Fiber nettle

from Wikipedia, the free encyclopedia
Fiber nettle
Systematics
Order : Rose-like (rosales)
Family : Nettle family (Urticaceae)
Tribe : Urticeae
Genre : Nettles ( urtica )
Type : Great nettle ( Urtica dioica )
without rank: Fiber nettle
Scientific name
Urtica dioica convar. fibra
Poster calling for the collection of nettles for the production of yarn e.g. B. for bandages at the time of the First World War in Austria

The fiber nettle ( Urtica dioica L. convar. Fibra ) is a Konvarietät of stinging nettles ( Urtica dioica ). It was selected by Gustav Bredemann for a higher fiber content in breeding between 1927 and 1950 , but then fell into oblivion until it was rediscovered and cultivated further in the 1990s as part of the newly awakened interest in alternative fiber plants . Although it is not an established field crop, it is now being cultivated commercially.

description

The fiber nettle differs from the wild species in that it has significantly longer, straight stems, only minor branching, few stinging hairs and the shedding of the leaves in August, which facilitates the later utilization of the straw. It reaches heights of up to three meters.

Most important, however, is the greatly increased fiber content of 17 percent instead of 5 percent compared to the original shape, whereby the individual fibers also have larger cell walls.

history

Stinging nettles are well-known fiber plants, but the first attempts at commercial use were made in Germany in the 20s of the 18th century. In the 18th and 19th centuries it was used more intensively in Denmark, and high-quality textiles have been preserved from this period. More research was carried out in Germany in the 19th century, but the main obstacle was the lack of a practical method to separate the fibers from the rest of the plants. During the First World War , nettle fibers were so popular as a raw material in Germany that their growth had to be officially protected against premature harvesting and feeding.

Bauer und Laube carried out the first systematic selection of 170 wild nettles from all over Germany between 1918 and 1921. 12 of the nettles selected were further cultivated. Gustav Bredemann carried out further breeding and selection work between 1921 and 1950, first in Landsberg / Warthe (today: Gorzów), then at the Institute for Applied Botany at the University of Hamburg . Cultured fiber pods with fiber contents of up to 15 percent of the dry stem mass could be developed. Bredemann published a comprehensive work in 1959, "The Great Nettle", but his work was forgotten.

In the 1990s, plant populations preserved by Jens Dreyer were rediscovered by Bredemann's experiments at the Institute for Applied Botany in Hamburg and further researched and cultivated in cooperation with the Fiber Institute Bremen . Today they form the basis for various commercial uses, and in 2002 the Federal Plant Variety Office granted plant variety protection for the varieties “Wulfsdorf” and “Nesselgold” . The Hamburg breeding material is received from the Institute for Plant Culture and further processed in breeding.

Properties of the fiber

The fibers, which from a textile-technical point of view are usually referred to as nettle fibers and are classified as bast fibers, are on average 69.7 millimeters long (the length varies by 50.8 percent and in extreme cases can reach 215 millimeters) and 40 to 50 micrometers thick, oval to rounded polygonal or flat kidney-shaped in cross-section. In contrast to hemp and flax, the fibers are not arranged in groups, but are instead individually embedded in the sclerenchyme of the stem. The strongest and oldest fibers are in the outer part of the bark .

Since the fiber is naturally very soft, creamy-white in color and at the same time, due to its fineness (5 dtex), it is excellent for spinning, it is well suited for use as textile fiber. At the same time, with a specific tensile strength of 50 cN / tex (without roasting ) or 25 to 35 cN / tex (after roasting), it is a relatively strong fiber (cotton around 20 cN / tex). The nettle fiber consists of 86.5 percent cellulose.

Cultivation

As a plant widespread in temperate latitudes, the fiber nettle is suitable for cultivation outside of tropical, subtropical and polar regions. Above all, a good supply of water and nitrogen must be guaranteed. In addition, the plant values ​​loamy soils, too high a proportion of sand can impair growth. Since the plants are extremely vigorous and form dense stands, weed control is just as unnecessary as pest control, as the plant is naturally resistant to numerous pests.

To plant fibers nettles have cuttings proven in numerous trials. The plants cannot be harvested in the first year, after which it is possible to harvest six tons of stems per hectare for 10 to 15 years without replanting, which corresponds to around 900 kilograms of fibers with an average fiber content of 15 percent.

processing

The long-standing problem of obtaining the fiber from the stalks could only be solved with technical progress. After drying to around 15 percent water content, mostly water, mechanical fiber digestion or chemicals and selected bacteria are used to dissolve the fibers for roasting, with a subsequent treatment with enzymes . Ways that enable enzymes to completely dissolve the fiber are currently being explored.

The optimal processing of the fiber to the cloth has not yet been adequately researched. Currently, methods related to the processing of flax, hemp and ramie are mainly used. Difficulties are mainly caused by the very different lengths of the fibers and a lack of spinning spores.

use

After nettle cloth had not been produced anywhere in the world for decades and even after the rediscovery of the fiber nettle, major commercial applications initially failed to materialize, Stoffkontor Kranz AG in Lüchow resumed the production of fibers from fiber nettles in 1996. For the most part, the production was based on strains from the Bredemann breed. By the end of 2007, the cultivation area by contract farmers increased to 225 hectares of fiber nettles, more than 10 percent of the total fiber plant cultivation in Germany . The nettle fibers advertised as “Nettle” were used in home textiles and clothing, and their share in the fabric was ten to forty percent. In June 2009, Stoffkontor Kranz AG filed for bankruptcy. NFA Naturfaser AG has been supporting the development of fine nettle and hemp fibers since 2013 .

In 2005, the Brennels company planted around 30 hectares of fiber islands in the polder areas of the Netherlands.

See also

proof

  • J. Dreyer, G. Edom: Nettle. In: Robert Franck (ed.): Bast and other plant fibers , Cambridge / Boca Raton, 2005, pp. 331–343, ISBN 1855736845 / ISBN 0849325978 .
  • KU Heyland, H. Hanus, ER Keller: Oil fruits, fiber plants, medicinal plants and special crops , In: Handbuch des Pflanzenbaues , Vol. 4, pp. 307-308, ISBN 3800132036 .

Individual evidence

Most of the information in this article has been taken from the sources given under references; the following sources are also cited:

  1. ↑ Anonymous: On the nettles , in: dlz Agrarmagazin, 4/2008, pp. 170-173
  2. ↑ Eisenbahndirektion Mainz (ed.): Official Journal of the Royal Prussian and Grand Ducal Hessian Railway Directorate in Mainz from June 1, 1918, No. 26. Announcement No. 417, p. 191.
  3. ↑ a b c d Bredemann, Gustav and Garber, Kurt, 1959: The large nettle: Urtica dioica L. Research on its cultivation for fiber production. With an appendix on their use for medicinal and animal feed as well as technical purposes. Akademie-Verlag, Berlin, 137 pp., 7 plates, with 53 text a. Plate-Fig., 1 fiber sample u. 16 tab.
  4. ↑ Bundessortenamt: Descriptive variety list. Database query "Urtica" .
  5. ^ Institute for Plant Culture - Fasernesseln , accessed on April 28, 2009.
  6. ^ Paul-August Koch , Günther Satlow: Large Textile Lexicon: Specialized lexicon for the entire textile industry. Deutsche Verlags-Anstalt, Stuttgart 1966, 2 vol., Vol. L - Z, p. 109
  7. ↑ L. Bacci, S. Baronti, L. Angelini: Manuale Di Coltivazione e Prima Lavorazione Della Ginestra Per Uso Tessile ( Memento of the original from January 6, 2016 in the Internet Archive ) Info: The @1@ 2Template: Webachiv / IABot / www.lammatest.rete.toscana.it archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. (PDF; 733 kB) . on page 29
  8. ↑ History of Stoffkontor Kranz AG - 300 soccer fields new living space. In: Nettle World. Stoffkontor Kranz AG, January 2008, accessed on May 20, 2009 .
  9. ↑ Nettleworld.com: letter of provisional administrator June 25, 2009 , accessed on 11 September, 2009.
  10. ↑ Website "NFA-Naturfaser AG"
  11. ↑ "Brennels" website  ( page no longer available , search in web archives )  Info: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice. → German → Brennels /@1@ 2Template: Dead Link / www.brennels.nl  
  12. ↑ Eckard Grundmann, 2007: Attempts to cultivate the fiber nettle ecologically. In: Organic fiber plants. Cultivation - processing - market. Conference proceedings, June 19, 2007, Kassel. IBDF series of publications, Volume 20, Verlag Lebendige Erde, p. 44. ISBN 978-3-921536-68-1 .

Web links

  • The fiber nettle (history, cultivation, fiber, use - research focus on fiber plants in the Department of Plant Ecology and Crop Biology, University of Hamburg)