Bryant wrote today's entry:
A big thank you to Anne Elliott (aka annkelliott@Flickr) for today's image of Letharia vulpina (commonly called wolf lichen), the last image in the series on plant colour. Letharia vulpina is commonly found in dry coniferous forests across western North America, Eurasia and northern Africa. People have used this particular lichen in a number of different ways over the course of history. The yellow pigment comes from a compound known as vulpinic acid. Vulpinic acid is known to be poisonous to mammals; the source of the common name "wolf lichen" comes from its former use in Europe as a substance for killing wolves. In North America, the species has been used by the Achomawi to make their arrows more lethal for hunting.
Letharia vulpina, with its striking colour, was perhaps more widely used for making dyes and paints (a practice that continues today, though less often). Records show historical use to make dye for woollens in Scandinavia. Also, many North American First Nations made or make use of Letharia vulpina as well. The Klamath, Cheyenne, Karuk, and Yurok nations soaked (or soak) porcupine quills and other materials in a solution of the extracted yellow pigment, with the coloured objects later to be woven into baskets. The Tlingit used/use a solution made from Letharia vulpina to dye fibres for Chilkat blankets. The Apache people used a decoction of Letharia vulpina as a paint, which they made crosses on their feet when moving through enemy territory, with the belief that it made them undetectable. Coastal tribes that were located outside its native range often traded for Letharia vulpina, making it an important lichen economically as well. To read more about traditional uses of lichens, see Ethnolichenology of the World.
The act of temporarily and permanently decorating our bodies with colour is a global phenomenon that is deeply rooted in our fascination/appreciation with plant and other pigments. The role that this cultural fascination has played in the course of history is pretty remarkable. David Lee reminds us that, "...using plant extracts to dye skin and fabric was a major technological accomplishment". Unlike food or most traditional medicine, dyes are usually produced by combining a decoction with other materials that alter the chemical structure, making them bright and permanent. Soon after these techniques were developed, plant pigments and other natural dyes began to be exploited to add vibrance and colour to the people of these early civilizations. Plant pigments helped make warriors appear more intimidating, royalty seem more royal, and added beauty to those who could afford it. Some common historical plant dyes came from Rubia tinctorum (madder), Indigofera tinctoria (indigo), and Caesalpina echinata (Brazilwood). These plants and the pigments they produced were highly prized commodities that drove much of the early trade between Asia, North Africa and Europe. With increased trade also came colonization, where "the colonies provided the raw materials feeding the industrial Revolution in Europe, including fibre and dyes for the great textile mills" (Lee). In the mid-19th century, two students at the school of Justus von Liebig in Germany made discoveries that developed the artificial production of dyes. One of these students, August Kekule von Stradonitz contributed a theory (derived from these discoveries) that played a major part in the foundation of organic chemistry!