SECTION XII 



CLASS VIII. CHERSOPHYTES. FORMATIONS ON 



WASTE LANDi 



CHAPTER LXXVI. WASTE HERBAGE 



In many regions where the rainfall and atmospheric humidity are 

 sufficient for the existence of forest or shrub-land, there may occur on 

 particular dry kinds of soil, such as limestone rocks, stiff clay, and so 

 forth, communities of xerophytic perennial herbs. These often have 

 arisen as a consequence of the destruction of forest and shrub-land, yet 

 they must often be regarded as natural formations. Despite many 

 points of resemblance to steppe they must be distinguished from this. 

 The more prolonged vegetative season and greater atmospheric humidity 

 cause their vegetation to be composed of species and growth-forms foreign 

 to true steppe. The communities in question are, as a rule, also much 

 poorer in bulbous and tuberous plants than is steppe. As examples we 

 may mention the following : 



Festuca valesiaca meadow on the Alps. Most steppe-like is that 

 consisting of Festuca valesiaca, which occurs in dry Valais on sunny, arid, 

 places where the soil is shallow. The dominant species, Festuca valesiaca, 

 forms small cushions composed of numerous densely packed shoots, 

 which display many capillary, folded, glaucous radical leaves and stiff 

 haulms 10-30 centimetres in height. Between the grasses grow various 

 perennial herbs, including bulbous plants (Gagea saxatilis and Mus- 

 cari comosum). Among the grasses rolled leaves are common, and are 

 possessed by Festuca valesiaca, Koeleria valesiaca, and Stipa pennata ; 

 and some grasses, including Poa bulbosa and P. concinna, have tubers 

 which serve as reservoirs for water or nutriment. The commonest devices 

 adopted to guard against desiccation are the production of hairs (in 

 Oxytropis Halleri and Artemisia valesiaca), succulence (in Sempervivum 

 arachnoideum), and diminution of the assimilatory surface (in Onobrychis 

 arenaria and Plantago serpentina). 



Brome meadow on the Alps. Less xerophytic is brome meadow 

 in which Bromus erectus dominates. It occurs particularly on dry 

 sunny sites on calcareous soil. Among the companion-plants we may 

 mention Galium mollugo, Festuca rubra, F. ovina and F. pratensis, 

 Arrhenatherum elatius, Carex montana and C. verna. Prunella vulgaris. 

 Salvia pratensis, and others.- 



In Montenegro. Belonging to this category we must probably 

 regard Montenegrin expanses of poor grassland occurring on stony ground, 

 and thus providing a transition to fell-heath which is described in the 

 succeeding chapter. Hassert ^ says of them that they clothe extensive 



' See p. 136. ' Stcbler unci Schroter, 1889, 1892. ' Hassert, 1885. 



WARMING U 



