Eastern Hemlocks

Eastern Hemlocks -- © Dave Spier

Of all the trees in New York, the Eastern or Canadian Hemlock (Tsuga canadensis) is probably my favorite. In old growth forests it is capable of living more than half a millennium. It’s a chief component of the climax forests found in the Adirondacks (generally at lower elevations below 2500'), the Catskills, the Lake Ontario shoreline, bog edges, the glens of the Finger Lakes Region and down across the Allegheny Plateau and Appalachian Mountains. In Pennsylvania, it is the state tree.

Eastern Hemlocks occur naturally from Wisconsin and Michigan eastward to the Canadian Maritimes and south through New England and the Mid-Atlantic states to the Appalachians of Tennessee and North Carolina where it is under attack by the wooly adelgid bug. When we re-visited Shenandoah National Park, it was sad to see the mighty groves of old-growth hemlocks reduced to skeletons and dead logs.

Laricobius nigrinus beetles, which are native to the Pacific Northwest, prey on the hemlock wooly adelgid, but I have not kept up on efforts to use them in the fight against the infestation. Cornell was involved with a test in the Finger Lakes region, where the problem is still minor. Cold winters work against the adelgid, but global warming could change that.

At their northern limit, hemlocks can grow at sea level, but the farther south one travels, the higher its preferred elevation. It is essentially a cool-climate evergreen that does better in areas with extra moisture or humidity. Annual precipitation ranges from 30 inches in the north to 60 inches in the south.

Like the Sugar Maple and American Beech, the hemlock grows well in the shade of other trees and, like its associates, it can reach heights of 100 feet. Under the right conditions, it has reached a record height of 173 feet in the South. The trunk of old trees can reach a diameter of five feet at chest height, and the record is six feet. The bark is dark brown and rough, often fissured with age, and was once a source of tannin used in tanning leather. The lumber was used for railroad ties.

For a tree that can grow to such large size, its cones are remarkably tiny and may barely reach an inch in length. Its needles also are small. Unlike pines and spruces, hemlock "needles" are flat, rounded at the tips and they line both sides of the flexible twigs. This is an advantage in shedding snow before the twigs and branchlets break. The undersides of the needles are whitened with two stomatal bands that allow the exchange of gases with the air. The half-inch long needles are attached to twigs by slender stalks, unlike Balsam Fir needles which are flat but attach directly with circular bases. The needles of all conifers can be used to make a tea rich in vitamin C.

The undersides of hemlock needles -- © Dave Spier

Incidentally, hemlocks make poor Christmas trees because the needles fall as soon as they dry. It’s best to leave them growing because the seeds and needles provide food for Ruffed Grouse and twigs are eaten by deer, Red Squirrels and even cottontail rabbits.

In early spring, before the deciduous trees leaf out, the hemlocks add a welcome touch of green along with mosses, a few evergreen ferns and Skunk-cabbage leaves. On a clear morning, enjoy the sunlight streaming through the evergreens.

Questions, additions and corrections may be sent to The Northeast Naturalist.  There is a discussion of hemlocks in Michael Kudish's book, Adirondack Upland Flora.

Tree of Peace

Bundles of Eastern White Pine needles surround next-spring's bud at the tip of a twig. 
© Dave Spier  [1-5X macro lens at 2X on full-frame sensor + twin macro flash]

Tree of Peace

© Dave Spier

To the Iroquois, the Eastern White Pine (Pinus strobus) was known as the "Tree of Peace" and it symbolized the Great Law of Peace that united five tribes into one confederacy or league, thus ending decades, and probably centuries, of conflict between these groups.  The date is unknown, but precedes white settlement of Upstate New York.  Estimates range from 1100 A.D. to somewhere in the 1500's. 

The Iroquois called themselves Haudenosaunee, or People of the Longhouse.  The name "Iroquois" is a French transliteration from derogatory terms used by the Hurons (in Canada) and Algonquins (from New England to the mid-Atlantic), both enemies of the Haudenosaunee.

All pines have leaves that grow in bundles of two, three or five needles bound together by a sheath where they emerge from the twig.  White pines have clumps of five needles, and to the Iroquois Confederacy, these symbolized the original Five Nations: Seneca, Cayuga, Onondaga, Oneida and Mohawk.  What is now the Adirondacks was divided by the Oneidas to the west and the Mohawks to the east.  The Tuscaroras, after being displaced from North Carolina, were eventually admitted to the Confederacy and merged with the Onondagas and Oneidas in central New York.

White pine needles, generally three inches long, are thin, soft and flexible.  It's easy to "shake hands" with a white pine (whereas many other pines have stiff, prickly needles).  The name of this species comes from fine, whitish stripes along the length of the green needles, but you'll probably need a magnifying glass to see them clearly.  During their second year of growth, the needles turn yellow and fall.

Cones are generally six inches long and easy to handle.  Many pines have shorter, compact cones with prickles at the tips of their scales.

White pines can reach great age and size.  Many old pines that survived logging in the Adirondacks are over 300 years old.  One near Syracuse was dated at 458 years.  Mature trees easily tower over their deciduous compatriots.  In pre-colonial America, specimens were reported at 230 feet high and these were later reserved by the king to become ship masts in the British Royal Navy.  The current Eastern White Pine record holder in the Great Smokies reaches 188 feet.  (It was 207 feet high before a hurricane took off the top.)

Corrections and questions may be sent to northeastnaturalist@yahoo.com

Autumn Gold -- © Dave Spier

Mention the word "conifer" and it's likely the concept of "evergreen" comes to mind. Most groups of conifers keep their needles through the winter. One big exception is the larch, or tamarack, the only common deciduous conifer. It turns gold in the fall (roughly the third week of October) and then drops its needles. During the winter, when the twigs are bare, take a closer look at the knobby texture of the year-old twigs.

Larch needles grow in dense, radial clusters supported by short, woody knobs on the sides of last year's twigs. One cluster can have 30 needles growing in a circular whorl. On this year's twigs, the soft needles grow singly.

Larches begin flowering at 15 years of age. The male flowers are tight clusters of stamens, while the female flowers are larger, scaly rosettes. Like other members of the Pine family (Pinaceae), they are wind pollinated. The female "larch roses" develop into barrel-shaped cones with overlapping scales and hollow tips. Immature seed cones are bright red. They grow upright on the ridged twigs, reach a length of a half inch or slightly more, then turn brown as they mature and may persist for several years. Inside the cone scales are brown seeds with firmly-attached, membranous (papery) wings affixed at one end.

October snow on larch (tamarack) branches before the needles fall - note all the cones. Natural Bridge, NY - © Dave Spier

Larches are related directly to pines and less directly to spruce, hemlock and Balsam Fir. All of these conifers produce so-called naked seeds. The Greek word for naked is gymnos, and yes, it's the original root of the word gymnasium. Combine this with sperma, the Greek word for seed or germ, and you get the botanical classification gymnosperm. (Other members of this group include yews, redwoods, cycads, cedars, cypress and the Ginkgo.) By contrast, angiosperms, or flowering plants, are evolutionarily more modern. Their seeds are enclosed by the ovary.

The native Eastern [American] Larch (Larix laricina) grows in bogs and boreal (northern coniferous) forests wherever it can get enough sunlight. It is one of the pioneer tree species but cannot grow in the shade of other trees. Overall, larch is now more abundant than it was before the logging of the late 1800's and early 1900's opened the forest canopy and allowed more light to reach the ground. (The Boreal Life Trail at Paul Smiths is a good place to see larches in their natural habitat.) Altitude is little hindrance to larches; they grow at 4620' on Haystack. At lower elevations, larches can reach heights of 60 to 80 feet, but still die out as mature forests reclaim the land and close the canopy, thereby preventing rejuvenation from seedlings.

European Larch (Larix decidua) is widely planted as an ornamental and for timber harvesting. Pure stands of tall larches are very likely this species.

Fortunately, larches are still commonly called Tamaracks (Algonquian). "Larch Lodge" just doesn't have the ring of "Tamarack Lodge."

Okay, I'm late getting around to this post, but other comments and corrections may be sent to northeastnaturalist@yahoo.com