Smoke Tree (Cotinus coggygria)

Before the last leaves dropped, I managed to photograph my Smoke Tree & I thought I’d write an entry about this interesting & historic dye plant. Formerly Rhus cotinus & now Cotinus coggygria, the Smoke Tree is also known as the Wig Tree & Venetian Sumac. Its other name is Young Fustic, to distinguish it from Old Fustic, which was a later introduction from central America & is what we now know as Fustic. The word “fustic” apparently came from the Arabic “fustug”, meaning “bush”, & describes the growth habit of Cotinus coggygria. It is native to southern & central Europe & is also found in Turkey. It was widely introduced elsewhere & is a popular ornamental shrub in parks & gardens, particularly the purple-leaved varieties. 

From the Middle Ages onwards, the heartwood & leafy branches of Young Fustic were widely used in Europe, especially Italy, for dyeing silk & wool, often in combination with other yellows, such as weld, as the yellow shade from Young Fustic tends to have a reddish hue. In addition, it was used with many other dyes to create a variety of colours & was not only versatile but also more economical than some other yellow dyes, as the heartwood has considerable tinctorial power. Its main disadvantage would seem to be its relatively poor fastness when compared with dyes such as weld, as most shades from Young Fustic tend to change to russet over time. In the past it was clearly a significant dye, as tests on many historical textiles from various parts of the world show evidence of Young Fustic, often in combination with other dyes to create compound colours. It is rich in tannin, so when used with iron it gave deep, full shades. Young Fustic continued to be of economic importance until the 19th century & was used until very recently in country districts of Albania.

The dyestuff we now know commonly as “Fustic” comes from the heartwood of Morus tinctoria or Chlorophora tinctoria, a member of the mulberry family, which grows in central America & is one of the few natural dyestuffs that continue to be used commercially. Once the sea routes to the Americas were established, Fustic was imported into Europe, where it was called “Old Fustic” in English & “palo fustete” in Spanish, indicating that the similarities in both appearance & dyeing properties between “Young Fustic” & “Old Fustic” had been recognised. Indeed, in 16th century Britain it was often difficult to tell whether the term “fustick” referred to “Young” or “Old” fustic. Sometimes both “Young” & “Old” fustics were used in combination to create an orangey shade. For further fascinating information about fustic, & virtually every other dye source, I strongly recommend Dominique Cardon’s “Natural Dyes”. This is a weighty volume, & not cheap, but it is a highly readable scholarly work that provides a most valuable resource for those seeking information on dyes & dyeing from earliest times to the present day.

More Dye Extracts

I’ve been trying out two more extracts, rhubarb root & cutch waste. Rhubarb root is a useful & versatile dye, so I was pleased to see that it is available in extract form from Pure Tinctoria. Among the other extracts on their list I came across “Cutch Waste”, which intrigued me. Cutch, rather than cutch waste, gives rich browns on all fibres &, like rhubarb root, can be used without a mordant. Cutch is one of the few dyes that has been available in extract form for very many years. In fact, I have never come across cutch in any other form. It is produced by simmering the heartwood of Acacia catechu (native to India & SE Asia) in water, then reducing & evaporating the liquid until it becomes very thick. It is then poured onto matting & left to dry & harden into a solid mass, which is cut into chunks, then powdered. Just where the cutch waste comes from, I’m afraid I don’t know. Another puzzle to be solved!

I first came across rhubarb root as a dye some years ago in an article in the Weaver’s Journal. The article was about Tibetan carpet weavers working in Nepal, for whom rhubarb is a vital dye plant. The leaves contain oxalic acid, which they use as a kind of mordant or base for other colours. They also add rhubarb leaves to organic indigo dye vats to assist fermentation. The rhubarb root is used for yellows, rusts & as an addition to brighten madder dye baths. The article suggested alum might be difficult to obtain in Nepal, unless from plant sources such as the leaves of plants that absorb aluminium from the ground, & therefore most dyes were used without a mordant. So I experimented widely with rhubarb root on unmordanted fibres, as it is so useful to have a source of yellow that doesn’t require a mordant, especially in order to obtain a green when overdyed with indigo. However, I have to say that, although rhubarb root dyes wool & silk excellently, it is less effective on cellulose fibres.

 I tested both these extracts on wool without a mordant & with an alum mordant. Both fixed well without a mordant. The rhubarb root produces a clearer yellow without a mordant & a more mustard shade on an alum mordant. The cutch waste shade is an attractive soft greyish green, (more green than grey, however) very useful as a contrast to more vivid colours. Unfortunately, the photo doesn’t really do justice to the colours.

Rather foolishly, I didn’t try out any colour modifiers with these extracts. I don’t know why, as I usually do a full set of tests. Rhubarb root in its plant form reacts well to modifiers. It gives moss green with iron, a brownish (taupe?) shade with copper & shades ranging from red-brown to red with an alkali such as washing soda. Truly a versatile dye. (More details on using modifiers in the entry about dahlias.) So now I must do these tests with the rhubarb root extract, to see if it reacts in the same way.

In my experience, not all extract dyes respond as well to colour modifiers as their plant counterparts. I think this is because some extracts are treated during the production process to reduce their sensitivity to changes in pH values & thus make the colours more stable if washed, or otherwise treated, in a non-neutral medium. I routinely wash naturally dyed fibres in dishwashing liquid & I have yet to find a dishwashing liquid that is not pH neutral when in solution. Some extracts are also probably treated during manufacture to remove some of the less desirable pigments. This would explain why madder extracts vary so much from one production company to another. The more recent Earthues madder extract gives a wonderful clear rich red, while their earlier madder extract was much more orange in tone. Some other madder extracts also produce more orange/coral tones, which can be made pinker/redder in tone by using a washing soda after-soak – but NO heat particularly if dyeing wool.

More about extracts when I’ve done some more tests.

Natural Dye Extracts

Although nothing can quite compare with growing one’s own dye plants & being able to complete the dyeing process from start to finish using home-grown materials, I am very enthusiastic about the natural dye extracts now readily available on the market. These extracts are extremely versatile & easy to use & all the classic, traditional dyes are now available in extract form.They dissolve in water, so there is no need to simmer the dye materials to extract the colour, and 2 or more extracts can be mixed together to create further shades. Although they may appear expensive at first glance, in fact they are good value as very little is needed for full colours.  I have written about extract dyes in “Colours from Nature”, my latest book, which gives full details for their use. More recently I have been trying out some new extracts.

In the photo above, the upper 2 samples have been dyed with “Sorghum” extract (the lower of these 2 samples is from the exhaust dyebath) & the lowest sample with “Teal” extract. These are both available from DT Craft & Design.

Sorghum, or Guinea Corn, Sorghum vulgare, is an interesting source of dye colour, as well as being a foodstuff. Native to parts of Africa & Asia, Guinea corn was also introduced elsewhere, including Europe & America. Although it is not well-known in Europe as a dyestuff, it was used to dye wool in Egypt & in Sudan to dye reeds & grasses for matting. It was an important dyestuff for both textiles & leather in other parts of Africa & was also used in Japan & China. Sorghum has good fastness properties. The parts used are the stalks, leaf sheaths & corn husks. On wool, sorghum extract gives colours similar to the rust shades from madder. I tried it both without a mordant & with an alum mordant & found the colours were virtually identical, so a mordant may not be necessary.

“Teal” extract is intriguing, especially as so far I have not managed to discover the plant sources from which the colour is made. I expect this is a trade secret. But it gives a beautiful green/blue/turquoise shade, which is a rare colour from natural dyes &, in my experience, only possible when indigo is used in combination with at least 1 other dye.

More about extract dyes later.

WOAD AGAIN

Just as I’d finished writing about my latest woad-dyeing session, I received 2 emails with queries about woad. A lady wanted to know how to use the woad balls she’d purchased & a gentleman wanted to know more about Watchet blue.

As far as using woad balls is concerned, I think the best way to do this would be to follow the method I gave in my entry on Woad Dyeing in November. But before pouring hot water on the woad balls, crumble them into small pieces. Then pour on the hot water & continue as for fresh leaves, perhaps returning the leaves to the vat after the whisking process & leaving them in during dyeing. If you don’t add the leaves to the vat, don’t throw them away, however, as it may be possible to re-use them for paler shades. This is the method I used when dyeing with indigo balls from Nigeria & it seemed to work well.

Watchet blue would seem to be connected with Watchet in Somerset, where cloth was manufactured in mediaeval times. Woad was grown in Somerset, particularly around Glastonbury, but I don’t know whether Watchet had a connection with woad dyeing.  From the 12th century, “watchet” was used to describe a particular shade of blue from woad, probably a mid to light shade. Watchet blue is mentioned by Chaucer & Shakespeare & apparently both Mary Queen of Scots & Charles 1st wore items of Watchet blue for their executions. (Mary wore blue stockings & Charles wore a blue knitted waistcoat.) The name might also be connected with the fact that small boats called “Watchet flatties” were traditionally painted Watchet blue. John Edmonds, in his book on Medieval Textile Dyeing, devotes a paragraph to Watchet Blue.

What’s in a name? Indigo or Woad

While at the Oxford Guild, a lady asked me about the difference between indigo and woad. This is a good question as the difference is really one of name rather than dye, as the blue dye in woad is the same as the blue dye in indigo, so woad is just another source of indigo-blue dye. Woad was, and still is, the native European source of indigo blue dye. The name “indigo” is usually used to refer to species of Indigofera, although it may also refer to one of the many other sources of indigo blue dye, such as Polygonum tinctorium from Japan, Strobilanthes flaccidifolius from China or Lonchocarpus cyanescens from Nigeria. In fact, I suppose the term “indigo” tends to refer to all sources of indigo blue dye, except for the blue dye from woad. This is confusing as the blue colouring matter in woad is the same as the blue colouring matter in “indigo”, but the dye is much less concentrated in woad leaves, which is why “indigo” eventually largely replaced woad in Europe. It would make things clearer if we referred to woad-indigo to distinguish it from indigo-blue from other sources. In England, until the 1930s a law demanded that some woad had to be used in the indigo blue dyeing of policemen’s uniforms, presumably to preserve the tradition of woad dyeing & to protect the livelihoods of woad farmers.

Today, the farming of woad on a commercial scale has been started again, largely through the efforts of one farmer in Norfolk, Ian Howard, who has made a valuable contribution towards the revival of one of our traditional dyeing techniques. For more information, click onto the link to Ian’s website.