Germination of Forest Trees 



49 



conspicuously: Pinus ponderosa, Pinns jeffreyi, Pinns coulteri; 

 and Libocedrus decurrens. This table shows that the Pacific 

 coast species are predominantly moisture-loving. 



The foregoing table is a classification of all species used in the 

 soil moisture experiments upon the basis of whether they ger- 

 minated in all three soil moisture cultures, in two of them or in 

 only one of them. These three groups are called by the terms 

 xerophilous, xero-mesophilous, and mesophilous. Xerophilous 

 species are those that germinated in all three cultures; xero- 

 mesophilous species are those that germinated in the medium wet 

 and the wet soil cultures ; and mesophilous species are those that 

 germinated only in the wet soil culture. 



TABLE VII 



The Effect of Soil Texture on Germination 



Eastern Species 



Species 



Pinns strobus 



Pinns divaricata 



Pinus divaricata (F. S.) . 



Pinns resinosa 



Pinus palustris 



Pinus taeda 



Abies balsamea 



Catalpa speciosa 



Catalpa speciosa (Neb.) . 



Quercus rubra 



Robinia pseudacacia . . . 



Betula papyrifera 



Acer rubrutn 



Gleditschia triacanthos . . 



Loam 



c m 



caO rt 



22 

 12 

 14 



24 

 31 

 34 

 18 

 18 

 16 

 40 

 8 



34 



18 



o 





la 





c ' 



50 

 32 



20 



16 



53 

 6 



30 



i 



12 

 28 



16 



I 

 30 







10. 



54- 

 39- 

 30. 



10. 



io- 

 II. 



I. 

 91. 

 28. 

 28. 



i. 



17- 

 o. 



Sand 



a >> 



be rt 

 v 



23 



18 



12 



16 



20 

 26 

 28 



14 



o 



16 



38 



8 



34 

 24 



34 



a >* 



Cm 



34 

 38 



18 

 54 

 54 

 12 



34 



o 



12 



46 



18 



1 



18 



1 



. c 



1 V 



Ph 



I I 

 72 

 32 



85 

 12 



41 

 18 



o 

 92 

 24 

 39 



3 

 13 



1 



Gravel 



Q 

 P3 M 



34 

 10 



16 

 16 

 22 

 40 

 16 

 o 



16 

 30 



8 



34 



18 







~0 C/5 



o >^ 



38 



40 



18 



8 

 62 



1 

 40 



o 



1 



54 



18 



1 



8 



o 



go 



Ph 



7.0 



45-5 

 28.0 



16.5 

 9-5 

 1.0 

 7.0 

 0.0 

 9.0 

 16.0 

 11. 5 

 0.5 

 8.0 

 0.0 



Tables VII, VIII, and IX show the effect of soil texture upon 

 the same species. 



Table VII shows that for the 12 species considered in the final 

 results only one germinated first in the loam culture. Three 

 germinated simultaneously in all cultures, three first in the sand, 

 and four germinated first in the gravel. Three species had the 

 longest germination period in loam, two in sand and 5 in gravel. 



