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In Switzerland, in those valleys in which the glaciers are melting away, leaving stretches of bare mud, scratched stones, and polished rock, plants immediately begin to settle there. A Swiss botanist watched the process during five or six years, and describes how first the yellow Saxifrage (_S. aizoides_) establishes itself. Next season Coltsfoot, willow-herb, Oxyria, and two grasses had planted themselves. During the third season another grass came in. By the fourth season, Fescues and yarrow had appeared, and by the fifth season, five grasses, clovers, and yarrow had formed a regular grassland upon the new untouched soil.[104]