1048 JOURNAL or" FORESTRY 



and the date of germination that delayed germination in the conifers 

 of the Northwest is as follows : 



Years 



Douglas hr 6 



Noble fir 3 



Silver fir 5 



Western hemlock 6 



Western white pine 6 



Pacific yew 10 



Dwarf juniper 10 



The delayed germination, in the author's belief, explains the age 

 classes in the reproduction found in open burns where there are no 

 seed trees. 



Extensive tests on the artificial storage of seeds in the dufT under 

 the forest canopy have been undertaken with many western species. 

 Unfortunately these studies have not been carried sufficiently far to 

 determine the period of delayed germination for the several species. 

 The author states, however, that at the beginning of the second season 

 germination tests show some seeds of all the species stored still viable. 



The main conclusions drawn from the author's studies are : 



(i) The distance to which seed trees are capable of restocking the 

 groimd is limited to from 150 to 300 feet. They cannot, therefore, 

 account for the restocking of the large burned areas. 



(2) The irregular, dense stands of young growth are due to seed 

 stored in the forest floor or in cones. This seed retains its viability 

 through the fire and is responsibile for the dense reproduction that 

 s]:)rings up after the first fire. 



(3) The even-aged stands of reproduction immediately following a 

 fire, regardless of location of remaining seed trees, the irregular alterna- 

 tion of dense stands of reproduction with grass areas, and the failure 

 of reproduction on areas burned over by a second fire before the stand 

 reaches seedings age or by consuming all of the dufif and precluding 

 any possibility of seed remaining after the fire, all point to the seed 

 stored in the duff as the principal source of seed responsible for the 

 restocking. 



(4) The ability of the seed to retain its viability when stored in the 

 duff or when retained in cones during fires has been further demon- 

 strated by recovering and germinating seed from duff under forest 

 conditions and by recovering and germinating seed from cones which 

 passed through a crown fire. 



Hofmann's studies are of great interest and of much practical value. 

 They do not, however, completely solve the problem of how long the 

 seeds of the northwestern conifers remain viable in the ground in 



