Blackberry
The blackberry has been a part of what is now American culture for hundreds of years. Wild blackberries are said to symbolize separation as they were planted to keep animals and people out of areas. The brambles and thorns were a natural deterrent, and when planted close together, they created a wall of thorns. This was also useful as the Indians were able to use much of the blackberry bush in daily life. The berries were not only used as food. They made a dark purple dye and ink.
One recipe calls for collecting the juice of half a cup of crushed blackberries, then adding a half teaspoon of vinegar and salt to preserve it. Indians most likely would have used a recipe similar to this but would have substituted soot or ash as the preservative. This ink is made in small batches as it will sour easily.
Pokeberry
According to earthcaretaker.com, pokeweed or pokeberry gets its name from a pre-Columbian American word meaning "plant used for red or yellow dye." The pokeberry is a very common weed that is found all over America and was used by Indians as food and for making dye and ink. The pokeberry dye is not colorfast and fades quickly after washing, but has lasted many years as ink. The berries would have been crushed and mixed with soot or cinders to make a thicker paste to be used as ink. The berries are poisonous as they cause digestive problems such as vomiting and diarrhea.
Elderberry
Elderberry is another plant that grows readily all through America. Some consider it a weed; however, many people still use it for making jelly, wine, teas, dye and ink. The Indians used elderberry for all of these purposes as well. The ink from an elderberry plant was made by crushing the berries and either cooking the juice down to make it thicker or adding ash or cinder.
Elderberry makes a deep reddish purple ink and dye. Turkey feathers were often used as quills for writing with elderberry ink or simply dipping a finger in the dye and making symbols on paper, animal skin or rocks.