A study measured the drill resistances of larch and Scotch pine by a drill resistance technique and compared the densities of the same specimens measured with a traditional volumetric method. The drill resistance technique was found to be a good measure of the density profile of wood to reflect tree rings and defects (knots, decay and hollows). The drill resistance technique as applied to pines uses a linear relationship between the wood density and the average drill resistance. This technique has the applicability and possibility as a possible method for the density measurement and the defects detection. The technique is rapid, inexpensive, safe, portable and has the potential to be adopted as an on-line density profile method.