Calculates age to breast height, according to Elfving 2009. At the National Forest Inventory the determination of stand age is generally based on counting of year rings on increment cores taken at breast height from basal area mean trees. To get total stand age a value for ―time to reach breast height‖ is added. This value (T13) is selected from a table and depends on species, site index according to site factors (SIS, m) and latitude (LAT, N). The values in this table have been smoothed with the following regression: T13 = 37 – 0.605*LAT – 1121/SIS + 21.92*LAT/SIS + 29.5*ISSPRUCE/SIS ; https://www.heurekaslu.se/mw/images/9/93/Heureka_prognossystem_%28Elfving_rapportutkast%29.pdf (page 55)

'Declaration
 
Public Class AgeToBreastHeightElfving 
   Implements Slu.Heureka.DomainLayer.PluginHandling.IPlugin 

'Usage
 
Dim instance As AgeToBreastHeightElfving

public class AgeToBreastHeightElfving : Slu.Heureka.DomainLayer.PluginHandling.IPlugin  

public ref class AgeToBreastHeightElfving : public Slu.Heureka.DomainLayer.PluginHandling.IPlugin