The statistical analysis for the field seedbed experiment included the one-way 

 analysis of variance and the Newman-Keuls test for multiple comparisons. Statistics 

 were not needed in the laboratory seedbed test because of similarity of results. 



Results and Discussion 



In the field seedbed experiment, germination was fairly high in most treatments, 

 ranging from 62.5 percent to 91.3 percent. Seeds overwintering on the opening topsoil, 

 the canopy topsoil (opening) and the duff seedbeds had significantly better germination 

 than the seeds on the opening subsoil, litter, litter and duff, and canopy topsoil 

 (canopy) . The germination of the seeds from the canopy topsoil (canopy) was signifi- 

 cantly lower than for seeds on all other seedbeds as shown in the following tabulation: 



Seedbed Fevoent^ 



Opening topsoil 



91 . 



.3 



a 



Canopy topsoil (open) 



91, 



.3 



a 



Duff 



88. 



.8 



a 



Litter and duff 



80. 



,0 



b 



Litter 



78. 



.8 



b 



Opening subsoil 



77. 



.5 



b 



Canopy topsoil (canopy) 



62, 



.5 



c 



Periodic observations in late winter and early spring revealed that soils under 

 the pine canopies accumulated less snow than in the openings, and the canopy soils were 

 the first to lose their snow cover in the spring. The viability of the seeds from the 

 canopy could be reduced by exposure to cold and dry conditions after the snow melts, 

 causing lower germination. A phytotoxin could have also been responsible for the re- 

 duced germination in the canopy topsoil (canopy) seedbed. If so, the movement of the 

 canopy topsoil to the opening eliminated its effect, possibly due to increased moisture. 

 Also, both moisture stress and phytotoxins may have been acting simultaneously. 



The poorest germination of seeds overwintering in the open occurred from beds of 

 litter, litter and duff, and opening subsoil. It is very unlikely that opening subsoil 

 contains phytotoxins; physical soil properties may have been responsible. The germina- 

 tion of seeds from litter, and litter and duff seedbeds was reduced, but it was not a 

 drastic reduction. Phytotoxins may have been responsible, although opening subsoil 

 seeds were not influenced by phytotoxins and their germination was reduced. Thus other 

 environmental factors such as those in the subsoil seedbeds could have reduced germina- 

 tion in the duff, and litter and duff seedbeds as well. 



This experiment demonstrates that pine seeds overwintering on a topsoil seedbed in 

 the open, away from the influence of the pine canopy, have the greatest potential for 

 germination at the end of winter. 



In the laboratory seedbed experiment, the results of the duplicate samples--one 

 assayed after transferring the petri dish to the growth chamber and the other assayed 

 by first counting the number of seeds that germinated during the experiment and trans- 

 ferring subsamples of the ungerminated population to the growth chamber--were very 

 similar, so they were averaged. In the design of this experiment, fungal growth was 

 not expected to occur in seedbeds that had been autoclaved and the seedcoats treated 

 with fungicide; however, these samples did become contaminated. Seedbeds composed of 



Numbers followed by different letters are significantly different at the 5 percent 

 level . 



17 



