In a previous article, the difference between conifers and evergreens was discussed. In that article, a specific tree was mentioned; Western Larch, also known as Tamarack. Larch trees are unusual among conifers in that although they are true conifers, they aren’t evergreens, they are deciduous. It might be interesting to get a better idea of what a larch tree is and looks like.
In northwestern Montana, there are a large number of larch trees and in the fall, they lend gold and yellow colors to the forests. It is a beautiful contrast to the deep green of firs and pines.
The color change happens when the tree withdraws the green-pigmented chlorophyll from the needles in preparation for the winter. As with other deciduous trees, once the chlorophyll is withdrawn, all the leaves, in this case needle-shaped, fall to the forest floor. This is unique among the conifers. Other conifers retain their needles through the winter. A few needles do fall here and there throughout the year, but it isn’t all at once on most conifers and they are replaced throughout the year, too, so other conifers never appear “naked” unless they are dead.
The yellow-gold color in this image is from larches that have turned color in the autumn. The problem with this image is that since it was taken from our back porch and is of a hillside to our south, it is 3-4 miles away. Although the color contrast between the yellow of the larches and the dark green of the firs and pines is clear, at the distance that is involved, it is hard to make out the larches clearly. Certainly, not much information can be gleaned about larches at this distance, except that they change color.
This isn't much because many people wouldn't be able to identify a larch in the summer when it was dark green like the other conifers. Yet, it isn't at all difficult to identify a larch tree.
This picture is closer up, showing the beautiful color of larches against the green of white fir trees. The mountain goat appears healthy and at home in this forest, which is sure to be the case.
You might notice that the general shape of the golden yellow larches is very much like the dark green white firs. That isn't surprising since the trees are closely related, but it should give a person the idea of why it wouldn't be easy to tell which trees were larches and which were firs, even at this distance, if they were all the same shade of green, which does happen in the summer.
This is what a larch forest looks like in the winter, with the trees bare of their needles. At first glance, these larches appear dead. They aren't, though. They are merely dormant. In the spring, these trees will put out new needles and this forest will look lush again.
At first, the needles of new growth in the spring are light lime-green. It takes several weeks for the needles to grow to full size and to darken to the shade of dark green that firs and pines are known for.
Both larches and firs are members of the pine family, though neither looks like a pine tree, up close. In the firs, the needles are attached directly to the branches, along its length. People who've used real fir trees as Christmas trees have a good idea of how the needles are arranged on a fir branch.
A larch is different in that the short needles are arranged in whorls, as can be seen in this image. Among other things, this is a time-saver for the trees. When they drop their needles in the fall, they actually drop the whorls of needles, rather than needing to drop each individual needle. It can take as little as a few days to a week for an entire larch forest to go from golden-yellow to barren.
This is important in the mountains, where winter-weather can strike abruptly and remain both snowy and cold for months, until springtime.
One of the things that all conifers have in common is that the seeds are produced in cones. This is a comparison of the cones of a larch tree (Larix laricina) on the left and Douglas fir (Pseudotsuga menziesii) tree cones on the right. As can be seen, the cones are very similar.
The cones are one of the means of positively identifying the tree. For example, look closely at the cones of the Douglas fir. While Douglas firs aren't true firs (implied by the "Pseudo..." part of the genus name), each of the cone scales has a bract that looks rather like the tail and rear legs of a squirrel jumping down a hole. This is distinctive and no other fir or pine has cones that look this way.
Although the larch doesn't have those bracts, there is also no other fir or pine tree that has cones that look exactly like those of the larch.
This image also shows how the needles are arranged on the branches of fir trees, which makes it much easier to tell the difference between them and the larches, which has whorls of needles.
Larch is one of the most commercially important wood trees, especially in the west. The wood grain is quite beautiful and this wood has been used extensively for house construction, flooring, plywood, particleboard, and paper. It is also used for fencing, as shown in this picture. The wood in the picture has been allowed to become weathered and seasoned. Often, it is stained instead, but the grain is so beautiful that painting isn't commonly done to the wood.
People who read the article about the major project that was finished, putting in a storage shed, might recognize that in the first picture of that set, the fence that was shown was made of the same wood as what is shown in this picture, although it isn't the same fence. Our side fence is made of larch.
Larch is also an important type of firewood and the major fire we had locally two years ago burned a large amount of larch forest. Three of the four cords of wood that our neighbor has cut, split, and stacked so far for firewood is larch that came from the cleanup in the area of the fire.