The quality of an oak leaf inclusion in handmade paper depends substantially on how the leaf was prepared before embedding. Leaves that are too thick, too wet, too stiff, or poorly flattened create problems during sheet formation that no amount of technique can fully correct. Getting the leaf preparation right is the most reliable way to achieve clean, visually striking results.
Selecting Oak Leaves
Polish Quercus robur produces leaves with a distinctive deep-lobed outline that translates well as a silhouette in translucent paper. For botanical inclusion work, certain leaf characteristics are preferable:
Size and Shape
Medium-sized leaves — not so large that they extend to the edges of a typical A5-size mould, and not so small that the lobed shape is difficult to read — tend to produce the most satisfying results. The lobed outline of Quercus robur leaves (8–14 lobes on a typical mature leaf) creates a distinctive shadow pattern when the finished sheet is held to light.
Avoid leaves with major structural damage — large insect holes, tears, or significant brown edge burn — unless the damaged appearance is intentional. Minor imperfections are absorbed into the texture of the inclusion paper.
Freshness vs. Autumn Colouring
Both fresh green leaves and autumn-coloured leaves can be used, but they behave differently:
- Fresh green leaves (collected spring through summer) are more pliable and press flat more easily. They tend to retain a subtle green or brown tint once dried and embedded. The chlorophyll will not remain bright green in the finished paper.
- Autumn leaves in yellow, orange, and brown tones can carry their colour into the finished sheet, though the intensity fades considerably during processing. They are often more brittle and require careful handling during pressing.
Pressing Leaves
All leaves intended for inclusion should be pressed and dried before embedding. Fresh leaves contain substantial moisture that disrupts the forming fibre mat during sheet pulling, and their three-dimensional shape prevents even contact with the paper layer.
Basic Pressing Method
Place individual leaves between sheets of absorbent paper (blotting paper or plain newsprint without ink on the contact surfaces), then between boards with weight applied. Change the absorbent paper every 24 hours for the first few days if leaves are freshly collected. Leaves typically flatten and dry within one to two weeks depending on initial moisture content and ambient humidity.
In Poland's summer humidity, drying time may extend. Pressing in a heated room or near a heat source (not direct contact) can accelerate the process without damaging the leaf structure.
What Over-Pressed Leaves Do
Leaves pressed under excessive weight for extended periods can become extremely brittle — particularly autumn leaves and dry-season leaves already low in moisture. A leaf that shatters when you attempt to place it on the wet sheet is essentially unusable. If leaves are too brittle, briefly misting them with distilled water and allowing them to reabsorb a small amount of moisture before use can restore enough flexibility for handling.
Timing the Collection
Collecting leaves for a planned papermaking session several weeks in advance is common practice. In Poland, Quercus robur leaves reach full size by late May or June and remain available through October before autumn leaf fall. The most structurally sound leaves for pressing — full-sized, undamaged, not yet affected by autumn breakdown — are typically available from July through September.
Autumn collection in October also works well, particularly for leaves that have already begun to show colour change but have not become paper-dry and fragile on the tree.
Storing Pressed Leaves
Once dried and pressed, leaves can be stored between sheets of acid-free tissue or plain copy paper in a flat file, book, or portfolio. Avoid humid storage — leaves that reabsorb ambient moisture after pressing will cockle and require re-pressing. In Polish conditions, summer storage in an uncontrolled space may require a sealed container with silica gel sachets to maintain low humidity around stored pressed leaves.
Other Botanical Materials for Comparison
Oak leaves sit at the thicker end of the spectrum of botanical inclusions. For comparison: rose petals, viola petals, and thin grass blades are much easier to embed cleanly, requiring minimal preparation. Thick fern fronds and fresh maple leaves present similar challenges to oak leaves. Understanding where oak leaves fall in this spectrum helps set realistic expectations for the first attempts.