Hemlock vs Spruce in Glacier Bay

Spruce tree on left, Hemlock tree on right of image.

NPS Photo

By now you may have noticed that Sitka spruce (Picea sitchensis) have singular dark green needles that are square and sharp to the touch. They have scaly bark that flakes off in small circular plates. Also present are western hemlock (Tsuga heterophylla) with blunt-tipped, soft, shiny, flat needles and stringy bark that becomes thick and furrowed with age. The relationship between these two trees and their presence in this forest is like that old story of the tortoise and the hare. Spruce grow quickly and need considerable sunshine. Hemlock grow slowly, but are shade tolerant. Though it seems like there are more spruce present right now, hemlocks might be slowly catching up and may eventually dominate. Time will tell.