Flora of Ashdown Forest - Botanical Society of the British Isles

173Mycelis muralis. Wall lettuce.Seven tetrad records (Hal! 1980).Locally frequent in the north-east of the Forest on the damp, more calcareous soils inwoodland, and scattered elsewhere on roadsides, stream sides, brickwork, etc. It is usually amarked calcicole of soils of pH 6 or above (Grime et al. 1988) and may be restricted by soil3 -++._---"''4- type in our area.In Sussex locally frequent in the west and less common elsewhere. Locally abundant inareas of Britain with high rainfall, and widespread in Europe, Asia Minor and North Africa.4 5Taraxacum. Dandelions.Dandelions are one of the major critical groups in Britain which require specialist knowledge for identification. Over 230species have been recorded to date in Britain many of which are probably endemic. Their reputation is so fierce that theystrike fear into the heart of the keenest botanist and only madmen try to identify them; we have therefore coined thephrase "madologist" to describe anyone studying Taraxacum.Dandelions of the British Isles (Dudman & Richards 1995) is an excellent account of the genus which we have used asthe basis for the identification and nomenclature. There are no previous records for the Ashdown Forest area for individualspecies, and East Sussex in general has been poorly worked (Hall 1980). A little help from an expert is essential to getstarted and it simply takes time to learn them - perhaps "this year, next year, sometime, never" as measured on thedandelion clock. Our records are based on the results of a survey by Jan Kirschner, the Czech expert, during Easter 1995.John Richards has kindly looked through the material we collected and corrected a few names; the material is now held inherb. PH. Not surprisingly our records for the critically determined taxa largely coincide with squares visited by Jan.Taraxacum genusNumber of species determined(# ~ 11)Squares recorded by Jan Kirschner4 54 5Dandelions initially all look the same and yet different to the untrained eye, but once they are known there are manyslight differences which define the species. Most, if not all British species are agamospermous (producing by seedswithout the usual sexual process). Even if insects are observed visiting the flowers, as brimstone butterflies do on theForest in April, they are not cross-fertilising them.To make identification of the species more manageable, the genus is broken down into nine sections in Britain, four ofwhich occur in our Flora area. It is not possible to identify every individual dandelion at the moment, and the techniqueemployed is to look for species which are known, then collect and learn new species. Identification needs to be based onplants carefully selected in the field, which are then pressed for later reference. Plants should be collected soon after theycome into flower for the first time, usually in mid-April, so that the outer leaves can be collected with a young floweringhead.Plants flowering in summer or growing in shaded, trampled or frequently mown places, or those with damaged,infested or diseased leaves should be ignored.Dandelions have been recorded in every square on the Forest. We would expect at least 50 species from the Floraarea, but to date have named about half that number. The distribution maps reflect first the areas that we recorded, andsecondly the richer dandelion areas because experience rapidly indicated that the central areas of the Forest were very poorwith few species.The habitat determines which species are likely to be found. The main habitats for Sections Hamata and Ruderalia arehedgebanks, road verges, meadows and waste land in the villages, where they occur in disturbed, open vegetation onrelatively nutrient-rich soils. Section Celtica species occur on nutrient-poor grasslands - these are likely to be the originalnative species of the area. Section Erythrosperma species occur in dry, open habitats. Dandelions are rarely found inheathland or in woodlands, and consequently Ashdown Forest does not have many species.British dandelions are not representative of the genus as a whole. Elsewhere in Eurasia there are many diploid sexualspecies, and plants may have white, pinkish or reddish flowers, they can have more than one flowering-head on eachscape, they may flower in the autumn, have leathery leaves or flower without any leaves visible at all. World-wide thereare about 2000 species, with the greatest diversity in the mountains of central Asia.