LODGEPOLE PINE 



The soil moisture stress levels applied in the test had no influ- 

 ence on lodgepole pine stock (fig. 3). Survival averaged 90 per- 

 cent at all three stress levels. Obviously, the test procedures failed 

 to create a sufficient range of moisture stress to adequately test 

 this species. This survival tenacity of lodgepole pine under mois- 

 ture stress conditions that were so devastating to spruce and larch 

 stock was rather surprising. Previous testing of ponderosa pine, 

 considered the most drought tolerant of species raised at the 



Coeur d' Alene Nursery, has resulted in very low survival rates at 

 high stress levels (Boyd and others 1972). 



Both storage regime and planting date had a highly significant 

 effect on pine survival at all stress levels (table 4). Until the 

 June 27 planting, survival was excellent at all stress levels and 

 storage regimes. Stock stored in regular nursery storage virtually 

 failed when planted in late June. Stock stored in the snow cache 

 survived significantly better, but still compared poorly to frozen 

 and fresh stock. 



100 i- 



P 60 



20 



100 r- 



Extreme Stress 

 (average 89 %) 



Reg. (82) 



60 



40 



20 



All Stress Levels 

 (average 90%) 



Frozen (73) 



> \ Fresh (95) 

 \ \ 



\\ 



\ \ Snow (90) 



\ 

 \ 

 \ 

 \ 

 \ 

 \, 



Reg. (81) 



4/4 



4/25 5/16 



6/6 



6/27 



4/4 



4/25 5/16 



6/6 



__L 



6/27 



PLANTING DATE PLANTING DATE 



Figure 3.— First-season survival of lodgepole pine planting stock under four storage regimes, 

 planted throughout the spring season. Figures in parentheses are average survivals over all planting 

 dates. Significance differences attributable to storage are shown by * and ** (p = 0.05 and 0.01, re- 

 spectively) and connecting arrows. 



4 



