CONCLUSIONS 



The results o£ the three preservative treatment investigations indicate that some 

 care should be exercised in selecting posts and poles from dead trees. The frequent 

 occurrence of long, deep checks and wormholes results in lower quality and a higher 

 cull factor in the dead tree products. In addition, greater care is required in 

 processing the dead tree posts and poles. Posts exhibited a tendency to get stopped in 

 the debarker and to be stripped of an excessive amount of wood, especially as the 

 debarker head was passing over a deep or irregular check on the surface. This problem 

 was not encountered in debarking the poles. 



The, debarked posts and poles vs^ere somewhat rougher on the surface than newly 

 peeled green tree posts and poles. This undoubtedly was due to the lower percent 

 moisture content of the dead tree products. More frequent maintenance of the debarking 

 head may aid in alleviating this problem. 



The steeping method of preservative treatment gave inconsistent preservative 

 retentions for the treating times used. None of the 85 posts treated by this method 

 met the retention specification of 0.30 lb per ft^ (4.81 kg/m^) . The retentions of the 

 study posts ranged from 0.00 to 0.28 lb per ft^ (0.00 to 4.49 kg/m^) . Although the 

 greatest steeping time used was 6 hours, more time than that is needed. There are 

 indications that the time required to treat dead tree posts would be less than the 24 

 hours needed to treat green tree posts. 



Pressure treatment of dead lodgepole pine posts gave directly opposite results. 

 All study posts, including those with bark met the preservative retention specification 

 of 0.40 lb per ft^ (6.41 kg/m^) . A treating cycle of 30 minutes vacuum and 15 minutes 

 of pressure at 100 lb per inch^ (689.48 kPa) , the minimum treating time used, was more 

 than adequate to obtain the necessary retention. The pressure treating time can thus 

 be reduced to about one-twelfth the time needed to treat green posts. 



Of the two treating methods used with poles from dead lodgepole pine trees, the 

 results indicate that the hot and cold bath is- the better method. All the poles 

 treated by this method exceeded the specification requirements for preservative pene- 

 tration and retention, 0.75 inch (1.9 cm) or 85 percent of the sapwood and 1 lb 

 (0.45 kg) of dry pentachlorophenol in the outer 0.5 inch (1.3 cm), respectively. None 

 of the poles treated by the cold soak method met the preservative retention requirement 

 and only the poles soaked for 9 and 6 hours met the preservative penetration requirement. 



PUBLICATIONS CITED 



American Wood Preservers' Association. 



1969. AWPA standards (loose leaf and currently revised). Am. Wood Preserv. Assoc., 

 Washington, D.C. 

 Lyon , L . J . 



1977. Attrition of lodgepole pine snags on the Sleeping Child bum, Montana. USDA 

 For. Serv. Res. Note INT-219, 4 p. Intermt. For. and Range Exp. Stn., Ogden, 

 Utah. 



Tegethoff, A. C. , T. E. Hinds, and W. E. Eslyn. 



1977. Beetle-killed lodgepole pines are suitable for powerpoles. For. Prod. J. 

 27(9):21-23. 

 U.S. Department of Agriculture. 



1974. Wood handbook - wood as an engineering material. USDA For. Serv. Wood Handb . 

 72. Washington, D.C. 



•if U.S. GOVERNMENT PRINTING OFFICE: 1 979 .0-677 • 1 2l/90 



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