Dead and downed woody fuels in forests are commonly estimated using the line intersect method, which requires appropriate values for specific gravity, piece tilt angle, and piece diameter. We present data for these variables for six commercially important tree species based on extensive surveys of slash and naturally fallen dead wood in four regions of the western Canadian boreal forest. The considerable variation by diameter size class, species, cover type, and, to a lesser extent, region suggests that specific values will improve fuel load estimates. We combine the three variables into a single factor so that fuel load (megagrams per hectare) can be simply calculated by multiplying this factor by the number of intersects per meter of sample transect.