Procedures for calculating the moisture contents of 1- and 10-hour timelag fuels have been developed based on theoretical calculations of the rate of moisture transport in wood. The 1 -hour timelag calculation is superior to fine fuel moisture calculations developed previously because there is no regional bias, making it valid over a wider range of conditions, and because it separates out the effects of the environmental factors of temperature, humidity, and solar radiation. The 10-hour timelag calculation produced values reasonably consistent with observations obtained from 1/2-inch ponderosa pine fuel sticks exposed under field conditions.