Trees of Life

Western Redcedar

In the Pacific Northwest, the Western Redcedar (Thuja plicata) is often called the "tree of life." In fact, the use of it's wood and bark it's one of the defining features that represents the northwest coast indigenous cultures. Its wood is infamously rot-resistant, and since it's also easy to split it's an ideal resource, particularly in such a wet climate. Redcedar's slow decay time also makes it a very important tree ecologically, as logs persist in the understory of old growth forests (some species, including Western Hemlock, germinate almost exclusively on these "nurse logs") and in streams. Large wood is an important feature of streams because 1) the persistent wood releases nutrients into the stream slowly over time (attracting macroinvertebrates, which are then fed on by juvenile salmonids), 2) it creates a physical impediment to fast water flow, resulting in pools that spawning salmon use to rest in during their arduous journey upstream, and 3) it provides cover for juvenile salmonids as they rear in the stream.

Western Redcedar is a prevalent tree in low to medium elevations, and its cultural uses included, but are not limited to, the following:

• The wood was used to make canoes, house planks, totems, and mortuary poles.
  
• Wood was also used for such tools as arrow shafts, spear shafts, barbecue sticks, fish spreaders, bowls, dip net hooks, cradles, and coffins.
• The wood makes an excellent fuel, particularly for drying fish.
• It was said to possess healing and spiritual powers.
• Bark was used for making blankets, clothing, and baskets.

American Chestnut

If Western Redcedar was the tree of life on the Pacific Northwest coast, then the American Chestnut (Castanea dentata) was at one time the tree of life in the eastern deciduous forests. It was a dominant tree throughout most of its range, which spanned from Maine nearly to the Gulf coast, broadly following the arc of the Appalachians. It was ecologically important because it reliably produced crops of chestnuts every year. Since its functional extinction, oak species have primarily filled its niche, but oaks produce large crops of acorns some years, and small to no crops in other years. This puts stress on the myriad of species that depend on this food source, and results in wildly fluctuating populations between years. Commercially, chestnut lumber was valued for furniture, musical instruments, interiors, caskets, and fences. In addition to possessing quality wood, the chestnut's growth habit tended toward a tall, straight trunk making it extremely attractive for logging.

In the early 1900's tragedy struck as the Chestnut blight (a fungus of presumabely Asian origin) decimated the species. It is functionally extinct, though you may still find specimens in the wild. The blight does not destroy the roots, and so the tree will still send up sprouts which can reach "moderate" heights (the tallest I've seen was approximately 7-8 ft. tall) before they succumb to the blight. These sprouts rarely survive long enough to produce flowers and fruits. There is some work being done to hybridize American Chestnuts with foreign species to produce a blight-resistant tree, but as far as I know success is limited and these trees are primarily used as ornamentals.

I can't remember if I read this somewhere, or saw it on a documentary, but there was an elderly man recounting the beauty of flowering chestnuts in the spring. He lamented their loss, both in an ecological sense and a personal sense, since he can never again behold that spectacle. He then went on to say that it was unfortunate how younger generations never got to witness the American Chestnut as a dominant component of eastern forests. Having never seen them, they aren't even aware of what they missed out on. He implied with deep sadness in this statement that extinctions really only hit home for the generations that witnessed them. For the majority of people, this is probably true. For some reason though, I've developed an odd emotional attachment to the American Chestnut. I get legitimately upset when I see chestnut sprouts, because I know that they'll never survive and yet they're right in front of me! It's incredibly frustrating to me, despite the fact that I've never seen a mature chestnut. I have the feeling that I'm looking at a ghost, and in some ways I am. This was a site of a mighty chestnut, and now all that remains is this spectral sprout, unnoticed by most humans as just part of the understory, and by the species that used to depend on it as just another plant that doesn't provide a source of fruit. Of course with functional extinction there's always the hope that hybridization will be successful and chestnuts can once again thrive despite the blight. But how likely is it that the tree will make an ecological comeback? There's really no way of knowing, but one thing is for certain: even if a resistant chestnut is successfully bred or engineered, it will be generations before the world sees eastern forests with an ecologically dominant chestnut.

References:

Pojar, J. and MacKinnon, A. 2004. Plants of the Pacific Northwest Coast. B.C. Ministry of Forests and Lone Pine Publishing, Vancouver, B.C.

Petrides, G. A. and Wehr, J. 1998. Peterson Field Guide to Eastern Trees. Houghton Mifflin, New York, NY.