ON THE MODELING OF CLONE GEOMETRY IN ASARUM-EUROPAEUM

A geometric model of an overground creeping herb is presented. The aim of modelling is to reveal interdependencies between local growth rule s (i.e. branching angle) and overall characteristics of a clone (i.e. biomass, square, borderline irregularity etc.). The correlation betwee n branching angle and lateral branches growth probability is revealed. In the case of high probability of branching (i.e. close to the apica l growth probability) the branching angle is about 50 degrees (in the case of Trifolium repens). In the case of low probability of branching (about three times lower than apical growth probability) the branchin g angle is close to 80 degrees. This is the case of Asarum europaeum, the creeping herb possessing a low probability of branching. The model also permits analysis of the dependencies between four hypothetical l ocal strategies of searching the apical growth direction of a plant an d the overall biomass of a clone. The result is that straightforward a pical growth leads to maximal biomass and maximal clone square, while any other choice of growth direction dependent on local shoot density does not. (C) 1996 Academic Press Limited