In the present work fracture (Mode I) was induced through three point-bending tests in two wood species used in timber construction: Maritime pine (Pinus pinaster Ait.) and Norway spruce (Picea abies L.). Load–displacement curves were experimentally determined and corresponding Resistance-curves (R-curves) obtained using an equivalent linear elastic approach. An inverse method is presented to identify cohesive crack properties of a cohesive crack bilinear model used to simulate fracture in both wood species, combining experimental data and a developed genetic algorithm. Good agreement between numerical and experimental load–displacement and R-curves was obtained. Conclusions are drawn from finite element simulations regarding the extent of the numerical cohesive zone computed for each studied wood.