CROBAS (
Because of the structural rules and simple geometry, 12 of the 13 state variables are bound together through linear or allometric equations in balanced growth (for treatment of disturbances to balanced growth, see Mäkelä 1999). Because of its key role in production, foliage mass (Wf) is used as a representative variable of the mutually related variables. The variable not bound to the rest is the length of the bare bole (Hs), the development of which is largely controlled by the local environment of the tree and cannot therefore be derived from a tree balance only. Crown rise is mainly determined by stand density and crown coverage in CROBAS. Detailed descriptions are given in
Table. Tree structure variables used in CROBAS.
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