A method of obtaining sterilized wood blocks much less drastic than those presently in common use has been developed. The treatment is sufficiently mild that only the most superficial of the living parenchyma cells are killed. Samples of balsam fir wood treated by this technique have been successfully inoculated in specially designed tubes with three fungi that attack recently killed balsam in nature. The technique shows promise of reducing the problem of correlating field and laboratory studies of wood decay by avoiding the marked changes in the wood which result from most sterilization methods.