A simplified diffusion model was developed to describe the distribution of moisture in (pine)wood in the 1(st), and 2(nd) periods of drying and esp. the distribution and evolution of stresses. Model-based moisture and stress distribution curves are given. In the 1(st) period, nonuniform water distribution made no stress arise. In the 2(nd) period, stresses reverted and built up to exceed the mech. strength of the wood, and cracks appeared. The acoustic emission method monitored the developing cracks satisfactorily.