Down by the bay…

Well, down by the side of the lake anyway.  No watermelons there (as in the song), but instead an unusual (deciduous) conifer that drops its needles in the winter.  It’s a Tamarack (Larix laricina), or Larch, as it is called up north.

Tamarack are nothing but bare scraggly branches and cones during the winter, having dropped their needles in the fall.

Tamarack are nothing but bare scraggly branches and cones during the winter, having dropped their needles in the fall.

tamarack cones

Pure stands of Tamarack Larch can be found throughout parts of Canada and extreme northern U.S.  The color change produces a glorious scene in the fall when the short needles turn bright yellow.

Flaming Larch trees in the Enchantments, Washington state.

Flaming Larch trees in the Enchantments, Washington state in October.  Photo from http://www.summitpost.org/

The tree is quite tolerant of a wide variety of environments, but favors wet swampy places.  It  can tolerate cold temperatures down to -60 F, making it one of the few trees to be found on the edge of the arctic or alpine tundra.

Like the Bald Cypress (also a deciduous conifer), Tamarack Larch have to make adjustments to keep their root tissue oxygenated in the stagnant swampy water.  Where Bald Cypress send up root knobs (knees) above ground, Tamarack Larch instead spread their root mass widely through a thin layer of topsoil.  However, one problem with this solution is that without a deep taproot anchor, they become vulnerable to damage from high winds.

This side view of a downed tamarack shows how shallow the root ball can be in a particularly swampy area.

This side view of a downed tamarack shows how shallow the root ball can be in a particularly wet, swampy area.

The wood is tough and durable, but flexible.  Algonquian Indians made their snowshoes from larch strips.  Log roads over swampy areas and corner posts marking property were often constructed from tamarack because of its high resistance to rot.

It’s curious why so few conifers are deciduous (in fact, most of the examples are species of Larch), even though you might think it would be more advantageous to lose needles in the winter when the tree can’t use them for photosynthesis anyway.  Bare branches can also shed snow more easily, and are less likely to break under the weight of a snow pack, as well.   Perhaps the answer lies in where these species grow best.

Most evergreen conifers are adapted to dry, cold climates, where decomposition is very slow and the nutrients necessary for production of new needles every year are in short supply.  In that case, it makes sense to hang on to the needles and replace them slowly over several growing seasons, as nutrients become available.

On the other hand, swamps are nutrient-rich places full of lots of decomposition products, and Larch species have specialized on this rapid turnover, allowing them to rebuild a crop of needles each growing season.

Ah, the myriad ways of nature…

5 thoughts on “Down by the bay…

  1. Larch is one of my favorite trees and some varieties are used in landscaping. Unfortunately they are also a messy tree and drop many small limbs that have to be constantly picked up. I call them “self pruning” trees, much like a weeping willow.

    • This was a new tree for me, despite having seen it for years and never really paying attention to its biology — which I now find fascinating. Larch are tolerant of many conditions, except lack of light, self pruning being a consequence of the non-productivity of shaded lower branches as the tree grows. Who knew trees were so smart!

Please Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.