A number of potential fumigants were screened with respect to their toxicity to decay fungi, (Poria carbonica, and Lentinus lepideus) and their sorption characteristics on Douglas Fir (Pseudotsuga menziesii Mirb. Franco) wood. Wafers of infected wood were exposed to different fumigant concentrations for various times then cultured to determine viability. The lethal concentration X time (ct) factors were determined for each fungus species and fumigant chemical. The "pulse chromatograph technique" was used to determine sorption isotherms for the fumigants to establish the relative degree of interaction between the chemicals and wood. Formaldehyde, chloropicrin (trichloronitromethane), and methylisothiocyanate (MIT) were the most fungitoxic of the chemicals investigated. MIT had the strongest affinity for wood, suggesting that this fumigant should persist longer in treated wood than chloropicrin. The proportion of vapor adsorbed on wood increased greatly with decreasing temperature and was generally higher in decayed wood than in sound wood and in 8% moisture content wood than in dry wood.

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