Simulation model for dynamics of three types of annual plants

A Monte Carlo type model describing dynamics of three pairs of annual plants living in a homogeneous habitat is presented and discussed. Each plant follows its own history with growing, fecundity and survival chances determined individually as functions of the plants condition and environment. The three plants - Valerianella locusta, Mysotis ramosissima and Cerastium semidecandrum differ by the weight of their seeds, which in the model determines the competition preference. Heavier seeds have a better chance for germination from a site containing seeds of different plants. Better colonisers produce more seeds and disperse them over a larger distance. I show that without absolute asymmetry in