Shibusawa et al.
(Shibusawa et al., 1992, 1993; Shibusawa, 1994)
performed observations of a root system of corn and
applied a stochastic L-system to model it. A cellular
automaton was also applied to produce a model of root
growth (Itagaki et al., 2006), where the direction of
root elongation was determined by the probability of
surrounding cells around the root tip.