The natural durability of sapwood of most species is generally low, while heartwood can be more resistant to biodeterioration. For the sawmill industry various lumber products require certain diameters and lengths of the logs in addition to requirements for wood properties. When utilising the heartwood, it is therefore important to acquire information already in the forest about which trees that can be suitable for logs with a predefined heartwood diameter and length. This paper combines results from previous studies on modelling heartwood diameter profiles in standing tree based on the outer diameter profile of the tree with results on acquiring data describing the outer diameter profile based on terrestrial laser scanning (TLS). The basic principle of laser scan measurements involves the emission of laser light pulses towards an object. A pulse hits the object and is reflected back to a sensor. The angle of laser pulse emission and reflection, together with the time between laser pulse emission and return are used to record highly accurate X, Y and Z co-ordinates for each point of reflection. Several million reflection points can be collected per scan, collectively referred to as a point cloud. TLS data can be processed and converted to stem files describing the diameter profile from the base towards the top of a tree. The results presented in this paper show that: 1) the heartwood diameter along the stem in mature Scots pine can be predicted based on measurements of the outer diameter profile from base towards the top, and: 2) the outer stem diameter profiles of standing Scots pines can be non-destructive measured by means of TLS prior to harvest. Combining these two approaches enables pre-harvest bucking simulations for optimal utilisation of the wood resources. This method can be used to evaluate if a pine stand can produce logs with heartwood diameter suitable for products with specific requirements for heartwood content (e.g. external cladding or window frames).

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