Flour from forests
Bread and flour are staple foods for many cultures around the world. It is possible to produce flour from cereals such as maize and wheat, or from fruits such as chestnuts or acorns, but few people know that some North European and North American peoples used to make flour from tree bark. In periods of exceptional frost or during famine and wars, the Nordic peoples could count on an abundant and hard-to-deplete food resource: ground bark. Archaeological sources have shown that this food was already in use among the Norse (people living in northern Europe) during the 9th century, although it probably originated from much earlier times. A more recent use of ground bark dates back to the 18th century, during what was called the ‘Little Ice Age’, a period between the 14th and 19th centuries when there was a drop in the earth’s average temperature. Cereal harvests were severely impacted by falling temperatures, forcing the Nordic peoples to devise ways of making the scarce reserves of traditional flour last longer.
Use of ground bark is also documented by the early explorers of North America, who wrote in their reports that they observed hectares of forests whose trees were almost entirely devoid of bark due to intensive use by the locals. The Adirondacks, a Canadian Algonquin tribe, were given their name by the Mohawks because of their custom of feeding on tree bark in emergency situations: Adirondack in the Mohawk language means ‘Tree Eaters’.
Although traditionally referred to as ‘bark meal’ or ‘pine meal’, this food can be obtained from several species of trees (such as elm, ash and birch) and is made from the phloem (inner bark), a complex of tissues typical of vascular plants with a triple function of transporting soluble compounds, acting as a reserve and supporting the plant. Phloem is generally the only edible part of the tree trunk, since the rest of the woody material is made up of cellulose and cannot be digested by humans.