FIGURE 3. Vegetation shift from indigenous deciduous to exotic evergreen broad-leaved vegetation in southern Switzerland.
From the following article:
Ecological responses to recent climate change
Gian-Reto Walther, Eric Post, Peter Convey, Annette Menzel, Camille Parmesan, Trevor J. C. Beebee, Jean-Marc Fromentin, Ove Hoegh-Guldberg and Franz Bairlein
Nature 416, 389-395(28 March 2002)
doi:10.1038/416389a
The shrub layer is dominated by the growing number of spreading exotic evergreen broad-leaved species (see illustration) that appear to profit from milder winter conditions, indicated here by the decreasing number of days with frost per year (the smoothed curve gives five year averages for the number of frost days per year)29.
