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54 HUGO SJORSFig. 6. Coastal oakwood on boulderysoil. Comparatively rich"meadow" type with Stellariaholostea, M elica uniflora and Poanemoralis. Osternas, Senoren Island,Ramdala, Blekinge. May 5,1961. Photo B. Berglund. Courtesyof the Skl'me Ass. for Prot. ofNature.to be progeny from planted trees (LINDQUISTl932 b). Such a stand of ash or elm, if left undisturbed,will withstand spruce invasion andprobably be fairly self-perpetuating. The lowerstrata of vegetation and the humus layer (crumbmull) will be entirely dependent on the heavy shadein summer and the abundant leaf-fall in autumnprovided by the plentiful foliage of the mightyelm and ash trees. But with a different start, anequally good soil can become invaded by spruce.The serious drawback of the spruce is its slowinitial growth as compared to the quick-startinghardwoods, and its advantages are tolerance toshade, to deterioration of the humus, and to fairlystrong grazing.Groves of hazel (Oorylus avellana) are frequent,either with or without an over-storey of trees. Theyare mainly a feature of the former pastoral landscape,often originating from "park-meadows"in which the usual back-cutting of the hazel is nowneglected. Although the hazel increases at firstafter abandonment, it finally becomes overshadedby forest trees (ash, elm or, most frequently, spruce).The ecological position of the oak is puzzling. Inan imaginary landscape of "climax" forests, therewould obviously be little place left for oaks, butin the real world the oak has several advantageousqualities which give it ample chances of establishmentand survival. Thus, acorns are easily spread(particularly by jays, which with the present scarcityof birds of prey have become numerous), thegermination is fast and the seedlings are powerful.Contrary to widespread belief, oak grows prettyfast, is not extremely intolerant of shade, gets onwell on poor or dry soils, stands a good deal oftemporary inundation, etc. Its longevity is obviouslyof great importance when trees of otherspecies begin to become aged and need regenerationfor survival. Any forester will hesitate to cut outoak, which as young slender trees is practicallyvalueless, whereas well-grown oak of larger dimensionsmay occasionally fetch a high price. On theother hand, oak seedlings and saplings are extremelysensitive to grazing from domestic and wild animalsand also to attack by rodents (which also mayhamper regeneration simply by eating every acorn).Since grazing in the forests was discontinued, oakseedlings are seen almost everywhere. This regeneration,however, shows no concentration to thepresent oakwoods-on the contrary it now seemsas if the oak were going to gain a position in theconiferous forest itself, young oaks appearing inActa Phytogeogr. Suec. 50