On Cranberries

Lowbush cranberry or lingonberry, Vaccinium vitis-idaea growing in moss under pine. Southern Yukon 2004.
A year ago I wrote more generally on the ethnobiology of Thanksgiving. Today I want to write about cranberries. Botanists have been somewhat indecisive about whether cranberries are, as it were, a red wetland-dwelling blueberry with a very tart flavour, or whether they should be segregated in a genus of their own, Oxycoccus (‘sour ball’) because of their trailing stems and vine life form, and their azalea like pink flowers which differ from the little heather urn-shaped flowers of blueberries, blaeberries, huckleberries, whortleberries, bilberries and their ilk. And of course their eponymous sour fruits, while blueberries are generally sweet when ripe. The cranberry of commerce is the large New England species designated Vaccinium macrocarpon if we take the position that “true” cranberries belong in the genus Vaccinium. This is the large tart berry associated with Thanksgiving sauces and jellies, and now ubiquitous in the form of jugs of sweetened cranberry juice and also common as dried sweetened cranberries. These cranberries find their native habitat in acidic wetlands, that is, in peat bogs. In the course of researching this blog I have learned that, although natural wetlands were formerly the sites of cranberry cultivation, now industrial cultivation involves stripping the fertile soil and leveling the future cranberry field, and surrounding it with dikes made of the topsoil, while placing acidic sand on the carefully leveled field. These diked fields are then managed in a manner reminiscent of rice paddies, being carefully flooded at specific times in the growth and harvest cycle of the fruit. I read that industrially produced cranberries are harvested by flooding the fields and sucking up the floating berries with huge mechanical harvesters. These fruits, often bruised, then are immediately processed into canned cranberry jelly or sauce or perhaps for juice. Apparently to get a quality that can be sold as unfrozen berries, you have to harvest the fruit dry, and humans run the machines that pick these higher quality berries, a mere 2 or 3% of the cranberry harvest. At some point in the past, there was a scare about pesticide contamination, so industrial growers are now very careful with the chemicals they apply.
Although a lot of commercial cranberries are no longer cultivated in wetlands, cultivation on the periphery of wetlands in soils naturally moist and acidic still occurs. This cultivation has the predictable effect of altering the hydrology of wetland areas, and can introduce chemical contamination from agricultural chemicals (e.g. nitrogen or pesticides) applied to the crop. As bogs are naturally highly oligotrophic (low in nutrients) this can cause decline in native bog species on the periphery of the cultivated area and invasion of weedy species, threatening unique bog ecosystems. Not to mention the decline of biodiversity in the cultivated plots themselves. Cranberry cultivation has been one of the threats to Burns Bog, a large peatland wetland area on the Fraser River Delta in British Columbia which exists in the midst of extensive urban and cultivated agricultural landscapes. This site is highly revered for its wildland bog habitat and recreation potential within the Lower Mainland, but has also been threatened with a number of schemes for its transformation or elimination, from housing developments to landfills, and its sensitive hydrology is threatened by various proposed dikes and drainage ditches. I recall learning about the environmental risks of the commercial cultivation when I still lived in BC, and there was concern about contamination with agricultural chemicals. This led me to try to buy organic cranberry products whenever possible.
What makes a cranberry? The classic cranberries of bogs (Vaccinium macrocarpon, V. palustris, V. oxycoccus) are viney evergreen members of the heath family living in peatlands, and which have persistent tart red fruits that develop from lovely spreading pink flowers. In northwestern North America we would call these “bog cranberries” and our local species has much smaller leaves and fruits than the classic cranberry of commerce, and is much lower in productivity. The taste is the same. And we also have what we would call “low bush cranberry”, which I have also seen rendered as “mountain cranberry”. This is Vaccinium vitis-idaea, the “blueberry” ‘grapevine of Mt. Ida’, also a low growing, but not viney, member of the genus Vaccinium with glossy evergreen leaves, usually growing in moss…but here the feather moss of spruce or pine stands, not usually of sphagnum bogs….which has small tart red fruits that taste like cranberries. These develop from classic heather family urn shaped flowers of white or very pale pink. In Scandinavia, where they are revered, they are lingonberries, and a national food of Sweden. When I have the opportunity, these are what I pick during late summer fieldwork to freeze for my Thanksgiving cranberry sauce. Alas, not only was it a poor berry year this past summer, I left the Yukon too early, before the cranberries were even minimally ripe. So it will be purchased V. macrocarpon for me this year.
Cranberries (aka lingonberries) are one of the most important fruits for northern Athapaskans. For Gwich’in in the Mackenzie Delta region of the Northwest Territories there are “yellowberries” nakal (Rubus chamaemorus, the cloudberry) a golden bog dwelling raspberry, blueberries (Vaccinium uliginosum, the bog blueberry) and cranberries. Cranberries last the longest, keep the best, and can be harvested in larger amounts. In the boreal forests of the southern Yukon, Kaska love cranberries too. They are called itl’et in Kaska, and people pick and freeze relatively large amounts. Cranberries can be eaten in the spring after they thaw. Anore Jones quotes a poignant tale of death and survival of a Yupiq woman in her “Plants that we eat” (1986 Maniilaq Association). A woman who was widowed and travelling alone with two small children managed to survive on sparse spring cranberries. One of her two children also made it. This was the grandmother of one of the elders Jones worked with in the 1980’s.
Cranberries are good for more than survival. A Kaska elder friend said she treated her husband’s urinary tract infection by feeding him cranberries. Contemporary herbal medicine also suggests cranberry juice, or cranberry capsules, for prevention of urinary tract infections or chronic cystitis. Cranberries, along with blueberries, apparently contain lots of anti-oxidants, considered to be cancer preventative through combination with free radicals. I buy cranberry capsules at my local organic food store which I take faithfully to prevent cystitis.
The Wikipedia article on “cranberry” mentions that some species of Viburnum are also called “cranberry”, which they consider erroneous. No, merely ethnobotanical…fruits of various species of Viburnum, locally V. edule and V. trilobata have red fruit that ripens in the fall and it is the gustatory quality of astringence, sour and a bit bitter, which makes them “cranberry”, not their botanical affiliation (they are in the Caprifoliaceae or honeysuckle family, and grow on tall woody bushes). Though they have large flat white seeds which make the fruit dissimilar to “real” cranberries to eat, they make a fine sauce or jelly. They lack the large amount of pectin of true cranberries, so the sauce is runny…but delicious. I wrote last fall on highbush cranberries (aka the Viburnums). I’ve been snacking on them as I walk in the ravine by my house. I’ll close now and wish everyone a happy Thanksgiving, and hope they are enjoying cranberries in one way or another to mark the holiday.

Sources:
http://en.wikipedia.org/wiki/Cranberry
http://peterwood.ca/res/research/burnsbog/Burns%20Bog%20Protection%20Values%20and%20Management%20Options.htm
Jones, Anore. 1983. Nauriat Nigiñaqtuat, Plants That We Eat. Kotzebue, Alaska: Maniilaq Association.

other sources which discuss cranberries:
Parlee, Brenda, Fikret Berkes and Teet'it Gwich'in Renewable Resource Council. 2006. Indigenous Knowledge of Ecological Variability and Commons Management: A Case Study on Berry Harvesting from Northern Canada. Human Ecology 34(4):515-528.
Andre, Alestine and Alan Fehr. 2001. Gwich’in Ethnobotany, Plants used by the Gwich’in for Food, Medicine, Shelter and Tools. Inuvik: Gwich’in Social and Cultural Institute and Aurora Research Institute