On the wettability of sapwood and heartwood of various woodspecies (Pine, Douglas fir and larch) Results have established that the wettability of sapwood from three woodspecies (Pine, Douglas ®r and Larch) on the cross, radial and tangential section with water and various glues (UF-resins, PF-resins, MUPF-resins and PMDI-adhesive) is better than that of heartwood. In most cases, the tangential section in sapwood and heartwood was less wettable than radial and cross sections. Using alkaline phenolic resins which cause wood to swell, wettability in the tangential direction was improved.