For the past few years my friend Carol and I have been making paper out of willow bark over Easter weekend. We take the whole weekend and eat peeps and hot cross buns while we work. This year, however, the cool weather here through early spring meant that the willow trees that we usually harvest hadn't begun to sprout or show any signs of rising sap, causing us to delay gathering bark until April. So this year Easter weekend paper became first weekend of June paper, and our supply of willow was about half of what we usually have. Hot cross buns and peeps gave way to a leisurely walk to a local restaurant for burritos.
Last week we began soaking the dried bark, which we had peeled back in April, in preparation for cooking it on Friday. Since we had a smaller amount, we had decided to use both the bark and the inner bark (the bast fiber); this decision also saved us the work of peeling the inner bark from the outer bark. On Thursday I simmered the cut up bark in water with baking soda for around 7 hours. Cooking willow is interesting: the water turns a beautiful maroon color, and the smell is fresh, almost like newly-mown hay.
Here's a page from my studio notebook. At this point we had discovered that the ketene dimer sizing that we usually use was missing from the paper studio, and there was none to be had in Asheville. We noticed some methylcellulose solution in a refrigerator in the studio, so we Googled methylcellulose as a sizing for paper and learned that it could be used; but we were unable to find details regarding how much to use per gallon of pulp, nor could we uncover the "different properties" that the article alluded to when methylcellulose was used instead of the preferred ketene dimer sizing.
We used a small amount of our pulp to test different amounts of sizing, finally deciding to quadruple the amount we started out with when our initial test showed quite a bit of bleeding when we tested the paper with water media.
The image below shows a sample page, half of which is pasted into the notebook with test results. To its left is a half sheet of the finished paper. We mixed the willow pulp with some abaca (manilla hemp) to give the paper strength. Willow fiber is relatively short and therefore weak, whereas abaca has relatively long fibers and good strength. We were pleased with the feel of the paper and especially with its beautiful pinkish color. The dark specks are from the outer bark. They're so small and flat that they don't cause a problem with writing or painting on the paper, although they might interfere with letterpress printing on it. We made around 75 sheets on a smallish rectangular mould so that the sheets could be folded in half and sewn into books that have three deckled edges. The other 26 sheets are around 12 x 18", good for relief prints or silkscreen.
We're already planning our next raid on willow trees. No waiting for spring next year; we plan to have it all gathered and peeled within the next few weeks. Then next Easter week we can pull out our supply of dried willow, soak it for a few days, and have a proper Easter week papermaking. We're thinking of hand-beating next year and of mixing the willow with hand-beaten kozo for strength.