The North American and Western Larch

Eastern larch cones
Tamarack larch foliage and cones in August. The lighter brown cones are from the current season; the darker brown cones are mature cones from previous seasons.

Tim and Selena Middleton/Wikimedia Commons/CC BY 2.0

The native range of the Tamarack, or Larix laricina, occupies the coldest regions of Canada and the northern-most forests of central and northeastern United States. This conifer was named tamarack by native American Algonquians and means "wood used for snowshoes" but has also been called eastern tamarack, American tamarack, and hackmatack. It has one of the widest ranges of all North American conifers.

Although thought to be a cold-loving species, tamarack grows under extremely varied climatic conditions. It can be found in isolated pockets in West Virginia and Maryland and in disjunct areas of interior Alaska and the Yukon. It can easily survive average January cold temperatures from -65 degrees F to warm July temperatures that exceed 70 degrees F. This toleration of climate extremes explains its wide distribution. The extreme cold of northernmost strands will affect its size where it will remain a small tree, attaining a height of about 15 feet.

Larix laricina, in the pine family Pinaceae, is a small to medium-size boreal conifer that is uniquely deciduous where needles annually turn a beautiful yellow color and drop in autumn. The tree can grow to 60 feet in height on certain sites with trunk growth that can exceed 20 inches in diameter. Tamarack can tolerate a wide range of soil conditions but grows most commonly, and to its maximum potential, on wet to moist organic soils of sphagnum and woody peat.

Larix laricina is very intolerant of shade but is an early pioneer tree species that invades bare wet organic soils by seeding. The tree typically appears first in swamps, bogs, and muskeg where they start the long process of forest succession

According to one U.S Forest Service report, "the principal commercial use of tamarack in the United States is for making pulp products, especially the transparent paper in window envelopes. Because of its rot resistance, tamarack is also used for posts, poles, mine timbers, and railroad ties."

The key characteristics used for the identification of tamarack:

  • This is the only eastern conifer with deciduous needles arranged in radiating clusters.
  • Needles are growing from blunt spurs in groups of 10 to 20.
  • Cones are small and egg-shaped with no visible bracts between scales.
  • Foliage turns yellow in autumn.

The Western Larch or Larix occidentalis

Western larch or Larix occidentalis is in the pine family Pinaceae and often called western tamarack. It is the largest of the larches and most important timber species of the genus Larix. Other common names include hackmatack, mountain larch, and Montana larch. This conifer, when compared to Larix laricina, has a range that is much reduced to just four U.S. states and one Canadian province—Montana, Idaho, Washington, Oregon, and British Columbia.

Like the tamarack, western larch is a deciduous conifer whose needles turn yellow and drop in autumn. Unlike tamarack, western larch is very tall, being the largest of all the larches and reaching heights of over 200 feet on preferred soils. The habitat for Larix occidentalis is on mountain slopes and in valleys and can grow on swampy ground. It is often seen growing with Douglas-fir and ponderosa pine.

The tree does not do as well as tamarack when dealing with broad changes in climatic factors as a species. The tree grows in a relatively moist-cool climatic zone, with low temperature limiting its upper elevational range and deficient moistures its lower extremes—it is basically limited to the Pacific northwest and to the states mentioned.

Western larch forests are enjoyed for their multiple resource values including timber production and aesthetic beauty. The seasonal change in hue of larch's delicate foliage from light green in the spring and summer, to gold in the fall, enhances the beauty of these mountain forests. These forests provide the ecological niches needed for a wide variety of birds and animals. Hole-nesting birds comprise about one-fourth of the bird species in these forests.

According to a U.S Forest Service report, western larch timber "is used extensively for lumber, fine veneer, long-straight utility poles, railroad ties, mine timbers, and pulpwood." "It is also valued for its high water-yielding forest-areas where management can influence water yield through harvest cuttings and young stand culture."

The key characteristics used for the identification of western larch:

  • A larch tree's color stands out in forests—pale grass green in summer, yellow in the fall.
  • Needles grow from blunt spurs in groups like L. laricina but on hairless twigs.
  • Cones are larger than L. laricina with visible yellowish, pointed bracts between scales.