on the wood edges within sight of the John Nash-designed gothic castle, where Cryphaea heteromalla, Zygodon viridissimus var. viridissimus and Rhynchostegium confertum were found on Elder. Since the estate is home to several relatively uncommon trees we occasionally stopped to examine them; a Walnut yielded Syntrichia laevipila, for instance.
David Streeter then led us towards Knepp Lake, a medieval mill pond, pausing on the way to examine the acrocarps on and alongside the track through the wood. Syntrichia latifolia was found on the damp tarmac, along with Didymodon nicholsonii, enabling us to easily compare it with other species from the genus that were also nearby: D. insulanus, D. luridus and D. sinuosus.
Further on, an old hedge afforded an opportunity to compare Neckera complanata and N. pumila, but the most interesting habitat of the day was some old carr woodland. Leptodictyum riparium was abundant, and Oxyrrhynchium speciosum frequent. Three Plagiomnium species inhabited the site: in addition to the expected P. undulatum, P. rostratum and, most significantly, P. cuspidatum were present, the latter notably quite frequent. Leskea polycarpa was another often-encountered species here, and both Hygroamblystegium varium and Scleropodium cespitans were also discovered.
Another area of carr woodland borders Knepp Lake, and the willows along its edge were a fruitful location, providing us with the pretty Orthotrichum pulchellum, plus Cirriphyllum crassinervium, Chiloscyphus pallescens, Bryum moravicum, and more Leskea polycarpa.
Even this short visit has further underlined how rich a landscape this is, and we look forward to the results of the continued surveying of the bryophytes of Knepp.
Many thanks to Charlie and Issy Burrell for their hospitality, hot drinks and cakes, as well as a fascinating introduction to the Wildland Project.