THE EOTS OF WESTERN WHITE PINE. 



In order to get a first-hand impression of the characteristics of 

 western white pine from the point of view of the logger, question- 

 naires were sent to a large nmnber of lumber and logging concerns 

 operating in the Northwestern States. Out of the total answers re- 

 ceived 18 were selected in which the replies to the questions were 

 complete. Most of these answers were received from companies oper- 

 ating in the States of Oregon, Washington, Idaho, and Montana. 



In respect to site, most of these answers state that the rot is 

 greatest in trees occurring on fiat, low, and poorly drained land, and 

 that the best sites, where trees are freer from rot, are well-drained 

 slopes or benches. Altitudes ranging from 1,500 to 7,500 feet are 

 given as most favorable to healthy stands, and conversely the greatest 

 proportion of rot is found in stands at altitudes below 1,500 feet. 



In Table I it is seen that the proportion of rot on the bottom sites 

 (7.8 per cent) is somewhat greater than on the slope sites (6.1 per 

 cent). Apparently, this difference is directly due to the site and 

 corroborates what has already been said in reference to environment 

 favorable to fungous development. The above comparison of rot 

 percentages ior the two types of site is made more exclusive when 

 the figures for the percentage of infected trees for each type are 

 considered. The difference, presumably, would have been still 

 greater if the proportion of the trees on sites of the slope type in 

 certain of the older age classes had not been so much greater than 

 for sites of the bottom type. In Table II a comparison is made be- 

 tween two sale areas in the same forest but separated by a consider- 

 able distance. The trees occurring on the slope sites only were used, 

 and these were restricted to the age class of 121 to 160 years. A 

 glance at Table II will show that the trees from the Honeysuckle 

 sale area averaged 132 years and those of the Silver Creek sale area 

 142 years, a difference of 10 years. 



Table II. — Comparison of tioo sale areas of western white pine of the 121 to 

 160 age class grovnng on slope sites, showing the relation of rots to site. 



[T. R.=tnmk:-rot, B. R.= butt-rot.] 





Average 



age 

 (years). 



Total volume (cubic feet). 



Volume of rot 

 (percent). 



Number of trees (basis). 



Sale area. 



Stand. 



Rot. 



T.R. 



B.R. 



T.R. 



Total. 



Sound. 



Infected. 





T. R. 



B.R. 



T.R. 



+ 

 B.R, 



T.R. 



+ 

 B. R. 



Per- 

 cent- 

 age. 



Honeysuckle. 

 Silver Creek. 



132 

 142 



22,172 

 18,095 



323.5 

 536.6 



96.1 

 1.6 



419.5 

 538. 3 



1.45 

 2.96 



0.43 

 .01 



1.89 

 2.97 



122 

 106 



36 



24 



86 

 82 



70.5 

 77.3 



128265°— 19— Bull. 799- 



