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292 BENGT PETTERSSONFig. 5. Wooded meadow with theoriginal structure preserved. Ulmusminor ( carpinijolia) and Fraxinusexcelsior have been cut forleaf-fodder; the oaks (Quercusrobur), the acorns of which oncewere a valuable nourishment forthe stock of swine, are unaffected.The hazel (Corylus avellana) iscut down at intervals. The swardis very rich in grasses and herbs.Pollen analysis has shown that thetrees and shrubs are descendantsfrom an original deciduous forest.Gotland, Lokrume, Haltarve. May20, 1946. Photo Bengt Pettersson.(mainly on morainic soils) were burned at intervalsin order to obtain certain crops (even includinghay and pasture). This has lastingly influencedboth the woody vegetation and the entire flora, ashas been reported from Skane by GuNHILD WEr­MARCK ( 1953).During the 19th century the country sufferedfrom overpopulation and people were enforced tomake use of marginal land which had not previouslybeen cultivated. In South Sweden the intenseburning and grazing enlarged the Calhma heathsand had a disastrous effect on the remaining forest,the area of which shrank considerably (cf. MALM­STROM 1939, M. FRIES 1958b, IVARSSON 1962).On the other hand the Calluna heath now invadesformer grassland as a consequence of ceased grazingduring the last few decades, but this developmentis merely a transitional stage towards closed forest(BERGLUND 1962, p. 418, and 1963, p. 73).The forest was of comparatively little value to theancient rural economy, but gradually the importanceof the timber increased and reforestationbegan. The kinds of vegetation that were dependenton continuous grazing disappeared under the densestands of self-sown or planted coniferous trees orunder high-growing Calluna. Among species diminishingor disappearing in many districts underthe new conditions should be mentioned Pulsatillavulgaris, P. vernalis, Lycopodium tristachyum andBlechnum spicant.Modern forestry has profoundly changed thevegetation of woodland in most districts of thecountry. The ground has often been artificiallydrained and in the lowland areas many of the mireshave been turned into forest (cf. HoLMEN 1964,p. 10). The domestic animals that earlier weregrazing in the forests have been removed, since theywere said to obstruct the regeneration. The consequencesof this change in management have notbeen merely in the negative. Deciduous trees andshrub have spread in the formerly grazed coniferouswood, e.g., oak and birch have grown up, and hazelespecially on better soil. Many species of theground-flora sensitive to heavy grazing have alsospread, for instance many orchids on Oland andGotland, and Convallaria majalis, Anemone nemorosaand other species of shady habitats show adistinct trend towards increasing their distributionand abundance, except in the vicinity of the largecities.The creating of extensive clearings in the foreststhrough modern logging methods has also broughtabout many changes, especially in connection withceased grazing by domestic animals. Instead ofActa Phytogeogr. Suec. 50