Flax and weld: archaeobotanical records from Mutina (Emilia Romagna, Northern Italy), dated to the Imperial Age, first half 1st century a.d.

In the city centre of Modena (Emilia Romagna, Northern Italy) a noteworthy amount of carpological remains attributable to flax and weld came to light dated to the Imperial Age (first half 1st century a.d.). Flax remains, i.e. capsules and extremely small seeds, suggest the presence of either immature seeds and fruits of cultivated flax (Linum usitatissimum L.) or of a wild flax species (Linum bienne Mill.). The quantity of these remains along with the co-presence of seeds of Reseda luteola, an important dye plant, leads to the hypothesis of the cultivation of both flax and weld for textile manufacturing purposes, which are attested as important in the economy of the Roman period.     

Flax in Sweden: the archaeobotanical, archaeological and historical evidence

The earliest recorded evidence of flax being cultivated in Sweden is from the end of the Bronze Age/beginning of the Iron Age. Later, from ca. a.d. 1100 and onwards, flax became an economically important plant in the country, and during the 12th to 16th centuries there was a substantial increase in the Swedish export of linen to other parts of Europe. Alongside its extensive cultivation, a set of cultural traditions and rituals was eventually built up around flax. The objective of this article is to draw an outline of the history of flax cultivation in Sweden and to present the relevant prehistoric and historic source material. A point of discussion will be the different roles that fibre flax and oil flax played over a long period of time and the problem of seed corn import for the development of domestic fibre flax in the country. The study is based on the prehistoric archaeobotanical record, mainly charred seeds from the Swedish Iron Age (ca. 500 b.c.–a.d. 1050), the archaeological record, documentary evidence and folklore.     

Flax in Neolithic and Bronze Age Greece: archaeobotanical evidence

This paper presents an overview of archaeobotanical finds of Linum usitatissimum from Neolithic and Bronze Age Greece, bringing together published records of this plant as well as some recently retrieved, unpublished finds. In addition, charred flax seed concentrations from five prehistoric sites from the region of Macedonia in northern Greece, are examined in detail. The Neolithic sites are Makriyalos, Mandalo, Arkadikos, Dikili Tash, dated to the Late and Final Neolithic and Archondiko, dated to the end of the Early Bronze Age. Archaeobotanical composition and contextual information are used in order to explore the cultivation and potential uses of flax at each site. By the 5th millennium b.c. a flax weed flora had probably developed in the region. The use of flax seed for oil extraction and flax stems for flax fibre preparation can only be speculated upon and these uses are discussed within the context of other archaeological finds related to plant oil production and weaving. It is also possible that flax may have been used for medicinal purposes. Despite a striking paucity in archaeobotanical remains from southern Greece, textual evidence available from the Mycenean palace archives in Linear B clearly documents the cultivation of flax and flax fibre production.     

Improving retting of fibre through genetic modification of flax to express pectinases

Flax (Linum usitatissimum L.) is a raw material used for important industrial products. Linen has very high quality textile properties, such as its strength, water absorption, comfort and feel. However, it occupies less than 1% of the total textile market. The major reason for this is the long and difficult retting process by which linen fibres are obtained. In retting, bast fibre bundles are separated from the core, the epidermis and the cuticle. This is accomplished by the cleavage of pectins and hemicellulose in the flax cell wall, a process mainly carried out by plant pathogens like filamentous fungi. The remaining bast fibres are mainly composed of cellulose and lignin. The aim of this study was to generate plants that could be retted more efficiently. To accomplish this, we employed the novel approach of transgenic flax plant generation with increased polygalacturonase (PGI ) and rhamnogalacturonase (RHA) activities. The constitutive expression of Aspergillus aculeatus genes resulted in a significant reduction in the pectin content in tissue-cultured and field-grown plants. This pectin content reduction was accompanied by a significantly higher (more than 2-fold) retting efficiency of the transgenic plant fibres as measured by a modified Fried’s test. No alteration in the lignin or cellulose content was observed in the transgenic plants relative to the control. This indicates that the over-expression of the two enzymes does not affect flax fibre composition. The growth rate and soluble sugar and starch contents were in the range of the control levels. It is interesting to note that the RHA and PGI plants showed higher resistance to Fusarium culmorum and F. oxysporum attack, which correlates with the increased phenolic acid level. In this report, we demonstrate for the first time that over-expression of the A. aculeatus genes results in flax plants more readily usable for fibre production. The biochemical parameters of the cell wall components indicated that the fibre quality remains similar to that of wild-type plants, which is an important pre-requisite for industrial applications. Magdalena Musialak and Magdalena Wróbel-Kwiatkowska participated equally in the preparation of this paper     

Production of polysaccharide-degrading enzymes by saprophytic fungi from glyphosate-treated flax and their involvement in retting

The fungi present on glyphosate-treated flax plants were isolated. Cladosporium herbarum, Epicoccum nigrum, Botrytis cinerea and yeasts occurred most frequently immediately after glyphosate treatment but as retting progressed the frequency of occurrence of Fusarium culmorum, Alternaria alternata and a Phoma sp. increased. Many of the fungi isolated from retting flax were also present as epiphytes on healthy flax stems. Glyphosate was shown to be fungitoxic in vitro but it had only a very slight effect on fungi colonising the flax. The application of sucrose and urea to flax 1 wk after glyphosate treatment resulted in more rapid fungal colonisation of the stems, but did not significantly enhance retting. When grown on sterilised flax stem sections, fungi known to be saprophytic on flax produced polysaccharide-degrading enzymes. All seven fungi tested produced polygalacturonase, pectin-lyase and xylanase. The greatest cellulase activity was present in stem tissues inoculated with F. culmorum and the Phoma sp. while no cellulase was detected in tissue inoculated with B. cinerea, a Mucor sp. or a Penicillium sp. Extracts from flax inoculated with the cellulolytic fungi caused the solubilisation of native cellulose. Pectinases, xylanase and cellulase were also detected in naturally-colonised senescing and dead flax stems. Stems which had been treated with a sucrose solution tended to contain the greatest enzyme activity.     

Flax cultivation and textile production in Neolithic wetland settlements on Lake Constance and in Upper Swabia (south-west Germany)

At present there are substantial amounts of archaeological and archaeobotanical data from the Late Neolithic wetland settlements of southern Germany on the oil and fibre plant flax (Linum usitatissimum L.). This is the result of 30 years of intensive excavations and research in 53 settlement areas. This article, on the one hand, will present the significance of flax remains, products made of flax and the inventory of relevant tools for evidence of and reconstruction of the flax production processes. On the other hand, based on the quantitative analysis of flax remains, the changing significance of this important cultivated plant during the course of the Late Neolithic will be demonstrated. From this it will be evident that textile production and in particular flax processing were part of a decisive upheaval in cultural development that initiated the transition to the middle phase of the Late Neolithic in the fields of agriculture and technology.     

First and second millennium a.d. agriculture in Rwanda: archaeobotanical finds and radiocarbon dates from seven sites

This article presents the results from a programme of bulk soil sampling and flotation of first and second millennium a.d. early farming, ‘Iron Age’, archaeological sites in Rwanda conducted in 2006–2007 alongside a new set of associated radiocarbon dates, which contribute toward the development of a chronology of plant use for the region. This research has identified the earliest examples of pearl millet (Pennisetum glaucum), finger millet (Eleusine coracana) and sorghum (Sorghum bicolor) in Great Lakes Africa and thus this article also discusses the significance of these finds within the later archaeology of the region and presents a brief synthesis of the direct archaeological evidence for finger millet in sub-Saharan Africa.     

Flax for oil or fibre? Morphometric analysis of flax seeds and new aspects of flax cultivation in Late Neolithic wetland settlements in southwest Germany

The transition from the early to the middle phase of the Late Neolithic (fourth–third millennium b.c.) is closely connected with the term “secondary products revolution”, which involves the adoption of animal traction and an increased production of rendered animal commodities such as wool and dairy products. Based on measurements of Linum usitatissimum L. (flax) seeds and their abundance in 32 wetland settlements in southwest Germany, we presume that the introduction of a new flax variety, maybe a better flax for fibre, and the intensification of flax cultivation were also a part of this process. The morphometric analysis shows that flax seed sizes in the early phase of the Late Neolithic (4000–3400 cal. b.c.) differ significantly from those of the middle and latest phase (3400–2400 cal. b.c.).     

Engineering of PHB synthesis causes improved elastic properties of flax fibers

Flax stem is a source of fiber used by the textile industry. Flax fibers are separated from other parts of stems in the process called retting and are probably the first plant fibers used by man for textile purposes (1). Nowadays flax cultivation is often limited because of its lower elastic property compared to cotton fibers. Thus the goal of this study was to increase the flax fiber quality using a transgenic approach. Expression of three bacterial genes coding for beta-ketothiolase (phb A), acetoacetyl-CoA reductase (phb B), and PHB synthase (phb C) resulted in poly-beta-hydroxybutyrate (PHB) accumulation in the plant stem. PHB is known as a biodegradable thermoplastic displaying chemical and physical properties similar to those of conventional plastics (i.e., polypropylene). The fibers isolated from transgenic flax plants cultivated in the field and synthesizing PHB were then studied for biomechanical properties. All measured parameters, strength, Young's modulus, and energy for failure of flax fibers, were significantly increased. Thus the substantial improvement in elastic properties of fibers from the transgenic line has been achieved. Since the acetyl CoA, substrate for PHB synthesis, is involved not only for energy production but also for synthesis of many cellular constituents, the goal of this study was also the analysis of those metabolites, which interfere with plant physiology and thus fiber quality. The analyzed plants showed that reduction in lignin, pectin, and hemicellulose levels resulted in increased retting efficiency. A significant increase in phenolic acids was also detected, and this was the reason for improved plant resistance to pathogen infection. However, a slight decrease in crop production was detected.     

A new find of macrofossils of feather grass (Stipa) in an Early Bronze Age storage pit at Vliněves, Czech Republic: local implications and possible interpretation in a Central European context

The abundance of Stipa remains in material dated to the Middle Neolithic (ca. 4400–4000 b.c.) from Kujawy (central Poland) and their presence in a storage pit at Vliněves (Czech Republic) dated to the Early Bronze Age (ca. 2300–1600 b.c.) are most probably connected with gathering of the plant. Stipa grains are edible and the whole plant could have been used as insulation, for making mattresses and for a range of similar purposes. Nowadays spikelets of Stipa are used for decoration. They are dangerous to herbivores because of the sharpness of the basal part of the spikelet and the tendency of the awns to unroll in wet conditions. Already in the first half of the 20th century the plant was regarded as a weed of meadows. The gathering and use of Stipa, as suggested by the abundance of its archaeological macro-remains, was most probably prompted by changes in the local environment. These latter arose from intensive human activity, mostly deforestation and grazing by domestic animals, leading to the formation of steppe-like vegetation. This process is documented by a pollen diagram from a peat section located near the Vliněves site.     

The retting of flax after preservation with sulphur dioxide

Experiments were carried out to compare the retting of moist flax preserved with sulphur dioxide with that of green dried flax, using whole straw samples. When retted in water at either a constant 20°C or 28°C dried flax was fully retted after 15 and 10 days respectively whereas the sulphur dioxide treated flax (20 g sulphur dioxide kg“¹ flax DM) had undergone almost no retting after 20 days at 20dC or 10 days at 28°C. Pre-soaking the treated flax for 24 h in water and changing the acidified water, raised the pH of the retting liquor to a more normal value but did not significantly increase the rate of retting. Addition of the pectinase enzyme preparation ‘Flaxzyme’ to retting liquor at the rate of either 1.5 g kg^-1 or 3.0 g kg^-1 water, and at a constant temperature of 20°C, substantially increased the rate of retting of both sulphur dioxide treated and dried flax. Optimum degree of retting was achieved at 24 h with the treated flax and at 97 h with the dried flax. Pre-rinsing of the sulphur dioxide treated straw only served to reduce the rate of retting. It was concluded that natural water retting of sulphur dioxide treated flax is retarded by the presence of acidic residues of sulphur dioxide, while enzyme retting is enhanced by these. In further smaller scale experiments using bundles of cut flax straw Flaxzyme was added at concentrations ranging from 0–8.0 ml litre ¹ to containers containing flax in water at ratios from 1:10 to 1: 600 flax:water and the producion of galacturonic acid was used as an indicator of retting progress. Retting took place more rapidly at higher flax to water ratios for a given enzyme concentration. This effect was attributed to the lower pH of higher flax to water ratios which created pH conditions closer to the pH optimum for the retting enzymes. When enzyme retting was compared at a range of buffered pH's the optimum was pH 4.0. At a buffered pH of 4.0 and a temperature of 19°C, retting of sulphur dioxide treated moist flax (flax to water ratio of 1:10) was achieved with Flaxzyme concentrations as low as 0.5 ml litre”‘,much lower than the previously reported minimum of 3.0 ml litre’.     

In vitro evaluation of dew-retting of flax by fungi from southern Europe

Flax dew-retting is widely adopted in most flax-growing countries, but it does not represent a practical solution where dry weather conditions occur after harvest. A study of the local microbiological aspects was undertaken as a contribution to improve field-retting of flax under southern European climates. Fungi were isolated from soil and dew-retted flax in northern Italy, and 23 representative strains were chosen to test their ability to ret flax stems. Experiments were performed in vitro on flax stem pieces artificially inoculated with single fungal strains. Retting degree was assessed with a mechanical test, to evaluate the ease with which the bast was detached from the wood core, and by the analysis of the residual fibre pectins using uronic acid. Uronic acid dosage provided a better differentiation of the strains than the mechanical test. There was a large variability in retting ability among the species assayed and even among strains of the same species. The best results were obtained with all Aspergillus and Penicillium strains, while Mucor and Rhizopus strains showed a variable retting ability. Fusarium, Trichoderma strains and Epicoccum nigrum had the poorest retting abilities among all the fungal strains assayed.     

New archaeobotanical finds of Isatis tinctoria L. (woad) from Iron Age Gaul and a discussion of the importance of woad in ancient time

Although chemical analyses of textile remains have traced the use of Isatis tinctoria L. (woad) back to the Neolithic period, archaeobotanical remains of the plant are scarce in north-western Europe, especially in France. A new discovery in the rural settlement of Roissy, north of Paris, raises the question of local cultivation of woad from at least the fifth–fourth century b.c. (La Tène A/B1) in northern Gaul. The plant assemblage comes from the filling of a storage pit, which also included a wide variety of cultivated plants. These data represent a valuable contribution to the study of the circumstances of the adoption of woad as a new crop.     

Prehistory of plant growing and collecting in northern Italy, based on seed remains from the early Neolithic to the Chalcolithic (c. 5600–2100 cal b.c.)

The stages of the early Neolithic and the spread of agriculture in northern Italy are difficult to determine and basically still unclear, since this region was influenced by deeply different cultures coming from both the Mediterranean coasts and the Balkans. The complex interrelations due to the contributions from both cultures are reinterpreted here thanks to recent data, modifying a picture which 15 years ago was believed to be definite. According to radiocarbon chronology, the appearance of the earliest farming communities in northern Italy should be dated around 5600–5500 cal b.c. Early farmers cultivated several cereal and pulse taxa, of which the more important were Hordeum vulgare/distichum, Triticum dicoccum, T. monococcum, T. aestivum/durum/turgidum, Lens culinaris and Pisum sp. In addition they gathered many wild plants. The spread of agriculture was a rapid phenomenon and within a few centuries agriculture was established into the Alps. Little is known about the middle and late Neolithic, with the Square-mouthed pottery culture “Bocca Quadrata”, from c. 5100 cal b.c. onwards, since most of the archaeological features discovered up to the present have produced only a few plant remains. We demonstrate the introduction of poppy and a few other innovations like a slightly increased cultivation of free-threshing cereals and flax. Archaeobotanical analyses from Chalcolithic or Copper Age settlements, from c. 3500 cal b.c. onwards, are even scarcer and a comparison with the earlier Neolithic settlements does not yet seem possible.     

Flax processing in the Neolithic and Bronze Age pile-dwelling settlements of eastern Switzerland

Numerous artefacts from the area of textile production as well as finished products, fabrics and netting, dating from the period between 3900 and 800 b.c. have survived in the archaeological layers of late Neolithic and Bronze Age wetland settlements in eastern Switzerland. Archaeological investigations, experiments in textile technology and comparisons with Egyptian wall paintings, as well as analyses under the scanning electron microscope, allow us to almost completely reconstruct Neolithic textile production in prehistoric pile dwellings.     

The role of bacteria in retting of desiccated flax during damp weather

Summary The bacteria present on samples of desiccated flax stems were Bacillus mycoides, B. subtilis, Erwinia carotovora, Pseudomonas fluorescens, P. putida and Micrococcus sp. and the fungi present were Cladosporium herbarum, Fusarium culmorum, Botrytis cineria, Epicoccum nigrum and yeast. When inoculated on autoclaved stems or in liquid culture, B. subtilis produced mainly pectin-lyase and xylanase. However, only pectin-lyase was detected in significant levels in autoclaved stem sections or in liquid cultures inoculated with E. carotovora. Enhanced pectin-lyase and xylanase levels were detected in field-retted stems sprayed with B. subtilis compared with enzyme levels in stems sprayed with E. carotovora or the control stem tissues. Increases in the fungal population coincided with a reduction in the bacterial population on treated stems at the later part of retting. Enhanced retting was observed in stems sprayed with B. subtilis and consequently the stems produced finer fibres than fibres from E. carotovora-sprayed or control stems.     

Changes in cereal cultivation during the Iron Age in southern Sweden: a compilation and interpretation of the archaeobotanical material

Macrofossil data from 73 sites dating to the south Swedish Iron Age (500 b.c.–a.d. 1100) have been compiled and analyzed in order to elucidate long term changes in cereal cultivation. The analyses indicate that “permanent field” agriculture was established at the end of the Bronze Age utilizing Hordeum vulgare var vulgare as a primary crop and Triticum aestivum ssp vulgare/compactum, Triticum spelta/dicoccum/monococcum, Avena sativa and Secale cereale as secondary crops. An observed change towards the end of Roman Iron Age (1–a.d. 400) is the expansion of Secale cereale and Avena sativa cultivation. Evidence also suggests that winter sowing of the former commenced at the latest during the eighth, ninth and tenth centuries a.d. The introduction of winter sowing possibly coincided with the establishment of crop rotation agriculture. During most of the Iron Age southern Sweden displays significant regional variations with regards to cereal cultivation practice. There is however evidence that a more homogenous agriculture appeared across the investigated area from the beginning of the Viking Age (a.d. 800–1100) onwards.     

Archaeological evidence of former occurrence and changes in fishes, amphibians, birds, mammals and molluscs in the Wadden Sea area

Animal remains are well preserved in archaeological sites, especially the terp sites, of the Wadden Sea area of Denmark, Germany and The Netherlands. Here, we provide an overview on the wild mammals, birds, fishes, amphibians and molluscs found in coastal sites dating from 2700 to 2600 B.C. and 700 B.C. to A.D. 1600. Coastal people used a variety of animal species for food and other purposes. Hunting, fowling, fishing and agriculture did not have much influence on wild stocks in the period from the late Bronze Age/early Iron Age until the late Middle Ages. However, large changes to the landscape were made in the late Middle Ages by diking and damming. As a result, some species such as the northern vole (Microtus oeconomus) and the natterjack toad (Bufo calamita) disappeared from the area except for some dune districts on the islands, and others became rare, such as the grey seal (Halichoerus grypus) and the lagoon cockle (Cerastoderma lamarcki). New habitats arose for birds of dry meadows and fields, like lapwing (Vanellus vanellus) and black-tailed godwit (Limosa limosa). Sturgeon (Acipenser sturio) disappeared from the Wadden Sea within a few decades since A.D. 1890 due to the destruction of spawning grounds by damming and high exploitation pressure. Our findings are important for the ecological history of the region.     

Carthamus species in the ancient Near East and south-eastern Europe: archaeobotanical evidence for their distribution and use as a source of oil

We present an overview of archaeobotanical Carthamus spp. finds from Neolithic to medieval sites in the Near East and adjacent areas. A particular focus is put on the cultivated form of the genus. Safflower appears first in a number of early Bronze Age (3000 b.c.) sites in northern and central Syria. From there it apparently spread to Egypt, the Aegean and south-eastern Europe. The Near Eastern Bronze Age evidence shows a striking exclusiveness in the distribution patterns of safflower and flax, with flax being restricted to Levantine and Iranian sites. This may reflect the contrasting ecological requirements of the two crops, with safflower being well adapted to drought and salinity and thus to arid conditions. At the same time the geographically complementary evidence may indicate a similar use of the two crops and most probably suggests that the safflower was also used for oil almost from the beginning of its cultivation. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

T’ef (<Emphasis Type="Italic">Eragrostis tef</Emphasis>) in Ancient Agricultural Systems of Highland Ethiopia

T’ef ( Eragrostis tef ) in Ancient Agricultural Systems of Highland Ethiopia. T’ef (Eragrostis tef) has been cultivated in the Horn of Africa for at least 2,000 years. The earliest known agricultural systems in this region date to the Pre-Aksumite period (800–400 b.c.) and appear to have focused on Near Eastern crops, with indigenous African species increasing in importance during Aksumite times (400 b.c.–a.d. 700). While palaeoethnobotanical data are available from Pre-Aksumite and late Aksumite periods, macroscopic botanical remains from the site of Ona Nagast, northern Ethiopia, provide a first glimpse of agricultural systems dating to Proto-Aksumite (400–50 b.c.), Early to Classic (50 b.c.–a.d. 340), and Post-Aksumite (a.d. 700–900) times. Archaeological t’ef remains from Ona Nagast are examined in detail. Guidelines are developed for the identification of t’ef grains preserved on archaeological sites, with a focus on how to differentiate them from seeds of wild Eragrostis species. Charring experiments reveal that in some cases t’ef may not survive high temperatures tolerated by larger cereal grains, such as wheat and barley. The domestication history of t’ef appears to be different from some other cereals, a factor which may explain the preponderance of indeterminate Eragrostis seeds in archaeological samples. Selection of large seed size and intensified tillage were not key factors in t’ef domestication. Early cultivators were likely selecting for increased branching and higher percentage seed set under conditions of minimal tillage.