# Actions

Actions allow users to cut trees, change stand properties, modify tree predictions, and/or add regeneration at any simulation cycle via commands.

## Defining an action

Use the def command to define a new action, example:

Actions

def MyExampleAction

You can define operability constraints to limit when and/or under what stand conditions the action should be scheduled (Operable command). If no Operable or Lock constraints are stated, then the action will occur immediately and will continue to occur repeatedly until the end of the simulation.

Once the stand is operable, you can:

1) schedule harvest (Cut command),

2) alter stand and/or model properties (Stand command)

3) amend tree predictions (Amend command) , and/or

4) recruit new trees into the stand (Recruit command)

These four activities above can occur as soon as the stand becomes operable and/or can be scheduled to occur in future cycles. Once operable, all scheduled activities (the prescription regime) will be forced to occur, regardless of whether the stand is still operable in future time periods. Following completion of all activities, the stand will be reassessed in each cycle to see whether it meets the same operability constraint. If it does, the activities will be repeated.

Actions

def MyExampleAction

Units {METRIC | USA; DEFAULT = METRIC}

Operable {simulation cycle arguments; DEFAULT = all cycles; must be >= 0 or not stated}

{Conditional stand entry statements…}

Cut {relative cycle arguments; DEFAULT = activation cycle = 0; must be >= 0 or not stated}

{Cut priority rules and retention constraint statements…}

Stand {relative cycle arguments; DEFAULT = activation cycle = 0; must be >= 0 or not stated}

{Stand property alteration statements…}

Amend {relative cycle arguments; DEFAULT = activation cycle = 0; must be >= 0 or not stated}

{Tree prediction modifier statements…}

Recruit {relative cycle arguments; DEFAULT = activation cycle = 0; must be >= 0 or not stated}

{Recruitment statements…}

Lock {# of cycles to lock the action for after activation; must be > 0} {Optional: names of other actions to lock over this same time frame}

### Units

If you wish to use USA (English) units in an Action statements, you must state ‘Units USA’ within the scope of each Action definition as shown above. Default units are METRIC.

### Scheduling actions and activities with cycle arguments

The simulation cycle(s) an action is permitted to occur in can be explicitly controlled by the Operable statement by specifying those simulation cycles after the Operable command. For example, Operable 0 4 would constrain the action to simulation cycles 0 and 4; assuming all other (if any) stand conditional constraints are satisfied. If years per cycle equals five, then cycle 4 would equal year 20 in the simulation. If no cycle arguments are specified following the Operable statement, then the stand is continually reassessed for operability by looking for and evaluating any stand conditional constraints that may be stated under the Operable statement. You can also use the Lock command to restrict the stand from becoming operable again for a fixed number of cycles after the action has occurred.

In a similar way, activities (Cut, Stand, Amend, or Recruit) within an action can be scheduled to relative cycle(s); relative to the simulation cycle that the action becomes operable in. For example, if Cut 0 is stated, then the cut activity will occur in the same cycle the stand becomes operable. If Cut 2 4 is stated, the cut activity will occur two cycles after the stand becomes operable and will then occur again after two more cycles (four cycles post operable). By default, if a cycle argument is not stated after the activity command, the activity will occur in the same cycle the action becomes operable in.

## Deleting an action

Use the del command to delete an existing action. An action will continue to be scheduled in subsequent simulations if not deleted.

Actions

del Clearcut

Or inline format:

Actions.del Clearcut

Note: You do not need to delete an action to change an action definition. Simply restate the action with the same def name and the action will be overwritten.