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Sunday, November 29, 2015





Sunday,  9:30 AM.  30 degrees F at the ferry dock, 25 on the back porch.  The wind is variable and calm, the sky clear.  The humidity is 82%, the barometer 30.44" and beginning to fall.  Snow is predicted for late Monday through early Thursday, but today is beautiful.
   White spruce, Picea glauca, in the Pine Family (Pinaceae), is among the most cold tolerant of the conifers.   At the northern limits of tree growth, where the boreal forest meets  the tundra, it grows in association with black spruce, aspen, and paper birch.  It's natural distribution  includes most of Canada and Alaska, and around the shores of the Great Lakes.  It grows best in zones 3 and 4, but will grow further south when planted in the right conditions.  It becomes a large tree, growing to fifty or even a hundred feet in height in landscape situations and often taller in nature.
   I would describe it as similar to the ubiquitous Colorado blue spruce (Picea pungens) but less intense in every way; not as blue in needle color, the needles not as long nor as stiff, and the cones not as large.  Where it can be grown, it is now a better choice than the Colorado blue spruce, which is susceptible to a very disfiguring and often fatal fungal needle cast.  I think it also more subtle in the landscape; the Colorado blue spruce can appear very garish if improperly used.
   That said, the two spruces are closely related, the Colorado spruce being formerly named Picea glauca var. pungens.  
To add to the confusion, the Black Hills spruce of the nursery trade is actually considered a southern disjunct population of the white spruce populations of Canada to the north, left behind by the glaciers as they retreated. The latin species name glauca refers to the whitish bloom of the needles, and pungens to the odor of the Colorado blue spruce needles when crushed.

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