Flora of Ashdown Forest - Botanical Society of the British Isles

One plant on a vertical, north-facing rock beneath an 80% canopy cover of birch,mountain ash and pine in replanted ancient woodland (47.26), 1993, RN et al. It survived thesevere summer drought of 1995 well as the rocks stayed damp through most of the summer.In 1994, one small part of the patch was peeling off and dy'lng, so it was transplanted to a3 -f-I--------'+_nearby ledge where it has subsequently grown and spread.Tunbridge filmy-fern was first found at Tunbridge Wells by G. Dare in the 1600s (hencethe name), and has been recorded in about 20 localities in south-east England. Most sites are4 5 concentrated in the Ardingly and Tunbridge Wells complexes of sand rocks in the north of theWeald, with Furnace Wood as an interesting outlier. In 1994/1995 a total of 77 patches werefound in 24 colonies in twelve sites (six of these have only one plant), and it was probably extinct in eight sites, a 68%decline in the number of colonies and 20% loss of sites since the 19505 (Rich, Richardson & Rose 1995). The decline isdue to a combination of loss of woodland cover, dense shade especially from rhododendron, and storm damage;historically, collecting and public pressure have also caused losses.Tunbridge filmy-fern is one of a number of western oceanic or Atlantic species most frequent on the west coasts ofBritain and Ireland which are also found in the mild, damp climate of the We aid in Sussex and Kent (e.g. Dryopteris aemula,Wah/enbergia hederacea; Rose 1952). It is characteristic of steep, porous sandstone rock faces usually surrounded bydeciduous woodland with a particular microclimate, and it often grows with Atlantic bryophytes. It occurs locally inwestern Europe and Macaronesia.POl YPODIACEAEPolypodium. Polypodies.British Po/ypodium is composed of three segregates forming a polyploid series with hybrids. P. cambricum has two sets ofchromosomes and has not been found. P. vulgare s.s., with four sets of chromosomes, and P. inter/ectum, with six sets,have been both recorded. The records have all been checked under a microscope; P. vulgare has 10-13 thick walled cellson the annulus, and P. interjectum 7-9. The hybrid between them has misformed spores and is reputed to be frequent.The old records - Ashdown Forest, 1895, T. Hilton IBTN). and all the records in Hall (19801 - are for the aggregate P.vulgare sensu lata.We have mapped both the aggregate and the two segregates. In the summer drought of 1995 many fronds did notproduce sporangia which prevented us from completing our research into the distribution of the segregates. However,from the data available the two segregates are about equal in frequency, and occur in similar places. They are most typicalof the banks of sunken lanes, as around Coleman's Hatch (45.33). P. vulgare s.s. has been recorded as an epiphyte onlyat Keyward's Wood (504.324), perhaps reflecting the lack of old woodland trees on the Forest. In southern England P.interjectum is reputed to require more hn!':e-rich substrates and be more shade tolerant, and is thought to be the morewidespread species (Stace 1991). The polypodies occur over most of Europe, the Far East, Macaronesia, eastern NorthAmerica and South Africa.31Polypod/urn s.l.Polypodiurn vu/gare s.s.PolypodyPo/ypodium inter/ectumIntermediate polypody3 -+h.-----'--+~3 -f-I--------'+_3 -+t------'--+~4 54 54 5DENNSTAEDTIACEAEPteridium aquilinum. Bracken.Ubiquitous on acidic soils in both Hall (19BO) and our survey, and consequently there are nospecific old botanical records but there are numerous social ones, including a 1274 referenceto it being used by the 'customary tenants' for fuel. Bracken was one of the main products ofthe Forest, with one of the ancient commoners' rights being to cut 'brakes and litter'. After 13August bracken was cut by hand by both men and women and taken off in carts as shown inthe picture in Glyn & Prendergast (1995). It was used locally for bedding for stock, litter forhens, manuring land and at Woodlands Nursery. It was also sent as far away as Hailsham(pers. comm. J. Waiters, 1995) and even to the London markets. Jenks (1967) notes it was4sold, though this may be illegal as commoners were supposed to use it themselves. In the1950s near Chelwood Gate it was cut by hand, left to dry and then taken in for bedding for pigs {M. Morley, pers. comm.1996(.