the present time this aspect of the projection logic has not been implemented. When 

 the stand computations have been completed, a subroutine MERGE is called to merge the 

 stand projections with the tree projections and to provide any feedback of information 

 that would indicate a need to modify the individual tree growth projection functions 

 or, alternatively, the stand growth projection functions. The final subroutine in 

 the projection cycle is DISPLY that serves to bring out the displays of the growth 

 prognosis and to accumulate the information on growth that is to be used as subsequent 

 input to harvest scheduling algorithms. This completes the projection cycle and the 

 flow of control in the program returns to TREGRO to start a new growth projection 

 cycle. When all projection cycles for this management alternative have been completed, 

 a new management alternative is introduced for the same stand and a new projection 

 is started. 



If the course of stand development and thinning schedule would be the same for 

 several periods under more than one management regime, then the program would save the 

 redundant calculations by starting the subsequent prognoses from the point where the 

 regimes depart from one another. In turn when all of the management alternatives have 

 been completed a new stand is introduced and the whole process is repeated. 



In addition to these principal subroutines that contain the logic of the growth 

 prognosis itself, there are numerous special subroutines which merely handle repetitive 

 calculations such as sorting, ordering the data according to various attributes, 

 determining percentile in the distribution of those attributes, and related computa- 

 tional details. Copies of the FORTRAN IV computer program and additional documentation 

 can be obtained from the author: 



Albert R. Stage 



Forestry Sciences Laboratory 



1221 South Main 



Moscow, Idaho 83843 



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