SORTIE-NDSoftware for spatially-explicit simulation of forest dynamics
Senescence mortality provides for an uptick in mortality rates. It is meant to slightly increase the death rate among large adult trees.
Trees killed by this behavior will have a mortality reason code of "natural".
Parameters for this behavior
How it works
All trees to which senescence is applied are evaluated for senescence mortality. In practice, trees below the onset of senescence DBH very rarely die. The probability of death rises with DBH until the DBH of maximum senescence rate is reached, at which point it levels off.
To assess whether a tree will die due to senescence, the following function is evaluated:
The probability is compared to a random number to determine whether the individual tree will die.
How to apply it
Senescence may be applied to saplings and adults of any species. It cannot be applied to seedlings.