Flora of Ashdown Forest - Botanical Society of the British Isles

ica tetralix. Cross~leaved heath.Ashdown Forest including white-flowered plants (Col em an 18361. Ashdown Forest, E. Jenner(Arnold 18871. On the Forest (Firmin 18901. Ashdown Forest, 1892, E. H. Farr (BTNI.Ashdown Forest, white form, 1910, Miss P. Stockdale (BEXI. Ashdown Forest (Done 19141.White form at Twyford (Dent 1928-19531. Common on the Forest (Hall 19801.Surprisingly, cross-leaved heath has not been found in sixteen of the squares we havesurveyed. It is restricted to the wetter heathy soils of the Forest, where it is found inassociation with Molini8, Sphagnum and low Cal/una cover. Where apparently pure stands ofCal/una have been mown in the past ten years, the regenerating heather now has a highproportion of Erica tetralix, as for instance near Gills Lap (466.314). It may be able to toleratethe effects of water-logged environments as it is shallow-rooted, but freedom from competition from Cal/una and E. cinereawhich do not tolerate the conditions well is also important is allowing it to dominate the vegetation.Decreasing in England (Rich & Woodruff 1996). Widespread on suitable acidic soils in western Britain, rarer in theeast. A western European endemic.Erica cinerea. Bell heather.Ashdown Forest, including white-flowered plants (Coleman 18361. On the Forest (Firmin18901. Ashdown Forest, 1910, Miss P. Stockdale (BEXI. Ashdown Forest (Done 19141.White forms at Twyford and Duddleswell (Dent 1928-19531. Common on the Forest (Hall19801.3Bell heather was found in all but seven squares during the fieldwork, which is surprisingbecause it is the least abundant of the three heathers on the Forest, occurring only in the driestareas. It is frequently found as scattered plants, often on the edge of fire rides where soil4 5disturbance has resulted in drier ground. Erica cinerea, E. tetralix and Cal/una can be foundtogether particularly on rides.The reproduction of bell heather by seed has been described by Bannister (19651. Plants will flower in July and earlyAugust from their second or third year onwards. Flowers may be self~ or cross~pollinated. Ripe seed can be obtained asearly as September, but most is shed in October and November. Each capsule contains 18~34 seeds (one third of whichmay be abortive), each plant producing on average about 5000 seeds. Seed dispersal is poor and seedlings usually occurnear the parents. Seed germinates immediately it is shed, or intermittently thereafter and seeds may be long~dormant.Germination is stimulated by light, alternating temperatures and short heat shock (i.e. fires). A mycorrhizal fungusassociation with the roots appears to be essential to seedling survival, recycling nitrogen from the decaying litter to theheathland plants. Seedlings establish better on mineral than organic substrate, and on moist rather than wet soils.Plants grow best in open conditions, but will tolerate shade down to 15 % of daylight reasonably well and flowersparsely; between 15% and 7% of daylight it only survives as a straggly, weak, non-flowering plant. It often grows as anunderstory to heather, and will grow in open woodland but does not survive in deep shade. It does not germinate well onwet soils occupied by E. tetralix and is killed rapidly if the water table rises, perhaps due to sensitivity to ferrous ions in theground water.Still widespread in Britain on acidic soils but decreasing (Rich & Woodruff 1996). Mainly western in Europe.*Erica vagans. Cornish heath.The Crow borough record where it was recorded naturalized on forest land in the Crowborough Guide 1930 was acceptedby Wolley-Dod (19371; 1(. E. Bull reported that in 1972 the site at Camp Hill was much overgrown and it could not berefound (Hall 1980). Press Ridge Warren, near garden, 1945, G. Dent (Dent 1928-1953). It has not been seen recentlyand is probably extinct.Currently it is native in Cornwall where it forms extensive heath on the Lizard, and appears to be a classic Lusitanianplant. However, according to F. J. Hanbury it grew luxuriantly in the rock gardens at Brockhurst, East Grinstead (Hanbury1917) so it is perhaps not climatically limited to Cornwall. It is endemic to western Europe.Erica sp.An unknown Erica was found on the edge of a path near Chelwood Vachery (c. 435.2961, 1990-1994, NM & CM, butcould not be refound when needed for identification. It will have to be checked again, and may be one of Winnie-the­Pooh's 'spotted or herbaceous backsons'.Vaccinium oxycoccos. Cranberry.Bogs in Hindlip Warren, Ashdown Forest, on the eastern branch of the Kidbrooke stream, 31 August 1836 (Coleman 1836;LlV). Searched for several times in 1994 and 1995, TR, without success, the whole area now being woodland or denserhododendron. Old maps indicate areas of Sphagnum bog where it could have occurred at Hindleap.Cranberry is now a very rare plant in the Weald, with only three localities remaining in Sussex (Briggs 1990), two inSurrey and only a few sites in Hampshire in the Woolmer Forest area. Sphagnum bogs are generally very small andscattered in the south and prone to drainage or scrub invasion, and it has gone from most former sites in southern Englandbut still lingers in Norfolk. It is more widespread in the north and west where there are larger areas of bog. In Europe it iswidespread in the north and centre. It also occurs in Asia, North America and Greenland.81