American Larch: New Hampshire’s Big Tree for February 2008
Although a major tree of the northern boreal coniferous forest of North America, there are no recent measurements of American larch (Larix laricina), also called tamarack and hackmatack, in the New Hampshire Big Tree records.
It grows naturally in northern New Hampshire, and in scattered boggy locations in southern New Hampshire. This lapse may be because larch is somewhat uncommon and unknown, or that it grows in boggy, wet sites where it’s difficult to measure.
Larch is easy to identify in both winter and summer. It is the only deciduous conifer tree in New Hampshire. In the fall, its needles turn a striking yellow color before they fall, leaving a very twiggy, dead -looking tree silhouette for the winter; usually a straight trunk with upward pointing branches at the top and horizontal branches lower. Small cones (one half to three-quarter inches) that look like little knobs or galls are attached along the top side of branches providing another distinctive winter identification clue – the only tree with cones but no needles. The old, oval cones can remain on the branches for years after releasing their seeds.
Its leaves are needles, so it’s classified in the pinaceae family of trees, even though it sheds them in the fall and is obviously not an evergreen tree. This unique adaptation means it can survive bitter cold and grow further north than any other tree. It’s totally dormant during the winter and doesn’t have the problem of protecting needles from the ravages of weather. Its range extends to northern Canada up to the Arctic Circle where temperatures can dip to minus 65!
On the southern edge of its natural range, as explained by William Cullina of the New England Wildflower Society in his book Native Trees Shrubs and Vines, “tamarack is relegated to floating bogs where constant evaporation keeps the substrate cool, and extreme acidity limits competition. It is a strange thing to walk out gingerly on a floating mat of sphagnum moss and see larch trees swaying back and forth on the rippling waves created by your footsteps in the water hidden below.”
It’s the first tree species to invade bogs where the seeds germinate in the sphagnum moss. Its roots eventually drop down through the bog to get to the firm bottom. Although restricted to walking on the board walks and not on the quivering moss, one can see small larch trees growing in this manner at the NH Audubon’s Ponemah Bog in Amherst, NH.
Another adaptation of larch trees that helps them grow in bogs or anaerobic sites with little oxygen in the soil, are altered internal chemical properties. From the US Army Corps of Engineers Wetlands Delineation Manual, Appendix Cl: ‘Species that produce high levels of nitrate reductase (e.g. Larix laricina) are adapted for life in anaerobic soil conditions.’
In spring, its new needles transform it from winter ugly to spring beauty. The tufts of light green, inch-long needles create a soft, lacy look for the summer. The tree’s regular pyramidal shape and light green color are attractive attributes – it grows to 40-80 feet and its slender trunk grows to about one to two feet in diameter, with scaly, reddish-brown bark.
The oval, winged seeds produced in cones about every four to six years are disbursed by the wind in the fall. Mice and voles gobble them up. Any seeds remaining go through the natural winter dormancy process, and the viable seeds will sprout in the spring.
Larch seeds don’t remain viable for much more that a year in the wild. They will only germinate when they encounter very specific conditions like consistently wet sphagnum moss. This is called its germination niche. Tom Wessels in his fascinating book Reading the Forested Landscape cites the larch to explain this idea. Once a larch germinates it can be transplanted and grow in conditions outside its germination niche. “A tamarack can’t germinate in a well-maintained lawn, but a young sapling can be successfully transplanted on one, so that all the tamaracks we see in parks and yards are transplants.” One larch tree doesn’t indicate its niche; look for groups of trees to show its natural growing habitat.
Not only are larch seeds picky where they germinate, they have a tough time getting started. Because the first year seedlings are small, they are easily killed during the first 6 or 8 weeks after germination. The second and third year seedlings can die from drought, drowning or inadequate light. For best growth, tamarack seedlings need abundant light and a constant but suitable water level.
Larch wood is tough and rot resistant, and the tree had a variety of historical uses. The root strings, tough and fibrous, were used by Indians to sew birch bark canoes. Hopefully, they figured out how to pull clean roots from under the ones in bogs. The name hackmatack comes from the Algonquain language for snowshoe wood. They also used the bark for medicine.
The colonists used larch for ship building. They harvested the roots that had grown at right angles to make ‘knees’ to join the ribs to the deck timbers. Today, the rather coarse-grained, hard, heavy and strong wood is used for planking, timbers, railroad ties, fence posts, telephone poles, shipbuilding and turpentine (from its European cousin).
Although not used much in landscaping because of its seasonal needle loss and forlorn winter appearance, UNH Extension Educator, Forest Resources, Jonathan Nute notes that in the Civil War era and earlier, “it was common to have one in a town cemetery to symbolize ‘death’ in the winter and ‘rebirth"’ in the spring.”
The European Larch (Larix deciduas) is used more in landscaping – it grows much larger than American larch, and tolerates warmer temperatures, so grows further south than native larch. On a spectacular fall drive in the high French Alps near Italy, we encountered a forest of huge pine trees that were a sickly yellow color. I thought they were all dying from air pollution. Due to French language limitations I was unable to find out what was wrong. Not until I became a Tree Steward years later, did I realize these were European larch trees showing their brilliant fall color before dropping the needles for the winter.
According to the national list maintained by American Forests, the largest larch tree in the nation is in Wells, Maine: 92 feet tall, a trunk circumference of 143 inches, and an average crown spread of 31 feet.
The NH Big Tree committee that maintains the official list of New Hampshire state and county champions is hopeful of finding champion trees in public places where others can admire them. So if you find a big larch tree anywhere, but especially one in a cemetery, that looks to be over 80 feet tall and a trunk a couple feet in diameter, contact Carolyn Page, NH Big Tree State Coordinator: carolyn_page@hotmail.com, 603-664-2934, so she can pass your information on to the appropriate county coordinator to arrange for volunteer Tree Stewards to take official measurements. To see the NH Big Tree list go to www.nhbigtrees.org, and look under tamarack to see the NH champions.
UNH Cooperative Extension and the NH Division of Forests and Lands sponsor the New Hampshire Big Tree program in cooperation with the National Register of Big Trees through American Forests.
by: Anne Krantz, NH Big Tree Committee
