The distribution of Senecio vulgaris: capacity of climatic range models for predicting adventitious ranges

The distribution range of Senecio vulgaris L. is climatically modelled using its archeophytic range and the monthly means of precipitation and temperature. In a first step, the frequency distribution of the range and a buffer area along the climatic gradients are calculated and presented in frequency diagrams. Sharp and gradual climatic range boundaries have been observed and their implications for climatic models of plant ranges are discussed. The buffer area proved to be valuable in assessing apparent climatic range boundaries where the range is not limited by environmental factors but by geography. In the climatic model of the range of S. vulgaris there were considerable congruencies in its archeophytic and its neophytic parts. Climatic modelling of plant distribution ranges may contribute significantly to the understanding of the adventitious plants' spread. However, the climatic suitability for growth is only one factor affecting the potential of plants as to adventitious behaviour.