BOTANICAL GAZETTE [DECEMBER 
| Alnus incana 
Ulmus americana 
Picea mariana 
Larix americana 
| Fagus americana 
Tsuga canadensis 
Abies balsamea 
Betula papyrifera 
Pinus Strobus 
Populus tremuloides 
| Pinus Banksiana 
Fic. 4.—Fo: ‘ i 
4 rest trees: specific ranges of tolerance with respect to water 
