7 6 



Richard H. Bocrkcr 



the effect of size upon germination per cent, for many varieties 

 of the same species. This study would also bring out some 

 interesting relations between these varieties, as for example, cor- 

 relating the size and weight of the seed with the site upon which 

 the trees grew. 



The largest and the smallest seeds were separated from the 

 stock seed and counted, weighed, planted and carefully labelled. 

 Of each variety of Pinus ponderosa 500 seeds were used except 

 in the case of the California varieties. Due to the scant supply 

 of these only 200 seeds of each of these were used. In the case 

 of the Pseudotsuga taxifolia 200 seeds of each variety were used. 

 After germination began counts were taken every other day. 

 The tables below give the size of the seeds, weight of 500 seeds, 

 the number of seeds per pound, the final germination per cent., and 



Size and Weight of Seed in Relation to Germination Per Cent. 



Pinus ponderosa 



Pseudotsuga taxifolia 



Caribou, N. F., Idaho. . . 



Pecos, N. F., N. M 



Washington 



Colorado 



Madison, N. F., Mon. . . 



10. o 



4.0 



-0.5 

 9.0 



6.5 



