L-systems [5] generate a tree's branching structure using
axioms and rules in a concurrent context-free rewriting
system. L-systems have been extended in many ways. The
extension most relevant to our work is [7] in which Lsystems
are enriched with partial differential equations and
can be parameterized to reconstruct the shape of a specific
tree or plant. We chose not to investigate L-systems, or Weber
and Penn's parametric tree model [8], for this application
because particle flow from recorded branch tip positions
closely matches the data collected in motion capture.