By Sheryl Normandeau

This past September, my husband and I finally had a chance to hike into the famed Larch Valley, near Lake Louise, Alberta.  I use the word “famed,” but perhaps that should read “notorious,” instead:  during the very brief period when the autumn colours of the larch trees above Moraine Lake are at their peak, the crowds of visitors become so massive that traffic jams ensue and police supervision is required!   It’s not difficult to understand why people get so worked up about a bunch of trees, however, when you consider spectacular views such as this:

Alpine larch trees in Larch Valley, Lake Louise, Alberta

Larch (Larix spp.) trees have always been special favourites of mine – I think it’s that whole deciduous-conifer thing.  I’ve always been fascinated by the fact that larch trees, members of the pine family (Pinaceae), have soft green needles that turn brilliant yellow in autumn and then drop.  A conifer that is not evergreen – how novel is that?  There aren’t very many other trees that can make the same claim, although you can add dawn redwood (Metasequoia glytostroboides) and bald cypress (Taxodium distichum) to the short list.

There are several types of larch trees that are native to North America.  Larix lyalli, or alpine larch, are the beauties we saw in the Valley.  Alpine larches are perfectly suited to their cold, snowy environment.  Fine woolly hair shelters buds and twigs from harsh weather, and trees thrive in dry, gravelly soils.  As we noticed on our hike, alpine larches are usually found in pure stands, at high elevations, where they help control slope erosion.

I’m originally from northern Alberta, where Larix laricina (tamarack, also known as hackmatack or American larch) are common.  Tamaracks are found in poorly drained, boggy soils, usually in stands accompanying black spruce (Picea mariana).

Western larch (Larix occidentalis) can top out at a whopping 40 metres tall.  (Compare that to tamaracks and alpine larches, which usually grow to 15 metres).  Western larches are a pioneer species often found in areas that have been ravaged by a forest fire.

Introduced larch species include Larix siberica, a native of eastern Russia, Siberia, and northern China.  This long-lived (up to a century is not uncommon), drought-tolerant tree is sometimes used in shelterbelts.

Japanese larch, Larix kaempferi (syn. Larix leptolepis) thrives in well-drained soils at high altitudes.  It is occasionally kept as bonsai, and is often used as a garden ornamental.

Another Russian/Chinese native, Larix gmelinii (Dahurian or Kurile larch) grows equally well in saturated or well-drained soils.  It is very cold hardy and actually struggles to grow in areas with mild winters.

A common ornamental, Larix decidua or European larch, is an introduced species that has naturalized throughout North America.  The needles of European larch are longer and denser than other species, and the branchlets characteristically droop slightly downwards.   Cultivar ‘Pendula’ is a popular tree sold at garden centres – a compact height of 3.5 metres and very prominent weeping habit make it a fantastic accent plant in the landscape.

Flowers of European larch (females are pink, males are yellowish)

Did you know…?

  • The word tamarack derives from the Algonquin word akemantak, which means “wood for snowshoes.”
  • Dahurian larches can actually grow in the poor topsoils above permafrost.
  • Weeping larches (Larix decidua ‘Pendula’) are highly bothered by pollution.  Don’t plant them near busy city streets.
  • The alpine larches in Manning Park, near Vancouver, British Columbia, may be among the oldest living trees in Canada.  It is speculated that they may be over 1,900 years old!  Some alpine larches in the Kananaskis region of southern Alberta are likely five centuries old.
  • Western larches have very thick, fire resistant bark.  Mature trees also shed their lower branches to keep from catching fire.
  • If you’re stranded in the mountains and desperate for food, you can make a (presumably not terribly tasty) soup from young alpine larch twigs.

For more information:

http://www.for.gov.bc.ca/hfd/library/documents/treebook/trees.htm  This is a great resource from the Government of British Columbia’s Ministry of Forests, Lands and Natural Resource Operations – it lists all of the species of trees found in the province, including several types of larches.  Detailed information about each tree is included.

http://www.abtreegene.com/trees.html – The Alberta Forest Genetic Research Council’s site contains some excellent information about tamaracks and alpine larches.

Sheryl Normandeau is a writer and gardener from Calgary, Alberta.  She blogs at Flowery Prose.