Nodes of different colours represent the following:
Solid arrows point from a submodule to the (sub)module which it is
descended from. Dashed arrows point from a module or program unit to
modules which it uses.
Where possible, edges connecting nodes are
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This subroutine distributes dead root mass through the soil profile
code developed by Armen R. Kemanian in 2008
March, 2009 further adjustments expected
ensures that cumulative fractional root distribution = 1