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JOURNAL OF FORESTRY 



This would indicate that seedhngs from the Monterey seed showed 

 increasing immunity to loss with increasing age of seed while the 

 reverse is true for the Humboldt seed. 



These results are shown graphically in figure 3 in which the straight 

 line averages for both lots of seed were computed by the method of 

 least squares. The computation shows in the case of the Humboldt 

 seed an increase in loss of seedlings with increasing age of cones of 

 .82 of one per cent per year, while the Monterey seed shows a de- 

 crease in loss of 1.7 per cent per year. 



It is again difficult to see why such divergence should exist for 

 these two lots of seed. It is highly improbable that other lots of seed 

 would show the same differences but this again can only be deter- 

 mined by future extensive experiments. If such differences should 

 exist it would be advisable to collect cones of recent maturity from old 

 trees and older cones from less mature trees. 



Table 6. — Comparison of Germination of Bishop Pine Seed from Old Trees, 

 Humboldt County, and Young Trees, Monterey County. 



Total germination during 90 days. Average of 

 ages M to M -|- 6 



Total av. germ, for seed M + 7 to M -|- 13 years. 



Average survival at 120 days M to M + 6 



Average survival at 120 days M + 7 to M-|-13... 



Average loss of seedlings M to M + 6 



Average loss of seedlings M -)- 7 to M + 13 



Total : 



Germination of seed during 90 days. Average of 

 all ages M = M + 13 



Average survival at 120 days. All ages M to 

 M + 13 



Average loss of seedlings M to M + 13 



Table 6 gives a comparison of the general averages for all ages of 

 the two lots of seed from which it may be seen that the seed from 

 younger trees has a much higher germinative capacity and vitality. 

 The most interesting thing about this table is. however, the fact that 

 the older age classes of seed from the Humboldt trees show so much 

 higher germinative capacity and survival than the seed of the younger 

 age classes. 



