SEED CHARACTERISTICS IN CONIFEROUS FORESTS 



13 



The sowing failed on the south slope. A few seeds germinated, but the 

 seedlings perished during the dry season. The noble fir did remarkably 

 well on the north slope, and the Douglas fir and white pine did fairly well, 

 but the yellow pine failed. There was no loss of the total number germi- 

 nated. 



On the flat the Douglas fir did very well and had a 15 per cent loss of 

 the total germination. The noble fir did fairly well, with a loss of 30 per 

 cent of the total germination. The white pine germinated very little and 

 had a loss of 46 per cent of total germination, while the yellow pine germi- 

 nated very little, and 15 per cent of the total germination died. 



The conditions under which the seedlings become established are shown 

 in the following average summary of four areas studied in northern Idaho. 



TABLE III 



CONDITIONS UNDER WHICH SEEDLINGS WERE FOUND ESTABLISHED 

 IN NORTHERN IDAHO 



In regard to the areas examined, the above tabulation shows that the 

 white pine seedlings start about equally well on the duff, wood litter, and 

 mineral soil, while the other species do not show any particular preference. 

 In this study, moisture was found to be the controlling factor, and the 

 other conditions recorded are usually favorable only where they produced 

 better moisture conditions. 



Effect of ground cover after burns or cuttings. An area was selected on 

 a south slope at an elevation of 1,700 feet, where the ground cover of wild 

 pea vine and brush was very dense. One square rod was denuded of all 

 vegetation and the area beside it left untouched. Readings of air temper- 

 ature at the height of the crowns of seedlings, and soil temperature at 

 surface, 6 inches deep, and 12 inches deep were taken each week on the 

 denuded area and in the adjoining -area where the natural vegetable cover 



