ÇATALHÖYÜK 2003 ARCHIVE REPORT

Summary of plant processing experiments at Çatalhöyük, August 1999

Michèle Wollstonecroft and Aylan Erkal **

Introduction

Charred seeds and tubers of sea club-rush are well represented within the Neolithic and Chalcolithic contexts of Çatalhöyük (Çatalhöyük 1999 Archive Report; Hather, cited by Hastorf pers. comm.). Sea club-rush (known as Scirpus maritimus or Bolboschoenus maritimus subsp. tuberosus and subsp. maritimus (Desf.) (T. Koyama 1980), is a semi-aquatic perennial sedge which is found in saline and fresh-water wetland environments (Tackholm and Drar 1950). (Plate 1). Varieties of this species are found throughout the northern hemisphere (Kantrud 1996). At the time that Çatalhöyük was occupied, large stands of sea club-rush were probably abundant in the surrounding wetland (N. Roberts pers. comm.). Sizeable stands continued to grow in the area up to the 1970’s (Erkal 1999; G. Hillman pers. comm.).

Our research is concerned with the potential uses of sea club-rush as a food. This plant has edible seeds, tubers and shoots and commonly grows in large stands, making it a readily accessible and possibly nutrient-rich resource (Kantrud 1996). The raw seeds (nutlets) (Table 1) and tubers (Table 2) appear to be comparable in energy, protein and carbohydrates to other plants which have been used as staple foods by human groups in different parts of the world.

Table 1 Average nutrient composition of several starch-rich wild and domesticated seed foods

Table 2 Average nutrient composition of several wild and domesticated root foods

The presence of significant amounts of both wild and domesticated plant remains at Çatalhöyük implies that the economic and social practices were multifarious in character. The diversity of resources used by this Neolithic community gives rise to questions about the division of labour, task group composition, task group activities and habitual movements over the landscape, specialised activities, agricultural practises and the possible management of wild resources and, how all these elements of daily life and annual cycles fit within the economic, symbolic and cultural meanings and values of the society. The recovery of comparatively large quantities sea club-rush tubers at Çatalhöyük raises further questions about how and why this starch-rich wild plant was used, given that this agricultural community presumably obtained most of its carbohydrates from their domesticated cereals and pulses.

The purpose of our study of S. maritimus is to better understand the potential uses of this plant in order to suggest its role(s) within the customs of Çatalhöyük. Understanding how sea club-rush was used at Çatalhöyük may also provide valuable insights into its uses at other sites in Southwest Asia. Human uses of this plant appear to have a long time-depth and to have covered a wide geographic area. The earliest evidence of human use of sea club-rush is 18,000 BP and includes both tubers and nutlets recovered from the Late Pleistocene hunter-gatherer site of Wadi Kubbaniya in northern Egypt. We know that S. maritimus was used as food at this site because both the nutlets and the tubers were identified within the charred remains of human faeces (Hillman, Madeyska and Hather 1989). The nutlets of sea club-rush have also been recovered from earlier sites in Southwest Asia including the Epipalaeolithic and Neolithic sites of Hallan Çemi Tepesi and Çayönü in Anatolia; Abu Hureyra in Syria; several early sites in the Azraq basin of East Jordan; and in the Levantine corridor (Colledge n.d.; Hillman n.d.; Hillman, Colledge and Harris 1990; Rosenberg 1994; van Zeist and de Roller 1991-1992). The fact that this sedge occurs at so many early sites in this region suggests that it was of great importance in the economies of Near Eastern Peoples during pre-agrarian and early agrarian times.

Ethnographic and ethnohistoric reports indicate that throughout Asia and Europe sea club-rush tubers were mainly eaten during periods of food scarcity, typically being processed into a flour (Arora and Pandey 1996; Bryant 1783; Hedrick 1919). Bryant (1783) reports the use of sea club-rush tuber flour as a starvation food in England as late as the 18^th century. In India this flour appears to have been used until the twentieth century, again during times of food shortages (Arora and Pandey 1996; Hedrick 1919). Similar tuber-bearing sedges are widely reported as having food uses by aboriginal peoples in Australia and North and South America (Cane 1989; Ebeling 1986; Hastorf pers. comm.; Ungent pers. comm.).

Although there are many reported cases of sea club-rush tubers having been used as a food source, many questions about its usage remain. For instance, the ethnographies give little explanation as to how these tubers and nutlets were prepared and consumed. Also unknown are the effects of different preparation methods on the overall quality of the food including changes to the edible nature of the tuber, the nutrient content, its taste and its preservation potential (see Stahl 1989). (Plate 2) Finally its is unclear from the literature when or why people stopped eating these tubers.

It is with an eye to resolving some of these questions that during August of the 1999 field season we carried out both ethnographic and experimental research at Çatalhöyük (see Erkal 1999). Our main aims were twofold: to conduct controlled harvesting experiments in order to observe how much time was required to collect sufficient amounts of tubers; and to process the wild tubers into an edible form. Given the ethnographic evidence that sea club-rush tubers can be made into flour that can be baked into a bread (Arora and Pandey 1996) we focused on producing a flour and baking it into bread using traditional local methods. During the 1996 season we experimented exclusively with the tubers however we intend to carry out similar experiments with the nutlets in future.

In this project we consulted with and enlisted the help of Bayan Medine Tokyağsun of the nearby village of Küçükköy because of her expertise in traditional bread making. Bayan Tokyağsun, now a grandmother, is an expert bread-maker who has for many years produced loaves of wheat bread to feed herself and her extended family. Of particular significance is the fact that Bayan Tokyağsun bakes bread in a tandır. (Plate 3) A tandır is a circular bread-oven, typically made from mud-brick which is heated by burning cattle dung in the centre of the oven base. The bread is baked against the hot inside walls of the tandır, the unbaked loaves being pressed onto the walls where they adhere and bake. This type of bread-oven is typical throughout Western Asia and there is also evidence for similar ovens at Çatalhöyük (Çatalhöyük 1999 Archive Report).

Research Methods

Harvesting

Because of the current desiccation of the Konya plain, wetlands are becoming scarce in this area. During the 1998 and 1999 seasons we surveyed the region for wetlands which support sea club-rush with little success. Our specimens were thus collected from homogenous stands of sea club-rush that grow in an irrigation canal near the Çatalhöyük site. (Plate 4) Also growing in the canal are two other edible species that are frequently found in early sites in the region: Typha domingensis also a semi-aquatic, forms homogenous stands that are interspersed between those of sea club-rush and Rumex grows on the dry banks of the canal. The water levels ranged from 20 cm on the edge to about 80 cm in the centre of the channel.

Harvesting experiments were made to establish the types of tuber yields that are possible from stands of S. maritimus var. tuberosus in this region and to compare our yields (grams collected per hour) with that of harvesting experiments carried out in East Sussex (Britain) on S. maritimus var. maritimus. We recorded the procurement times, the area covered during those procurement times, the quantity of tubers collected (number and weight) and the characteristics of the tubers (immature, mature, and past maturity). We also aimed to determine the best way to loosen the tubers from the dense rhizomatous muddy substrate including hand-pulling, as well as using a "digging stick", a shovel and a rake.

Six harvesting experiments were carried out by three admittedly inexperienced harvesters (the authors with the generous assistance of Başak Boz). We found that, unlike the bulbs, tubers and taproots of geophytes such as those of the Asteraceae, Iridaceae and Liliaceae which are best uprooted using a digging stick (see Ertug-Yaraş n.d. and Thoms n.d.), sea club-rush tubers are best uprooted from their aquatic substrate by hand-pulling. (Plate 5) Using this method we collected, on average, 475 g tubers fresh weight per hour covering approximately 1.5 - 2 square m. of area.

Processing

Excluding the harvesting and transporting of the sea club-rush tubers to the site, we generally followed five stages in processing: washing, soaking, peeling, pounding (into flour) and finally, baking the flour into a bread. The tubers are most easily and quickly cleaned by washing them in the canal when they are uprooted. Upon our return to the dig-house we also hosed off the tubers in order to insure that all the grime from the canal was removed.

The next task was finding the best method to peel away the two outer layers (periderm and cortex) from the tubers in order to get at the edible starch. We tried soaking, boiling and charring in a fire as well as air-drying the tubers in hopes of detaching these tough layers but, regardless of their freshness and the method used, peeling was found to be immensely time-consuming. Working with Bayan Tokyağsun and her daughter-in-law, Fatima, we used small sheers and knives to peel the tubers. (Plate 6) It took several hours to peel 144 g (fresh weight) of tubers. (Plate 7)

Once we had peeled the tubers, we set about pounding them into flour. In the course of this work we observed that the mature tubers are extremely hard and cannot be eaten without some form of processing. On the other hand, the immature tubers can be eaten raw as they have not yet developed the tough periderm and cortex and, the starchy layers are still fairly soft. (Plate 8) In fact, they have a crisp and starchy consistency similar to that of the water chestnut (Eleocharis dulcis).

In order to pound the mature and immature tubers into flour we used two second-hand wooden mortars that were purchased in the nearby town of Konya for this purpose. These mortars differ in shape and we utilised them in different ways. The first has a curved, shallow basin and is paired with a short-handled, curved mallet and we used it while in a sitting position. The other mortar is taller and deeper than the first and has a more rectangular-shaped basin and is used with a pestle-type pounder. We were able to use this mortar in both a sitting and a standing position by alternating between longer and shorter pounders. (Plate 9) Bayan Tokyağsun said that mortars similar to these were used in the Konya Basin in the recent past for pounding bread wheat by those who were unable to pay for mechanised milling.

Regardless of which tools were used, the pounding work was time consuming. Soaking the tubers prior to pounding significantly reduced the processing time but it still took one hour of work to produce 25 g flour. (Plate 10). Further trials with a stone mortar and pestle produced the same results.

Bayan Tokyağsun began preparing the dough by combining 200 g of sea club-rush flour and one cup of water and then kneading the mixture. (Plate 11) She tested the dough by making small patties and found that the consistency was not suitable as a bread dough. (Plate 12). Consequently she added about ¼ cup bread wheat flour and an additional 2 cups of water to the sea club-rush flour. Eight small loaves were produced, each measuring about 10 x 12 x 1.5 cm. (Plate 13)

The loaves were placed into the tandır for 20 minutes. (Plate 14) Like other tandır-baked breads, the sea club-rush loaves were placed on and adhered to the inside walls of the oven during baking. Using a thermocouple device, we measured the temperature of the oven and found that the fire itself reached a temperature of 620ºC and the walls reached 433ºC.

The resulting "bread" had an overall sweet taste. It had a well-cooked outer crust but was rather soft and gritty in texture on the inside. (Plate 15) Three of the loaves were kept aside for further study while five were broken into pieces and tasted by members of the Çatalhüyük team. Responses to the taste ranged from those who said that they did not like it to those who said that they felt it had potential, resembling bran muffins or a Germanic or Scandinavian bread.

Discussion

There are of course many other ways that prehistoric people may have used sea club-rush that are not addressed in this study. The plants may have been used as a flavouring, as a beverage, for medicinal purposes or even as a dye. It is also possible that the tubers and nutlets were brought onto early sites unintentionally if the plant was harvested as forage for domesticated animals or contained within animal dung which was burned as fuel. The leaves and stems may also have been used to fabricate parts of the shelter, matting or clothing. As reported by Erkal (1999), in the Konya basin today village women flatten and weave the stems of sea club-rush into matting that is placed between the wool carpets and the floors in houses. A similar sea club-rush matting is also used to cover the ceiling in some rooms. Further, sea club-rush tubers are found today within the mud brick garden walls of the houses in the village of Küçükköy. Villagers explained that the roots and tubers of sea club-rush are often intentionally dug up with the mud used to make mud-brick, as they are said to add strength to the structure. Interestingly, the villagers also explained that when such walls begin to decay and the tubers fall out, they are often thrown into the hearth.

Consequently, we cannot assume that the recovery of these charred tubers at archaeological sites is evidence of their consumption as food. In order to address this concern we collected and set aside samples of the tubers and the debris from all stages of our processing. Although it was not feasible to analyse these materials during the 1999 field season, we plan to examine them in future for the purpose of determining if they exhibit any characteristics that are indicative of the processing methods that we used to produce them (see Hillman 1981).

From the harvesting experiments is our impression that, given the amount of effort required to uproot the tubers from their muddy substrate, they would not have been brought to the site accidentally. Certainly, if the sea club-rush was collected exclusively for its stems/and or nutlets, it would have been easier to cut the stems or hand pull the nutlets, rather than uprooting the entire plant from below the water. Furthermore we observed that sea club-rush grew in areas that have been grazed by animals, and although the plant had been eaten down to near the base of the stem, the lower stems, roots and tubers remained intact. This suggests that it is also unlikely that the tubers were introduced to archaeological sites as forage or within animal dung.

The harvesting return of 475 g. per hour from the irrigation canal near Çatalhöyük is significantly lower than the yield obtained in identical trials by M. Wollstonecroft in East Sussex, (southern Britain) with S. maritimus var. maritimus. There yields of up to four times this amount were obtained. Many factors may account for this variation, including possible biological differences between the English samples (var. maritimus) and the Turkish samples (var. tuberosus). Unfortunately little research exists on the similarities and differences between these two varieties. It is also possible that the difference in yields between these two varieties is the result of ecological and biological differences between their respective wetland habitats. To complicate matters further, there are a large number of factors that affect the growth and reproduction of stands of Scirpus from year to year including fluctuations in water levels and salinity. In their study of S. maritimus var. paludosus Lieffers and Shay (1981, 1982) found a direct correlation between underground biomass and water depth. Optimum tuber growth is achieved in water levels between 25 and 35 cm as when water levels increase beyond this depth sea club-rush shifts from vegetative to seed reproduction strategies. Consequently, the number and size of the tubers that a plant produces may vary from year to year.

The uprooting of the tubers requires a concerted effort but no special tools nor particular skills. Therefore, in trying to identify task group composition and ascertain those who would have carried out this work at Neolithic Çatalhöyük, it is important to remember that this job could feasibly have been carried out by any members of the community including children and elderly people.

Our processing experiments demonstrate that sea club-rush can indeed be made into a palatable food. (Plate 16) We are seeking more expedient methods of peeling and pounding the tubers and recognise that these tasks most likely involve skills that neither of the authors currently possesses. However, it is possible that long processing times which we experienced may not have been perceived as a problem for the individuals responsible for this task at Çatalhöyük. To draw on an ethnographic example, Williams (1979:342-344) reports that in traditional methods of processing cassava (Manihot esculenta) tubers in Nigeria, it took a small group of women (the number is not specified) approximately 93 hours to process 103 kilograms of the tuber. Williams observed that 65% of the total hours required for processing the tubers was spent in peeling them. Interestingly, the cassava owner treated the activity as social occasion, enlisting the co-operation of other women relatives and friends. Williams further comments that the women did not appear to rush to finish this task but instead seemed to view the work as an opportunity to visit and socialise.

Our processing experiments have established that the fine flour which was produced from the sea club-rush tubers is suitable for bread making using traditional Southwest Asian methods. On its own this flour did not make a workable dough so we need to consider what types of other ingredients might be added. Interestingly, studies in producing breads made from "composite flours", combining wheat and non-wheat ingredients, demonstrate that optimum results are achieved when no more than 20% non-wheat flours, such as root crop flours, are added (Coursey and Ferber 1979; Rasper et al. 1974). However, according to Rasper et al. (1974) and Okaka and Potter (1977) the addition of non-wheat flour, such as yam (Dioscorea spp.) or legume flour, to wheat bread may impart an improved flavour and increase the breads’ nutrient content as well as strengthening its physical properties. According to Bayan Tokyağsun, a number of different types of flour, such as walnut, have been used in recent times by villagers in the Konya basin. Consequently we argue that it is possible that the residents of Çatalhöyük also produced flour from a number of different non-wheat wild (e.g. sedges) and domesticated (e.g. pulses) resources.

As a result of our experiments and discussions with Julie Near about the archaeobotanical assemblage at Çatalhöyük, we have concluded that the carbohydrate-rich sea club-rush tubers could potentially have been used by this community to compliment and/or extend their cereal supply. It is possible that this tuber provided a critical source of carbohydrate when the winter stores of wheat began to diminish and/or in times of crop failure. The tuber flour may have been mixed with other ingredients such as other flours to produce, bread, gruel and/or a type of dumpling or thickening agent for mixing into soups.

We suspect that the uneven, "gritty" texture of our sea club-rush bread was due to the fact that some of the starch did not gelatinise during cooking. This may be due to the fact that some of the tubers were not soaked before they were pounded into flour. Alternatively, the gritty texture may be due to the fact that dough made from the flour of this particular tuber may require a different cooking regime than the wheat dough normally cooked in the tandır. It has been observed that bread made from rye flour requires longer cooking at lower temperatures than loaves made from wheat flour (Davıdek et al. 1990). Thus we need to try other ways of baking, experimenting with times and temperatures.

It is possible that sea club-rush, a self-storing resource, was harvested from the marsh year-round, which suggests that the surrounding wetlands provided an unlimited carbohydrate supply for Çatalhöyük, precluding the need for preservation and storage of this plant. On the other hand, we need to consider the possibility that the tubers are more edible within certain seasons, or preferred when collected at a specific time. In order to determine if the sea club-rush tuber is in fact palatable, nutritious and accessible throughout the year, future harvesting experiments will entail collecting sea club-rush in different seasons and identifying any seasonal variations in the nutrient content. Future processing experiments will entail searching for ways that the tubers might be prepared as a vegetable (such as by steaming, boiling, frying, etc.) and determining their preservation and storage potentials. These trials will be accompanied by M. Wollstonecroft's laboratory study of the nutrient composition of the raw tubers and observations about the effects of processing on the nutrient composition of the tubers.

Conclusion

From the archaeological and ethnographic records it is clear that sea club-rush has been used by groups throughout Southwest Asia for the last 18,000 years. All parts of this plant have reported economic uses: the starch-rich nutlets and tubers provide food resources and the tubers and stems provide raw materials used to fabricate domestic structures and also to weave wall and floor coverings. From our experiments thus far, we have determined that the tubers of sea club-rush are edible both as a raw vegetable (the immature tubers) and as flour (both the immature and mature tubers) from which other foods can be prepared. Our experiments also demonstrate that a composite sedge/wheat flour can be baked into bread using traditional technology that is presently known across Southwest Asia, technology that is possibly similar to that known at Çatalhöyük during the Neolithic. We argue that the residents of Çatalhöyük may have utilised the surrounding wetlands as a larder from which critical resources, such as the tuber of sea club-rush, were available year-round. The greatest deterrent to using these tubers as food seems at this point to be the long processing time. Future experiments are aimed at finding more expedient ways to clean, peel and pound these tubers.

**Note:

These experiments are part of a series of experiments by Michèle Wollstonecroft for her PhD research at the Institute of Archaeology, University College London. This dissertation concerns the possible role of plant-food processing methods in the resource intensification and socio-economic shifts that took place in Southwest Asia during the Late Pleistocene and early Holocene. This multidisciplinary project draws on recent research in food and nutrition sciences, ecology, biology as well as ethnography and archaeology. The experiments at Çatalhöyük are also part of Aylan Erkal’s ethnobotanical study of plant-use in several different environmental zones within the Konya Basin which constitutes her MSc. research at the Middle East Technical University, Ankara.

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