A comparison was made of the plant communities characteristic of the Mediterranean type climatic regions of France, California, and southern Australia. Infertile and relatively fertile soils support two distinctive groups of plant communities. In their natural state, the climax vegetations on both soils are dominated by evergreen, sclerophyllous trees in a woodland formation. Grass and herbs form a characteristic understorey on the more fertile soils; evergreen sclerophyllous shrubs are common in the understorey on infertile soils. In drier habitats, the climax woodlands may be replaced by shrub communities such as the garrigue-maquis in France, the chaparral in California, and the heath and mallee-broombush (open scrub) vegetations in southern Australia. In a preliminary study, the characters which Schimper and others had expounded were used to compare the communities of drier habitats. Characteristics such as the presence of evergreen sclerophyllous leaves, lignotubers, and similar life-form spectra pointed to comparable vegetation. In further support of this conclusion, phenological data showed that spring was the season of maximum flowering and shoot growth of the various plant communities; the dry summer conditions reduced growth to zero except in southern Australia where growth extends through much of summer. © 1969 CSIRO. All rights reserved.
