The inner barks of certain plants, most commonly of the mulberry family (Moraceae), are used in tapamaking. Breadfruit (Artocarpus sp.), fig (Ficus sp.), and mamaki (Pipturus spp.) are also used. Paper mulberry trees require cultivation and careful tending. When the trees are one or two years old, the branches or trunk are cut and the bark is split and removed. The bark strips are soaked in water overnight or immediately placed with the inside up to flatten. The outer bark is removed from the inner bark. Scraping with shells, coral, a knife, or, more recently, a piece of corrugated iron roofing removes any remaining outer bark fragments. Clean and well-scraped inner bark produces a better quality cloth. The bark strips are often soaked in seawater or fresh water for a day or more and sometimes wrapped in leaves and left to ferment for several days. Soaking removes impurities and softens the compacted fiber bundle.
At this point in the production process, inner bark strips are spread out and beaten using a hard tool, usually made of wood and less commonly of stone, against an anvil. Regional differences are visible in the selection of beaters displayed here. The quality of tapa sheets depends on the beating process. The fiber strip is folded and layered, and then beaten with consecutively more finely grooved sides of the beater. Several bark strips can be beaten together to achieve the desired shape and thickness. Strength is achieved in the beating process through the folding and layering of the long bark fibers. In some regions, preliminary beating is followed by additional soaking in water and bleaching in the sun.
Large sheets are made by felting or pasting. Felting requires additional beating and water to aid in meshing the fibers. The beaten strips, which are either positioned on top of each other or side by side and slightly overlapping, are felted by beating the layers together. Pasting requires a starch adhesive such as arrowroot and involves pasting together the edges of two sheets. Long or wide cloths (as illustrated in the photograph above) can be made by this technique and may require several tapamakers. Openings or holes that develop during the beating can be closed by pulling over, felting, folding, or patching.