What have the L-systems (Lindenmayer systems) been actually used for in biology?

From Wikipedia:

An L-system or Lindenmayer system is a parallel rewriting system and a type of formal grammar.

L-systems were introduced and developed in 1968 by Aristid Lindenmayer, a Hungarian theoretical biologist and botanist at the University of Utrecht. Lindenmayer used L-systems to describe the behaviour of plant cells and to model the growth processes of plant development.

I tried to find biological research that has actually used this system but I could not find any. Perhaps this is because I do not know biology that well.

Are these models important? Still taught?

They do produce pretty pictures (again from Wikipedia)