168 Postelsia 
the shores of the Gulf of Alaska to northern 
California. 
This spruce is the most characteristic tree of 
the Pacific coast forest, growing throughout 
almost the entire length of the region, but never 
occurring far from the ocean. It cannot endure 
extremes of summer heat or winter cold, but 
under the pecular conditions which obtain along 
the Alaska coast, it reaches the extreme limit of 
tree growth in that direction. It forms one of 
the largest trees in the forests of western Van- 
couver Island. Specimens sixty meters high, 
with trunks two meters in diameter are not rare 
and not infrequently these dimensions are con- 
siderably exceeded. Under adverse circum- 
stances it can, however, maintain life for a long 
time with very little increase in size, and curious- 
ly dwarfed specimens have been found growing 
in crevices in the rocks of the upper beach near 
the Minnesota Seaside Station.* In one case a 
tree less than a foot in height was found to have 
an age of ninety-eight years. The western hem- 
* MacMillan, C. Note on some British Columbia Dwarf trees. 
Bot. Gaz. 38:379. 1904. 
