ENHS Nature Trails November 2005 Article 3

Pressing and Mounting Fall Leaves
By David Wagner

The critical part of the process is to dry the leaves quickly at the same time they are being pressed. I use a plant press made from boards, ropes, and newspapers. Cut two 9" X 12" sheets of 3/8" plywood for the end boards. The leaves are pressed between newspapers bound in these press boards.

First set a press board on the table and place several newspaper sheets folded together on it. The idea is to be able to handle three or four newspaper sheets by the folded edge. The Oregon Daily Emerald is a perfect 9 X12 inches when folded; other papers (Register Guard) will have to be trimmed unless you use boards large enough to accommodate them. Do use a whole section for each layer.

Arrange leaves on this newspaper so the leaves do not overlap. Put another newspaper section on top of the leaves. Build up a stack of alternating layers of leaves and newspapers. Five to ten layers of leaves are a good number to handle at one time. On the top goes the second press board. The whole collection is now bundled tightly with rope.

How well the leaves are pressed is determined by how tightly the press bundle is tied. Here's a trick that helps: Place on the top of the press a piece of foam (sponge) cut to 9 X12 inches and at least one inch thick. If the foam is compressed while tying, it keeps excellent pressure on the whole stack. I put a knee on the press, between the ropes, while tying up the press.

Pressing is only half of the process; the other half is drying. This is done by changing the newspapers. The newspapers draw moisture out of the leaves. After only a few hours, the newspapers have drawn about as much moisture out of the leaves as they can absorb quickly. It is time to replace the newspapers in the press with dry newspapers.

Open the press, set aside the foam (if you are using some), and put the top press board on the right. Put a dry newspaper on this board. Take the top, moist newspaper off the stack in the press and set it to the left side. Transfer the leaves from the press stack to the dry newspaper. Put a dry newspaper on the transferred leaves. Then remove the next moist newspaper from the press stack and set that aside. Repeat the leaf transfer process until all the leaves in the press have been transferred to the new stack made up of layers of leaves and dry newspapers. Replace the foam and tighten the press.

If the newspapers are changed in the press at least twice daily, most leaves will be dry in only a few days. To test for dryness, hold a leaf against your lips. If it feels like a piece of paper, it is dry. If it feels cool, it means there is still moisture in it that is drawing heat from your lips, and a few more changes of dry newspaper in the press are needed before mounting.

When drying is completed, arrange the leaves on a sheet of heavy mounting paper or card the way you like. Do the arranging before glue is applied so that the leaves can be moved around until the arrangement is satisfactory.

To mount leaves tightly on mounting paper, I like to fix the glue under pressure. A white glue like Elmer's works very well. First, use a two inch paint brush to spread a thin layer of glue on a sheet of glass, formica, metal or other smooth, hard surface. Thin with a few drops of water to help spread it out. Experience will instruct how thick of a layer of glue is best and how much water to use. Start with a thin layer of thinned glue.

Pick up a leaf by the base with a pair of sharp tipped tweezers (forceps) and set the leaf carefully on the thin layer of glue. Poke the leaf down onto the glue plate with a fingertip to be sure the underside of the leaf gets an even coating of glue all over.

Again, using forceps, pick up the leaf by the base next to the leaf stalk. Lift carefully so the glue stays on the underside of the leaf. Set the leaf down on the sheet of mounting paper. If the glue seems to be heavily applied and tends to squeeze out from the side of the leaf, blot by pressing at the edges with a paper towel or bath tissue. Set the sheet with freshly glued leaf on a section of newspaper. Then, carefully lay a piece of plastic wrap over the leaf. This keeps the glue from sticking to anything except the mounting sheet. Set a newspaper on top of this, then a press board, then a weight--I like a two gallon bucket filled with gravel.

The next mounted leaf is added to this stack by lifting off the weight and board, then adding the sheet with leaf placed on top of the newspaper. Add another piece of plastic wrap, another newspaper, and then replace the board and weight. Mounting continues in this fashion and ensures that the glue will have its moisture drawn through the mounting sheet into the newspaper below. The plastic wrap keeps the leaf mount from sticking to the newspaper above it in the stack.

This stack needs to be left alone for a couple of hours; overnight is ideal. By this time the plastic wrap will have set up in the white glue. The sheets are removed and set in the open to finish drying. If the paper curls up at this stage it means either the mounting sheet was not heavy enough or too much glue was used. After final drying, the mounted leaves are suitable for display or making rubbings.

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