38 



H. B. HUMPHREY AND J. E. WEAVER 



About 26 years ago many square miles of these hills were 

 overrun by a fire which destroyed more or less completely much 

 of the virgin timber, leaving here and there a few living trees rep- 

 resenting the different species to serve as seed trees in subse- 





Fig. 5. A virgin forest of white fir, tamarack and cedar. Characteristic 

 plants are Acer glabrum var. douglasii, Lonicera ulahensis, Vaccinium membran- 

 aceum, Ribes lacusire, Thaliclrum occidenlale, and Disporum spp., under which is 

 a carpet of Smilicina sessili folia, Coptis occidentalis, Asarum caudatum, and Clin- 

 lonia uniflora. Thatuna Hills, Idaho. 



quent years. These burns covered chiefly the north and north- 

 east slopes of the mountains. In these mixed forests of white 



