Culturally modified tree

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A culturally modified tree in Gifford Pinchot National Forest, Washington, USA

Culturally modified tree (aka CMT) is a term which describes the modification of a tree by indigenous people as part of their tradition. Their meaning for the indigenous cultures is relatively well known, but only from the beginning of the 1980s scientists have recognized that they are also important sources for the history of certain regions. They are even called CMT archives. Although a wide range of results has been produced, and progress has been made as far as methodology is concerned, the CMTs are still rather unknown to the public.

In British Columbia one of the most commonly modified trees, particularly on the coast, is the Western Red Cedar. Of these, many involve the removal of the inner and outer bark, for use in basketry and other needs.

Many old trees wearing blue belts with the words "culturally modified tree" in Stanley Park/Vancouver have attracted considerable interest - and questions.[1]


Although limiting CMTs to indigenous people is not coercive, the term is used this way in western Canada and the United States. In northern Scandinavia and Southeast Australia it is used for the same phenomenon in view of the Sami people and Indigenous Australians, respectively. There are also research projects occupied with Basque herders who left thousands of trees in the western USA between 1860 and 1930.

The modifications can be arboglyphs or arbographs, that is carvings or paintings, but these are relatively rare. Much more often are trees of usage left by canoe makers, or when people were in need of fibres for making clothes, hats or blankets.

Protection, registration and analysis of CMT-Archives[edit]

In British Columbia, Canada, these trees are protected by complex laws. Trees dating before 1846 and registered as CMTs are not allowed to be logged. The first lawsuit concerning CMTs was against a Canadian who had logged CMTs over 300 years old.[2] No license was given between 1996 and 2006, but in that year it was allowed once again - against the resistance of the Haida on Haida Gwaii. Even if loggers accept the restrictions and spare a CMT, these trees are endangered because they lose their "neighbours" and with them the protection against heavy storms. Consequently, Hupacasath First Nation on the western shore of Vancouver Island claim a protective zone around the trees of at least 20 to 30 metres.[3]

The trees are registered, classified and, if possible, dated; the trees are identified and correlated with certain activities or rituals of the First Nations. There are numerous prescriptions for how to register and accumulate the findings. Sophisticated forms were developed to facilitate both the process and the analysis.

The reasons for this elaborate process are on the one hand the meaning for rituals and cultures of the First Nations living in Temperate rain forests. These peoples are very interested in the protection of their archives that consist of old and sometimes extremely high trees that reach nearly 100 m.

On the other hand, the trees are a source of utmost importance for the history of the First Nations (and not only for them), a history that is heavily dependent on oral traditions and archeological findings for the pre-contact phase.

This causes many problems for historians, ethnohistorians, anthropologists. The logging industry, first of all, requires clear guidelines concerning which trees they can log. Clearcuts have reduced the old forests to a minimum in most regions and thus destroyed the archives. Many people do not recognize the significance of CMTs and often do not even see the trees. Finding these artefacts is also a problem in areas far away from any infrastructure, so scientists must rely on local knowledge.

Another problem is that knowledge of these places is not necessarily public. That is the case with many Nuu-chah-nulth on Vancouver Island. Only that group knows the corresponding rituals, devices, stories and dances, so their consent is needed.

The tiny Island of Flores is home to 71 registered culturally modified trees which are protected like archives, libraries, historic sites or memorials.

Beginnings of examination[edit]

Before the 1980s scientists did not recognized the potential of the CMT archives. Hebda and Mathewes pointed out that they could deliver traces up to 5000 years old. After historians and the courts had recognized that the trees of Meares Island are crucial for culture and history of the Indian Nation living there, other indigenous groups started to register CMTs in their own reserves and in their traditional territories to get the same protection for them. Historians and Indians worked closely together.

Frequent species and their ways of usage[edit]

Gottesfeld could detect 21 species, which played a certain role as CMTs. Of utmost importance is the Western red cedar (Thuja plicata), but the yellow cedar (Chamaecyparis nootkatensis), spruces (Picea glauca u.a.), hemlock (Tsuga heterophylla), pines (Pinus contorta, Pinus ponderosa), in addition Populus tremuloides, Populus trichocarpa and Alnus rubra are also quite frequent. The bark of hemlock and certain spruces was important for nourishment and medicine. The resin of spruces was used as a kind of glue.

But the most often traces are peeled trees - besides traces of planks, canoes, totem poles and house posts. In addition you often find test holes, because, before starting their work, the people wanted to know if the bark or the wood were all right. Sometimes they only needed dry bark or tinder to make fire.

Development and results of some research projects[edit]

In 2001 Prince examined British Columbian lodgepole pines (Pinus contorta). Their bark is quite nutritious, if adequately prepared. Prince found two areas, in which the main nutrient was salmon, but in one area it was abundant all year through, in the other there occurred heavy lacks of salmon irregularly (White Eye Lake). He found out that in the less reliable area there were years of heavy concentration of peelings, especially in the years 1810, 1880, 1910, and 1925. None of these areas was "harvested" twice. The bark was obviously a kind of emergency reserve, as a surrogate for the salmon. In the more reliable area he could not find any concentration of this kind. In addition, this tribe needed a much smaller territory than the one with the "times of hunger".

CMTs have become important for the history of Scandinavia, too. The Sami people, who also ate certain kinds of bark, were displaced northwards in the 19th century by the Swedish population, who did not eat bark. Consequently, the traces of bark peelers are interrupted from one year to the next, so that historians can exactly tell when the last Sami left the region under examination. The oldest finding ever registered is 2800 years old. Meanwhile, the methods are so much refined that even fossile trees have become an important source for human history. The oldest living CMT was found in British Columbia. It dates back to the 12th century.[4]).

The role of cedars, spruces etc. are taken over by much different species in Australia. Here the red (river) gum (Eucalyptus camaldulensis) and the grey box (Eucalyptus moluccana) are of most importance. There are certain similarities as far as the usage is concerned. Rhoads published in 1992 that within the territory of Southwest Victoria (about 10,000 km²) 228 CMTs were found. In most cases they were found in the vicinity of ancient camps. The other way round: Search is much more promising around these trees, if you are looking for ancient camps.

The most surprising fact was a consequence of research within the Bob Marshall Wilderness in northwestern Montana. This is a wilderness of about 3,000 km² (in addition another 3000 of neighbouring wildernesses) that was never used by non-aboriginal people. There are no houses, streets, fields or pastures. Nevertheless, the CMTs showed that between at least 1665 and 1938 indigenous people peeled the bark and conducted other uses.


No historical source - leave alone the cultural meaning - is so heavily endangered, and on the other hand as precise, as the CMT archives. They open new research fields, but need very exact methodology. A crucial precondition for research is the preservation of old growth forests. So in addition to ecological, cultural and other scientific reasons to keep them alive, they are historic sites of highest rank.

Countries whose forests are at least partially untouched, have in most cases not yet realized what they have in front of their doors. For example, for the history of northern Asia, they can frequently be the only witnesses of the past. Once destroyed, the history is forgotten forever.

In Canada, where research was for obvious reasons concentrated in the western provinces with its old forests, Ontario has documented CMTs in 2001. In Nagagamisis Provincial Park most trees found were between 80 and 110 years old, some probably more than 400.

On Hanson Island alone, David Garrick documented 1800 CMTs. The Kwakwaka'wakw of the region could stop the destruction of their archive. Garrick also found trees in the Great Bear Rainforest on the territory of the Gitga'at First Nation. They are supposed to be logged for a street in the area of Langford. In February 2008 the Times Colonist reported of protesters being removed.[5]

In 1985 a protection program was started in Washington's Gifford Pinchot National Forest. At 338 spots more than 6000 CMTs were identified, of which 3000 are protected now.

17 CMTs were found in the Blue Mountain area within Pike National Forest, at least 26 in Florissant Fossil Beds National Monument. Trees more than 200 years old were registered in Manitou Experimental Forest north of Woodland Park. Most of these trees within the territory of the Ute are ponderosa pines. Researchers know that they haven't got that much time. The trees have a life-expectancy of 300 to 600 years. Many could be dated, being peeled between 1816 and 1848. In February 2008 the Colorado Historical Society decided to invest a part of its 7 million dollar budget into a CMT project in Mesa Verde National Park.[6]


  1. ^ E. g. a picture from Flick'r: Culturally Modified Tree
  2. ^ CBC News v. 17 November 2000: Culturally modified tree-cutting trial resumes
  3. ^ Hupacasath land use plan, phase 2, prepared by Tom Whitfield for Hupacasath Band, o. O., o. J. (probably 2005), 44 pp., p. 14.
  4. ^ Zackrisson et al. 2000
  5. ^ Bill Cleverley, RCMP move in on anti-highway protest site, in: Times Colonist, 13 February 2008.
  6. ^ Nach [State Historical Fund awards more than $7M in grants, in: Denver Business Journal, 14. February 2008].


  • R. Andersson, Historical Land-Use Information from Culturally Modified Trees, Diss. Swedish University of Agricultural Sciences, Umea 2005
  • M. Antrop, Why landscapes of the past are important for the future. Landscape and urban planning 70 (2005) 21-34
  • Arcas Associates, Native Tree Use on Meares Island, B.C., 4 volumes, Victoria 1986
  • I. Bergman/L. Östlund/O. Zackrisson, The use of plants as regular food in ancient subarctic economies. A case study based on Sami use of Scots pine innerbark. Arctic anthropology 41 (2004) 1-13
  • M. D. Blackstock, Faces in the forest: First Nations art created on living trees. Montreal/Kingston: McGill-Queen's University Press 2001, 224 pp.
  • G. Carver, An Examination of Indigenous Australian Culturally Modified Trees in South Australia. Doctoral thesis. Department of Archaeology, Flinders University, Australia 2001
  • Juliet Craig: "Nature was the provider". Traditional ecological knowledge and inventory of culturally significant plants and habitats in the Atleo River Watershed, Ahousaht Territory, Clayoquot Sound, PHD. Victoria 1998
  • V. V. Eetvelde//M. Antrop, Analyzing structural and functional changes of traditional landscapes: two examples from Southern France. Landscape and urban planning 67 (2004) 79-95
  • T. S. Ericsson, Culture within nature: Key areas for interpreting forest history in boreal Sweden (Acta Universitatis Agriculturae Sueciae), 2001
  • David Garrick, Shaped Cedars and Cedar Shaping: A Guidebook to Identifying, Documenting, Appreciating and Learning from Culturally Modified Trees. Special Limited Edition, Western Canada Wilderness Committee, 1998.
  • L. M. J. Gottesfeld, The importance of bark products in the aboriginal economies of northwestern British Columbia, Canada. Economic botany 46 (1992) 148-157
  • R. J. Hebda/R. W. Mathewes, Holocene history of Cedar and Native Indian cultures of the North American Pacific coast. Science 225 (1984) 711-713
  • L. M. Johnson, "A place that’s good". Gitksan landscape perception and ethnoecology. Human ecology 28 (2000) 301-325
  • J. Mallea-Olaetxe, Speaking through the aspens: Basque tree carvings in California and Nevada. University of Nevada Press, Reno / Las Vegas 2000, 237 pp.
  • Amanda L. Marshall, Culturally modified trees of the Nechako plateau: cambium utilization amongst traditional carrier (Dahkel) peoples. Master's thesis. Department of Archaeology, Simon Fraser University 2002
  • C. Mobley, The Ship Island site: Tree-ring dating the last battle between the Stikine Tlingit and the Tsimshian. A report to the Alaska Humanities Forum, Grant 1999, 36-96
  • C.M. Mobley and M. Eldridge, Culturally Modified Trees in the Pacific Northwest. Arctic Anthropology. 29 (1992) 91-110.
  • J. Oliver, Beyond the Water's Edge: Towards a Social Archaeology of Landscape on the Northwest Coast. Canadian Journal of Archaeology 31 (2007) 1-27.
  • B. Pegg, Dendrochronology, CMTs, and Nuu-chah-nulth History on the West Coast of Vancouver Island. Canadian Journal of Archaeology 24 (2000) 77–88.
  • P. Prince, Dating and Interpreting Pine Cambium collection Scars from Two Parts of the Nechako River Drainage, British Columbia. Journal of Archaeological Science 28 (2001) 253–263.
  • Sheila D. Ready, Peeled Trees on the Payette National Forest, Inner Bark Utilization as a Food Resource by Native Americans, USDA Payette National Forest, Supervisor's Office, McCall, Idaho 1993
  • J. W. Rhoads, Significant sites and non-site archaeology: a case-study from south- east Australia. World archaeology 24 (1992) 199-217
  • Arnoud H. Stryd/Vicki Feddema, Sacred Cedar. The Cultural and Archaeological Significance of Culturally Modified Trees, digital (PDF, 1,3 MB): Stryd/Feddema
  • A.H. Stryd and M. Eldridge, CMT Archaeology in British Columbia: The Mears Island Studies. BC Studies 99 (1993) 184–234.
  • T. W. Swetnam, Peeled ponderosa pine trees: A record of inner bark utilization by Native Americans. Journal of ethnobiology 4 (1984) 177-190

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