Analysis of the bast used by the Iceman as binding material

Abstract

The bark of dicotyledenous plants is made up of phloem (bast) and the hard bark (Fig. 1A). Phloem is the living bark. It is the term applied to the secondary tissue that is formed from the cambium layer in dicotyledenous plants. It is comprized of conducting elements, parenchyma and sclerenchyma cells, the bast or phloem fibres. Phloem fibres and parenchyma are formed alternately by the cambium. This explains the accumulation of phloem fibres in the tissue, known as hard phloem, which is followed by layers of conducting elements and parenchyma, the soft bark. The bundles of phloem fibres have a protective and supporting function under mechanical load and among other things are responsible for the ability of plants to return to the vertical after yielding to lateral pressure. These fibres are accordingly soft, elastic and have a very high breaking strength. That makes them ideal for making yarns and durable cords. These properties of phloem fibres or bast were known to the Neolithic man.