Yellow-Cedar Tree Cookie
Yellow-Cedar Tree Cookie on Beacon Trail
Click on the image for a larger size photo.
The recent history of the yellow-cedar cookie on display in Lighthouse Park
In 2014 a 1.3 metre (52”) diameter 2-metre-long butt/stump of a yellow-cedar was reported on the beach east of the Dundarave Pier, West Vancouver. Three slices (cookies) were cut off it by the Parks Department, West Vancouver. Each slice was about 38 cm (15”) thick and weighed about 550 kg (1200 lb). It was proposed that one of the slices be used as a replacement for the Douglas-fir slice that was once displayed on the Beacon Lane Trail in Lighthouse Park. Two of our Directors, David Cook and Sally McDermott, took the lead for our Society on this exciting new project.
We contacted Dr. Lori Daniels (dendrochronologist, Faculty of Forestry, UBC) in the hope that her lab would do an analysis of the growth rings. In January 2019, she agreed to proceed with our request as there was a student (Spencer Bronson) available to do the study.
One of the slices, which had been sanded down by the District of West Vancouver Parks Carpenter (Earl Allen) to what we thought was a workable surface, was delivered to UBC Forest Sciences Centre by truck from the West Vancouver Works Yard and then off-loaded by forklift. Spencer was grateful that he had a flat, partly smoothed surface to work with. Nevertheless, he still had to spend hours sanding the specimen because yellow-cedar must be finely polished to see the very thin growth rings. The smoothed surface revealed very closely spaced and thin annual rings which were then scanned digitally. This was challenging because of the size of the sample.
It was hoped that the pattern of wide and narrow rings of the sample could be matched with known chronological patterns of other yellow-cedars from various areas along the coast of BC (and potentially Alaska) that were in the lab's archives. The overall pattern of the annual rings revealed that the tree had been highly influenced by weather patterns similar to trees in several BC coastal locations, suggesting close proximity to the ocean. This matching showed that the growth was most similar to that of trees on northeastern Vancouver Island. Also, some matches in growth were found when compared against trees on Haida Gwaii and, to a lesser extent, in Prince Rupert. It does not appear that the sample came from southeastern Alaska where much research on yellow-cedar growth has been conducted.
The ring dates ranged from 534 CE to 1982 CE, a period of 1448 years. The bark and an unknown number of annual rings had been eroded off during its time in the ocean. It could be a few years older.
The tree cookie was then returned to the West Vancouver Parks Department where it was stored until a suitable location in Lighthouse Park could be found. It was quickly agreed that a shelter should protect it, and funds were raised from the Lighthouse Park Preservation Society and the West Vancouver Foundation. A sturdy shelter was constructed by the Parks staff with a concrete base to hold the tree cookie. It is situated just east and below Beacon Lane Trail beside a picnic table. It was installed in December 2021. A celebration to 'introduce' it to the public was held on June 18, 2022. An interpretive sign was designed by Adrienne Nicholson with material provided by the Society and funded by the West Vancouver Foundation. The sign was put in place in July, 2022.
Click on the image for a larger size photo.
(Sally McDermott and Spencer Bronson wht the Yellow Cedar Round; photo credit: David Cook)
Further information about yellow-cedar:
What are the characteristics of yellow-cedar?
Also known as Alaska cypress or yellow cypress (Latin names are Chamaecyparisnootkatensis also known as Cupressisnootkatensis). “Yellow-cedar is the more used common name but Alaska cypress is more correct as it is not a cedar but a cypress and the scientific name, Cupressus nootkatensis, is preferred amongst taxonomists, based on molecular analysis.
Look for a tree trunk with silvery strips of bark. One of the most long-lived in our area, some living as long as 1600 years. Seed cones are spherical when green, about the size of a blueberry, opening to 4 to 6 scales when dry and brown. The scales sit on pegs like a conventional mushroom unlike a western redcedar whose scales are imbricated like shingles. Like the redcedar the butt is flared but not as deeply grooved. The bark is characteristically scaley. The inside of the bark smells like potato skins. The crushed leaves of yellow-cedar have an unpleasant, mildewy smell. Fresh cut yellow-cedar has a pungently pleasant smell. Some liken it to raw potatoes. Tiny scale-like leaves are arranged opposite each other in four, somewhat overlapping, rows. Like western redcedar, the neat rows of leaves along the stem look like a braid. Each leaf is sharply pointed at the tip, so if you stroke a branch away from you it will feel prickly, unlike a redcedar. The bark of young trees is smooth and reddish, but when the tree matures it becomes silvery gray to nearly white and may slough off in ribbon-like shreds. The bark is more brittle than western redcedar, which can be torn off in long strips. Yellow-cedar branches droop downwards while redcedar branches have an upward lift at the end of the branches forming a J-shape”(Old Growth Conservancy Society, n.d.). “The wood of yellow-cedar has natural extractives that make it decay-resistant and aromatic when cut. It is free from pitch and resin” (Forestry Innovation Investment, 2022).
Where does yellow-cedar grow on the North Shore?
Above 800 metres elevation.
What is a growth ring?
Each year of growth consists of two bands; a light band followed by a dark band. The growth rings of yellow-cedar are extremely thin and difficult to see. This is because the growing season above 800m in our local mountains or further north along the coast is short.
“The light band is the Spring Wood made of large cells which grew when the weather was wet. The dark band is the Summer Wood made of small cells formed when there was less rain. The two bands look different because the small cells of Summer absorb more light and therefore look darker.
[The] tree grows best during warm, wet weather. Each year [two] rings of wood are added to the sapwood in the trunk of a tree and to every branch; [one light band (the Spring Wood) and one dark band (the Summer Wood). In our area] when the weather gets cold in late Autumn and Winter, the tree stops growing. It begins to grow again the following Spring when the weather begins to get warm again.
Some tree rings are wide and some are narrow. Wide rings form during a year when the weather was very good for growth, such as warm and wet. Narrow rings form during drier years and cooler years”<span">(<span">Lamere, C, n.d.).
How do you tell the chronological age and provenance of our yellow-cedar?
“You’ll see rings of darker and lighter bands; 1 year of growth is composed of both a dark and light band” (Bowman, M., 2021). Since the darker bands are easier to distinguish, we counted the dark bands to estimate the age. Because the cookie slice was taken from close to the base of the tree, the actual age was more accurate. Imagine a tree’s growth rings are like a series of cones stacked on top of each other so that slices cut horizontally through the cone pile decrease the number of cones (years) as you slice higher and higher through the pile of cones. The chronological years can be determined by comparing the ring pattern with other yellow-cedar samples with known dates. From such matches, we know this tree lived until around 1982 CE. The bark and an unknown number of annual rings had been eroded off during its time in the ocean, so it could be even older. However, if the end of its life is estimated to be 1982 CE then its age is about 1448 years.
And its provenance? Matching growth ring patterns with samples in the UBC reference collection of yellow-cedars with known locations showed a similarity to the growth ring patterns of trees on the north eastern coast of Vancouver Island. Also, some matches in growth patterns were found when compared against trees on Haida Gwaii and, to a lesser extent, in Prince Rupert.
Can the rings tell you anything about past climates?
“The rings can also tell you about the environmental conditions for a particular year. Thinner rings represent colder or dryer years, and thicker rings represent better growing conditions” (Bowman, M., 2021).
What are the uses of yellow-cedar?
“Yellow-cedar has exceptional longevity and is very durable. It is an excellent choice for shingles, posts, poles, marine pilings, small boat hulls, oars and paddles, water and chemical tanks, exterior doors and window boxes. Structural grades are commonly used for exterior applications such as bridges, decking and stairs and for landscaping. It is sometimes used in specialty construction projects such as temples and shrines.
Yellow-cedar is well suited for flooring and bridge decking because of its strength, hardness and wearing properties. It resists corrosion and the elements so it is ideal for industrial uses like flumes, chemical containers, horse stables, floors or outdoor seating in sports facilities. It is used extensively for boat building, sauna manufacturing, fine cabinetry and interior and exterior millwork.
Indigenous peoples use almost every part of a yellow-cedar tree. Roots are dried and braided to make hats and baskets. Withes are strong, lightweight and naturally grow in long strands, so they are suitable for ropes and lashing. Bark is dyed and processed into thread for mats, clothing, blankets and hats. Bark is also used for ropes, baskets and fishing nets. Inner bark is soft, so it has been used for baby diapers, bedding, sanitary napkins and towels and clothing. Dried bark is an excellent tinder for matches and torches. Cedar wood is used for totem poles, masks and longhouses, as well as canoes, paddles, hooks, spears and fishing floats. Fish are preserved in cedar smokehouses or dried on cedar racks. Yellow-cedar is also used by Indigenous people to make bentwood boxes to store food or other goods. The boxes are made from a single cedar plank which is steamed until pliable and then bent. The two sides are pegged together. The boxes are decorated with paint or carvings” (Forestry Innovation Investment, 2022).
References
· Lamere, C, (n.d.). How old is that tree? Retrieved July 29, 2022 from https://www.grandpacliff.com/Trees/TreeAge.htm
· Old Growth Conservancy Society. (n.d.). Identification characteristics of trees in OGC and adjacent areas. Retrieved July 30, 2022, from https://ogcs.ca/wp-content/uploads/OGC-Tree-Identification.docx
· Forestry Innovation Investment. (2022, March 16). About Yellow Cedar - tree identification, properties & uses - softwood species: Naturally:wood. naturally. Retrieved July 29, 2022, from https://www.naturallywood.com/species/yellow-cedar/
· Bowman, M. (2021, May 24). 4 Ways to Determine the Age of a Tree. wikiHow. https://www.wikihow.com/Determine-the-Age-of-a-Tree
· Dendrochronology. (n.d.). [Illustration]. Archaeological Dating. https://www.crowcanyon.org/education/learn-about-archaeology/archaeological-dating/
Additional Suggested Reading
· Harris, A.S. (1990): Chamaecyparisnootkatensis. Pp. 97-102 in R.M. Burns and B.H. Honkala (technical coordinators) Silvics of North America, Vol. 1. Agri. Handbook 654, USDA For. Serv., Washington, D.C. https://www.fs.usda.gov/treesearch/pubs/1547
· Pojar, J. & MacKinnon, A. (1994): Plants of Coastal British Columbia including Washington, Oregon & Alaska. B.C. Forest Service, Research Programme. LONE Pine Publishing.
· Ministry of Forests. (2021, November 8). Alaska yellow cedar - Province of British Columbia. Government of British Columbia. https://www2.gov.bc.ca/gov/content/industry/forestry/managing-our-forest-resources/silviculture/tree-species-selection/tree-species-compendium-index/alaska-yellow-cedar
· Wikipedia contributors. (2022, July 26). Callitropsisnootkatensis. Wikipedia. https://en.wikipedia.org/wiki/Callitropsis_nootkatensis