traditional tanbark canvas was made with 'cutch' aka catechu -- from the heartwood of an acacia species found in the Indian subcontinent.
You should be able to obtain cutch/cutch extract from a supplier of natural dyes, as well as the mordant(s) you'll need.
Get a good book on natural dyes and dying. This one, from Dover, is good: Natural Dyes and Home Dyeing.
This one, The Art and Craft of Natural Dyeing: Traditional Recipes for Modern Use, from the University of Tennessee Press is also supposed to be good.
[ 04-29-2003, 07:26 PM: Message edited by: Nicholas Carey ]
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