326 MESOPHYTES sect, xvi 



dicotylous woodland, seems in general to be the form of vegetation natural 

 to river-plains in the temperate zone. As our information in regard to 

 these communities is very incomplete, it is impossible to assign them to 

 their correct position. 



The same is true of the ' grassland of the creeks ' in Usambara, of 

 which Engler ^ writes : ' A little above the sea-level there extend inland, 

 often for miles, great sand-fields or stony tracts, which are for the most 

 part under water during the rainy season.' Here grow Cyperaceae, 

 Eriocaulonaceae, Ipomoea Pes-caprae, and other plants. 



CHAPTER XC. PASTURE ON CULTIVATED SOIL 



From meadow to pasture is no great step. The difference depends 

 particularly upon moistness of soil. Pasture is higher and drier ; it is 

 exposed to no greater amount of moisture than that brought by ordinary 

 atmospheric precipitations. The vegetation of pasture is shorter and 

 more open than that of meadow ; often it cannot be mown, but only 

 grazed over. The driest pasture, in which deep-rooted herbs preponderate 

 over grasses, may be termed ' waste herbage ' (German ' Trift '), and 

 merges with the chersophytic vegetation described in Section XII. 



Pastures in the plains of northern Europe, and other regions that 

 were formerly clothed with forest, are almost without exception artificial 

 products : were the human race to die out they would once more be 

 seized by forest, just as their soil was originally stolen from forest. Excep- 

 tions to this rule are provided only by small patches of meadow in old 

 forests, that have been regularly grazed over and manured by wild 

 animals. Spiranthes spiralis is described as being characteristic of such 

 stations in certain parts of northern Germany. Pasture usually consists 

 mainly of grasses, which over a large part of Europe belong to the same 

 species, namely Festuca rubra, Lolium perenne, Anthoxanthum, Poa 

 pratensis, Agrostis vulgaris, species of Bromus, Triticum repens, Holcus 

 mollis ; even in the Italian pascoli one finds many of these species. But 

 an essential part is also played in pasture by dicotylous herbs such as 

 Taraxacum, Leontodon, Bellis, Chrysanthemum Leucanthemum, Achillea 

 Millefolium, Campanula rotundifolia, species of Plantago, Ranunculus, 

 Cerastium, Trifolium, Daucus, Pimpinella, and Carum. Many mosses, 

 including species of Hypnum, may be interspersed. 



The composition of the flora is of slight interest, because pasture has 

 been so metamorphosed and modified by cultivation, in accordance with 

 the use to which the farmer puts it. A number of associations will certainly 

 in the future be distinguished. For instance, R. Smith ^ recognized in 

 Scotland pasture of the basalt hills, pasture of the Silurian hills, and 

 pasture of the Pentlands. Furthermore, experience has taught us that 

 water plays a very important part in regard to pastures, and that the 

 constituent plants are easily affected by it. On p. 45 it has already 

 been noted that Feilberg showed how the vegetation on the plains near 

 Skagen in Jutland changes with the level of the water-table. According 



^ Engler, 1894. * R. Smith, 1900 a. 



