The Relevance of Current Hazard Stick Reading to the Moisture Content of Logging Slash

Seven composite samples of western red cedar and western hemlock logging slash of 0.25 to 2 inches diameter were exposed on top of and within the bottom third of a fuel bed in the interior wet belt of British Columbia in August 1965. Their moisture contents were measured regularly 24 hours a day and compared with the moisture content of an exposed B.C. hazard stick on the basis of both the hourly drying rates on 1 clear day and the daily loss of moisture, relative to the morning maximum moisture content, for a period of 6 drying days after rain. The absolute moisture content values, the hourly rates of drying, and the daily fluctuation of the moisture content of the hazard stick differed from those of the fuel samples at all times. It was concluded that cedar-hemlock slash fuel moisture content cannot be predicted numerically from an individual measurement of the moisture content of freely exposed hazard sticks in those years when the slash retains a tight bark. Counting the number of drying days after rain proved to be of little practical value.