INTRODUCTION 



Three separate but related studies established in northern Idaho in 1935 provide 

 information on the response of representative young stands to release from overstory 

 shade and to lower densities achieved by cleaning. The parent timber type in each case 

 was western white pine (Pinus montioola Dougl . ) ; ecologically, the sites were classified 

 as Tsuga hetevo-phylla/Paahistima myrsinites habitat type (Daubenmire and Daubenmire 

 1968) . Some early results of cleaning operations on two of the study areas were de- 

 scribed by Wellner (1940, 1946). Boyd (1959) later reported on conditions and outlook 

 on these same areas 20 years after treatments. Ten more years of record, plus results 

 from a third set of plots, now give additional data on growth and dominance trends. 



The treatments used were designed to favor western white pine because of its para- 

 mount importance to the timber industries at that time. Current management programs 

 in the Northern Rocky Mountain region have deemphasized white pine production because 

 of the problems encountered in attempting to control losses from blister rust (Ketcham 

 and others 1968). Although the prospective role of natural white pine in this region 

 remains uncertain, progress toward producing genetically rust-resistant trees for 

 planting indicates there will be a continuing use for information on the responses of 

 western white pine to management practices. In addition, the records from these early 

 studies can help managers formulate guidelines for mixed-species management on 

 similar sites. 



^These studies were planned and installed by Carl E. Ostrom, Hans Roffler, George 

 M. Fisher, and Kenneth P. Davis; data on file at Intermountain Forest and Range Exp. 

 Station, Forestry Sciences Laboratory, Moscow, Idaho. 



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