Plant Data Sheet















Mountain Hemlock, Tsuga mertensiana


From Sequoia National Park in California to Look Inlet in Alaska

Climate, elevation

Sub Alpine. Temp Range 20-38C

Local occurrence

Along the Crest of the Cascades.

Habitat preferences

Loose coarse textured, well-drained acidic soils.

Plant strategy type/successional stage.

Tolerates sites with long lasting snow pack. Not drought/shade tolerant. Minor climax species.

Associated species

 Abies amabilis, Chaecyparis nootkatensis, Vaccinium membranaceum, Abies Lasiocarpa, Picea engelmanii, Pinus contorta

May be collected as:


Collection restrictions or guidelines

Seeds shed in Late November and December.

Seed germination

Cold stratification of mature seeds shortens incubation time and may substantially increase germination.

Seed life

Seed viability ranges from 36-76% over a 2 yr period.

Recommended seed storage conditions

 In a cooler (cold stratification).

Propagation recommendations

Easily propagated by seeds and cuttings

Soil or medium requirements

Snow, mineral soil

Installation form


Recommended planting density

 2-3 m apart

Care requirements after installed 

Water weekly, then no water after 2 months.

Normal rate of growth or spread; lifespan

Very slow growing. 7-28m tall at 100 yrs. Life span 800+ yrs.

Sources cited


MacKinnon, Andy; Pojar, Jim. Plants of the Pacific Northwest Coast:Washington, Oregon, British Columbia and Alaska. Lone Pine Publishing. 1994.


 Silvics of NA, VI Conifers. Burns, Russel M. & Honkala, Barbara H. Technical Coordinators. FS. USDA.WADC. Dec 1990.



Data compiled by

Christer Lundstrom June 12, 2003