Bast (plant)

Longitudinal section through xylem (far right) and phloem (middle to middle right). The small circles in the phloem are the sieve zones of the sieve tube cells , the solid zones in the phloem contain the storage tissue cells ( parenchymatic cells).

Cross-section through a five-year-old pine trunk

The bast is the living tissue under the bark of trees and other woody plants (secondary phloem ).

function

This bast tissue transports nutrients dissolved in water - sucrose (as a transport form of glucose), ions , secondary plant substances - from the crown to the roots; seldom also in the opposite direction (the transport from the roots to the crown usually takes place via the sapwood ).

Components

Bast consists of sieve tube cells (which form the sieve tubes ), escort cells , bast fibers and storage cells . That is why the bast tissue of a living tree is moist and very soft in relation to the wood and bark, but also always tough and very resistant.

The phloem fibers are flexible, long cells on which softer fibers are built (e.g. in flax or hemp ). The corked bast forms the protective layer for the stem and roots of plants.

history

Bast fibers from trees (especially oak , linden , willow and elm ) were already used in the Mesolithic for coarse braids, nets , cords, ropes and textiles .

The raw materials treated by roasting , a process for obtaining the resistant fibers, were found processed in the circumalpine wetland settlements of the Neolithic . Oak bast in particular has been handed down from the Cortaillod culture and the Egolzwiler culture , and linden bast in particular from corded ceramics .

Web links

• Bast, rushes, nettles: textile material from the Stone Age poster series, special exhibition of the Dithmarschen Museum of Archeology and Ecology

Individual evidence

1. ↑ A. Rast: The processing of bast. In: The first farmers. Pile construction finds in Europe. Research reports on the exhibition in the Swiss National Museum. Volume 1, Zurich 1990, pp. 119-121.
2. ↑ A. Rast-Eicher: The textiles. In: J. Schibler et al. (Ed.): Economy and ecology of Neolithic and Bronze Age bank settlements on Lake Zurich. Volume A, Zurich 1997, pp. 300-328.
3. ↑ Jens Lüning: Stone Age farmers in Germany. Habelt, Bonn 2000, p. 100.
4. ^ Johannes Hoops, Heinrich Beck, Dieter Geuenich, Heiko Steuer: Wald. In: Reallexikon der Germanischen Altertumskunde. Volume 33, pp. 114-115.
5. ^ Anne Reichert : Processing and processing of linden bast . AEAS (Working Group Experimental Archeology in Switzerland), Anzeiger 2005, pp. 5–7 ( PDF ( Memento of the original dated August 12, 2014 in the Internet Archive ) Info: The archive link has been inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. )