The Walnut Tree

    Walnuts have been recognized as one of the oldest tree foods known to man, dating back to about 7000 B.C. Considered food for the gods in the early days of Rome, walnuts were named "Juglans regia" in honor of Jupiter. The black walnut is a hardwood tree that frequently grows to a height of one hundred feet with a trunk diameter of up to six feet. The dark, rough bark, is divided into squarish units. The leaves are alternate, one to two feet long, and have fifteen to twenty three leaflets that are light green in color. Today, they are commonly called "English" walnuts, in reference to the English merchant marines whose ships once transported the product for trade to ports around the world. Also known as the Persian Walnut (attributed to the region of it’s origin), the Black Walnut grows in many parts of North America, as well as throughout Europe.

    When used for making dyes and ink the benefits of walnut are twofold. The Walnut tree produces a substance known as juglone (5-hydroxy-alpha-napthaquinone) which is highly toxic to many other plants and some animals. Awareness of black walnut toxicity dates back at least to Roman times, when Pliny noted a poisoning effect of walnut trees on "all" plants. Juglone is the source of the dark color in walnut hulls. Initially colorless, juglone oxidizes over time to a very dark brown. In addition to the juglone, the husk of walnuts, like many plants, contain tannins. Ionic iron combines with tannins to produce iron tannate compounds, which are black, and the basis of gall inks. The juice from walnut husks was used extensively throughout history as a dye, it is colorfast, lightfast and virtually no solvent removes it from skin.

    Some of the first skills that a medieval scribe would learn were how to prepare his ink and paint, for without basic tools of the craft   no art can be created.  The chemistry of art was passed down through generations of Master's to their apprentices and we are left only very late medieval texts to document much of the process.  I have had an exceedingly difficult time in attempting to document this solution to period as an ink.  After conversations with several artists, art historians, and reenactors I am assured that this ink/stain/dye was used in the Middle Ages for a multitude of purposes.   However, I have yet to turn up a single recorded recipe, and few of my books of manuscript pages that exhibit the characteristics of walnut ink have bothered to note the type of ink that was used.   Several period recipes which use various tree  products (like bark, fruit and galls) and rely on the same principals as the walnut ink production can be found.  It is not far reaching to believe that walnuts were used for the same purpose.  With   the ancient origins of the walnut tree and it’s widespread availability,   producing a solution from walnuts for it’s many abundant uses may simply have been a part of everyday life.

1. Asplund, Randy; Conversations with the noted artist and art historian throughout October 2000
2.  Boucher, E.; "The Ink Compendium", http://www.geocities.com:0080/CollegePark/Library/2036/ink.html ,1998
3. California Walnut Board, www.walnut.org, 2000
4. Carvalho, David; "Four Centuries of Ink", The Gutenburg Project, Champaign, 1998
5. Dun, Kevin; "From Caveman to Chemist", http://cator.hsc.edu/~kmd/caveman/projects/dye/, 1996-2000
6. Hogue, Paul; "Real Black Walnut Stain", Primitive Archer Magazine, 2000
7. "Molecular Expressions Website", Florida State University, http://micro.magnet.fsu.edu/trees/pages/blackwalnut.html, 2000
8. West Virginia University AHRD Webpage, http://www.wvu.edu/~agexten/hortcult/fruits/blkwalnt.htm, 2000
9. http://medievalwriting.50megs.com/tools/ink.htm

Walnut Dye

The use of colored wool, was a great advance in the ability of textiles to the denote wealth and status of it’s wearer. But the larger advance came as a consequence of the ease with which wool can be dyed. The first discovery of such stains were probably accidental. Nuts and berries collected for food came in contact with clothing and stained them. Most of these colors washed out, particularly with soap and water. But some of the stains proved colorfast and over time plant materials were likely collected for dyeing rather than eating.  Black walnut dye is both colorfast and lightfast.

The juglone based walnut solution, can also be used to stain wood a lovely shade of deep golden brown, which I proved by accident using a wooden spoon to stir the solution as it boiled. Paul Hogue offered this method for staining arrow shafts with walnut in Primitive Archer Magazine:

"Cut an opening halfway into a green walnut, and if it is ready, the inside will be black and juicy. The nut in the center is about the size of a quarter to a half-dollar. You can pluck the nut out if it’s in your way or leave it. You'll want to put on some thin, rubber gloves, because, like I said, it’s real stain. Next, just wrap the whole walnut around your arrow shaft (or whatever you want to stain) and run it up and down. Then with a clean rag, wipe off the excess juice and particles from the wood. If you decide you want the stain darker, just do it again in a few minutes."