Miscellaneoi:is Studies 



Long -log scaling tables 



On the Alaska national forests, the maximum scaling length is 40 

 feet. Pieces from 42 to 80 feet are scaled as 2 logs; from 82 to 

 120 feet as 3 logs, etc. To facilitate scaling, long-log Scribner, 

 Decimal C board-foot tables were made based on a 1-inch per 6-foot 

 taper. They are being used for scaling Ketchikan Pulp Company logs 

 but there has been some question as to their accuracy. 



Rafts from many locations within the Ketchikan sale area were 

 sampled, the sampling being allocated by log production of the 

 vario\js camps. Every tenth piece was measured \:tsing a steel tape 

 and the volumes by the usual scale of individual logs compared with 

 those obtained by long-log table. The ratio between the first and 

 second method was 0,9796, The standard error of this ratio is 

 ^ ,0055 • The difference between the two scales is statistically 

 significant and not due to sampling errors. This difference is 

 caused by the fact that the sample had a taper of 1-inch per 6,9 

 feet whereas the long-log tables were based on 1-inch to 6 feet, 

 Fran a practical viewpoint the 2.09/O difference is of minor importance 

 as a one or two percent difference in gross scale is usually accept- 

 able in check scaling. 



On the north half of the Tongass, the Assistant Supervisor made a 

 direct comparison of the two methods by scaling 1? rafts totaling 

 over 6 million feet. He obtained an aggregate difference of - 0,13 

 percent and an average difference per raft of ♦ 2,25 percent. It 

 would seem that the difference in scale is negligible. An analysis 

 of data by location of rafts indicates that the rate of taper 

 increases from the south to the north portion of the region. There- 

 fore the 1-inch to 6-foot taper is representative for spruce and 

 hemlock on the Tongass, It should not be lised for cedar as this 

 species has greater taper. 



Fire weather in Southeast Alaska 



In ovr 1954 report it was shown that the moisture content of fuel 

 sticks on the small cutover area then available fell below 15 percent 

 several times during the summer season. These were only weekly read- 

 ings. During the season of 1955, readings were taken daily at 4^30 p,m, 

 on a 250-acre segment of the large clearcut in Maybeso Valley, a much 

 more typical area of pulptimber cutting. The record included air 

 temperat^ire , relative humidity, wind velocity, 24-hour precipitation 

 and fuel moisture content as indicated by Region 6 sticks. 



During the period June 25 to September 30 fuel moistiire dropped below 

 15 percent, the point at which litter can be ignited in the Pacific 

 Northwest, on 37 days. The longest period it stayed below 15 percent 

 was 7 days; the average 3 -7 days during the 10 periods this happened. 

 Fuel moistiore dropped below 10 percent on 6 days during 4 periods and 

 reached 8 percent, the lowest recorded, on 3 occasions. 



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