mertensiana – refers to Karl Heinrich Mertens, a German botanist who identified species in 1827

Native range: Alaska to California

Leaves:

• linear leaves
• leaves spirally arranged (looks like a bottle brush)
• arranged like points of a “star” at branch end
• needles all similar length 1/4–3/4” long
• bluish-green
• stomata on both sides
• base attached to stem via a short peg and short petiole (stalk)

Cones:

• large (2–3” [3–8 cm] long) compared to other Tsuga (w/ small 1/2–1” long cone)
• male cones – bluish
• female cones – light to brownish purple, becoming brown at maturity

Other characteristics:

• evergreen tree to 130 ft.
• slow-growing
• bark dark reddish-brown and furrowed
• top of tree drooping

Relevant info:

• may reach 800 yrs old
• as an ornamental, adaptable to a wide variety of climatic conditions

Ecology & Adaptations:

• native to Alaska to California, east to Montana
• in both Olympics and Cascades in Washington
• found in coastal and montane forests to alpine slopes (where it occurs in krummholz (German for ‘crooked wood’) form, i.e., stunted due to continual exposure to fierce, freezing winds)
• 0–2400 m. (mostly at high altitudes but elevational range of the species varies with latitude)
• subalpine or montane species associated with long winters and deep snowpacks
• often occurs up to timberline and in subalpine parkland (mosaic of meadow and tree clumps)
• north of Vancouver Island, associated with bogs and wet sites with deep organic soils, sometimes at low elevations
• sexual reproduction – 2-year reproductive cycle:
  • cones produced in first year
  • pollination occurs in spring or early summer of the second year
• pollinated by wind
• seed dispersal – winged seeds are dispersed primarily by wind
• vegetative reproduction via layering
  • effective means of regenerating at timberline, since layered saplings are sheltered by the growth of the parent tree and initially receive their nutrients through the established root system of the old tree
  • also important in stressful conditions of muskegs (wetlands) of Alaska
• regeneration in subalpine parkland:
  • cluster of trees contains at least one tree tall enough to project above the winter snowpack
  • dark-body radiation emitted from the tree causes the snow to melt sooner and faster near the tree than in the open meadow, reducing snow accumulation and producing conditions conducive to both the growth of existing trees and the establishment of new trees, both from seed and via asexual means (layering)
• adaptation to deep snow in subalpine – soil usually does not freeze in these forests, and this species can grow at near-freezing temperatures if its roots are not frozen
• wind-adapted – growth as low-spreading shrub or small tree limits exposure