Locations of trees in Helsinki 2013

In order to identify individual tree trunks, pallet cover material has first been produced. It was obtained with the help of the NDVI raster and building polygons created from the 2013 regional false-colour image. From the NDVI raster, more than 2 metres of non-building vegetation was selected.

The laser scanning data on which the analysis is based contains noise in the north-eastern parts of Helsinki, for which nothing could be done and which causes the crown cover in the noise area to be slightly lower than it actually is.

The location of the stems was determined by using a canopy cover to find the highest point of the canopy using a default diameter of 3.5 m for the canopy.

The data was produced in the Decumanus project by the German Space Research Centre DLR. The material is available from HSY's map service at https://kartta.hsy.fi