  The Horton-Strahler ordering method, originating in hydrology, formulates the
hierarchical structure of branching patterns using a quantity called the
bifurcation ratio. The main result of this paper is the central limit theorem
for bifurcation ratio of general branch order. This is a generalized form of
the central limit theorem for the lowest bifurcation ratio, which was
previously proved. Some useful relations are also derived in the proofs of the
main theorems.
