The Establish event establishes the stand at the beginning of a Crop Plan. At that time, a Stand Age and Year must be specified.
Stand age is the reference age for the stand. When the Establish event is executed it represents the elapsed time since the stand originating event, usually a harvest, fire, or other major disturbance.
The Stand Age column in a Crop Plan is used to keep track of the elapsed time since stand origin. The value in the Stand Age column is determined by the Establish event settings.
Year is the calendar year at Establishment of the stand.
A stand may contain trees of differing ages that may become part of the stand by In-growth or Regeneration events.
Trees in the tree list are given a total age and a breast-height age. The adjustment for years to breast height is controlled by a system variable, 15 10 6 20 years for spruce, lodgepole pine, aspen, black spruce respectively in the Alberta Variant. When simulating trees in the Establish event, breast-height ages must be given for each cohort of trees.