The productivity of forests is typical expressed with a Site Index giving the height of selected trees at a specific age, e. g. the average height of the 100 highest trees per hectare at the age of 100 years. If the height development over age is known, the site index can be estimated using age and height or height and height increment. Maps giving repeated height measurements could be used to create maps showing the site index. We compare site indices calculated using heights from areal images and heights from satellite with those estimated using a site specific model. To get reliable site indices the height increments need to be observed with high accuracy. Low precision could be handled by aggregating some surrounding pixels.
