western wliite pine, and western hemlock predominate. 

 The growth at these elevations is slow, the trees are 

 small, and due to their inaccessibility, are not con- 

 sidered as being merchantable. 



Because the pine and fir forests are of such ex- 

 tent and value, and because they are the greatest source 

 of limber within the state, most of this study of Light 

 Burning has to do with the conditions found and the 

 practice followed therein. The species represented here 

 are predominantly sugar pine, yellow pine, incense cedar 

 douglas fir, white fhr and red fir, of which species 

 the sugar pine and yellow pine are of the most value. 

 These species do not all occur in the same uniformity 

 thruout the stands, however, due to the fact that their 

 requirements of site are not similar. Thus, the trees 

 grow in more or less distinct groupings or types de- 

 pendent upon the conditions of site as meeting the re- 

 quirements of the several species. The types commonly 

 irecDgni^ied are yellow pine, sugar pine - yellow pine, 

 sugar pine - fir, and fir, the predominant spedies in 

 every case denoting the type. 



In general, it may be said that the yellow pine 

 and the sugar pine - yellow pine types are on plateaus 

 and southern exposures at moderate elevations (5000') 

 while the sugar pine - fir type prevails on northern 

 exposures between 5000'-6000'. Pir types are on the 

 higher elevations above the point where the sugar pine « 

 fir type ceases to exist, they in turn being bounded 



