Zhao Zhijun Eastward Spread of Wheat into China – New Data and New Issues Zhao Zhijun* Key words: Wheat–Diffusion Agriculture–History Eurasia Steppe Flotation Northern Frontier Zone From the beginning of the 21st century, flotation tech- Introduction nique has been widely applied by Chinese archaeology It is well known that wheat was originated in the West as means of obtaining ancient plant remains during rou- Asia. It was introduced into China, and eventually be- tine archaeological excavations. Up to the present, flo- came the dominant crop in the dry-land agriculture of tation work has been practiced at more than one hun- Northern China after replacing the major native crops dred archaeological sites of diverse time periods, and of foxtail millet and broomcorn millet. Yet, neither the large amounts of plant remains of high research poten- time when it arrived in China nor the routes through tial have been found, including wheat remains. These which it was introduced are made clear. Therefore, these new discoveries provide significant archaeological evi- are the major problems we are now dealing with. dence for a better understanding of the spread of wheat It has been widely agreed that the introduction of into China, the route and the temporal-spatial background wheat into China should have occurred before the his- in which the introduction events took place. The present torical time, because the script “来”for “wheat”has paper is aimed at synthesizing these new data, referring been identified from records on oracle bones of the Shang to those data of early wheat remains reported in last Dynasty. Some scholars even believed that the script of century, to explore these issues. “来”may be a metaphor of the introduction of wheat Note that the term of “early wheat remains”used from outside China, simply because this script means in this paper specifically indicate the data which were “coming” in both classic and modern Chinese language dated 3000 BP or earlier. (He 1985), while, other scholars do not consent to this Previous Wheat Remains viewpoint (Luo 1990). Although wheat is commonly documented in pre-Qin literatures, the time and routes Before flotation technique is used in Chinese of its introduction are not mentioned at all. Therefore, archaeology, wheat remains were occasionally reported the spread of wheat into China has become a rigorous to be found at some archaeological sites, such as Donghui inquiry for archaeological study. Mound in Minle County, Gansu (Li Fan et al. 1989), Hard evidence for confirming the spread of wheat into Zhaojialai in Wugong County, Shaanxi (Zhongguo China should be surely those wheat remains from an- 1988), Diaoyutai in Boxian County, Anhui (Yang 1963), cient times. However, wheat remains are readily to de- and Shirenzi in Barkol, Wupu Tombs in Hami and the cay and not likely to be well preserved in archaeologi- burial site of Lop Nor, Xinjiang (Wang 1983). It must cal assemblages because of its organic composition. be pointed out that the wheat remains referred to in these Also, crop grains as small as wheat seeds are not easily archaeological reports were actually discovered by to be identified by the naked eye during excavation. This chance, and their taxonomic identification and dates may causes the difficulty for plant evidence collection. not be firmly assured and hence remained some contro- * The Institute of Archaeology, Chinese Academy of Social Sciences, Beijing, 100710 Email: [email protected] Volume 9 1 Eastward Spread of Wheat into China – New Data and New Issues versial issues. Fourteen barley and wheat specimens were chosen for For instance, the wheat remains of the Diaoyutai site AMS radiocarbon dating test. These plant remains were had been found inside a pottery li-鬲 tripod, which was all dated to a period between 3700 and 3300 BP, which firstly classified as a Neolithic pottery, while reclassi- exactly is the Siba Culture period (Flad et al. fied later as a pottery of Western Zhou (Yang 1963). forthcoming). This investigation, together with the tests Similar problems also occurred at the data of the followed up, has made it clear that the wheat evidence Zhaojialai site. Though the date is correct (contemporary from the Donghui Mound site are most likely to be left with the Longshan period), taxonomic identification is by the Siba Culture people ca. 3500 BP. still questionable. According to the report, the so-called Relatively, the data from the sites in Xinjiang are wheat remains are most likely to be the impressions left more reliable. The wheat remains found in these sites by the straws tempered within the mud for building the were well preserved, thanks to the arid condition of walls (Zhongguo 1988). However, straw remains can- desert environments, which ensured a precise taxo- not be easily used as hard evidence for taxonomic iden- nomic identification. The dates of these plant remains tification even when they are in fresh and living state, were also unquestionable, and all of them were dated let alone the dried-out impressions. to ca. 3500 BP. The most controversial data are the wheat remains New Data of Wheat Remains by Flotation recovered from the Donghui Mound site. They were first collected and studied in 1985 by Li Fan, a famous Since the beginning of this century, flotation has been agronomist in China. The wheat remains, identified as widely applied in Chinese archaeological fieldworks. To two species of Triticum aestivvum and T. compactum, date, wheat has been discovered at more than twenty were subsequently radiocarbon dated to ca. 5000 BP (Li archaeological sites through flotation. Most of them are 1989). The taxonomic identification is reliable; but the dated to before 3000 cal. BP and located in the areas date is highly suspicious due to the unclear context of along the Yellow River in North China. We divide these dating materials, because Li was not familiar with ar- areas into three regions, which are the Haidai region, chaeology and nobody knew how and from what kind the Central Plains region and the Northwest region, based of provenance the wheat remains were collected. on ecological characteristics and archaeological classi- By contrast, professional archaeologists dated the fications (Figure 1). Donghui Mound site to the Siba Culture period through 1. The Haidai region a regular archaeological excavation in 1987 (Gansu The Haidai region is a spatial concept for archaeo- Sheng and Jilin 1998). The Siba Culture represents an logical classification in China. In archaeological litera- early Bronze Age culture widely distributed along the ture it refers to the distribution areas of the Dawenkou Hexi Corridor, and dated to 3900–3500 cal. BP, which Culture and the Shandong Longshan Culture, including is about 1000 years later than that given by Li. However, Shandong Province, northern parts of Anhui and Jiangsu the two samples in the excavation report made the dat- Provinces (Luan 1997). The early wheat remains have ing issue even more ambiguously complicated. One of been identified through flotation from five archaeologi- them is the charcoal sample unearthed from the second cal sites in this region: Liangchengzhen in Rizhao layer of a trench (No. 87MDTG②) and has been radio- (Crawford et al. 2004), Jiaochangpu in Liaocheng (Zhao carbon dated to 3770 ± 145 cal. BP (calibrated), and 2004), Zhaojiazhuang in Jiaozhou (Wang 2007), this result falls well in the range of the Siba Culture pe- Daxinzhuang in Jinan (Chen 2007), and Zhaogezhuang riod as indicated above. The other one, however, is a in Yantai (Jin et al. forthcoming). sample of wheat remains dated to 4230±250 BP with- It is noteworthy that the archaeological wheat evi- out clear provenance, an unacceptable time span for con- dence from the sites of Liangchengzhen, Jiaochangpu ducting dendro-calibration, coincided with that given by and Zhaojiazhuang were primarily the wheat remains Li Fan. from the Longshan Period, dating to 4600–4000 cal. BP. Recently, experts from home and abroad conducted These data are not only the earliest but also the most a joint investigation to the Donghui Mound site. Soil reliable wheat evidence found in China at moment, be- samples collected from which were floated, and barley cause the sites have been excavated scientifically and and wheat remains have been recovered and identified. multidisciplinary studies were carried out during the 2 Chinese Archaeology Zhao Zhijun excavations. 2. The Central Plains region The Central Plains region is lo- cated at the core of the early Chi- nese civilization areas, encompass- ing the northern and central parts of Henan Province and southern parts Mongolian Highland of Shanxi and Hebei Provinces. The Central Plains region covers the major distribution areas of the Iranian Plateau Henan Longshan Culture. As a part of the archaeological project entitled “Exploration on the Origin of Chi- Indian Subcontinent nese Civilization”funded by the Ministry of Sciences and Technologies, we have conducted flotation work on many important Figure 1. The eastward spread of wheat into China sites in the Central Plains region. 1. West Asia 2. The Bronze Age cultures in the Eurasian steppe (2a. Andronovo, Some of these sites yielded the early 2b. Afanasevo) 3. Northern Zone 4. The Haidai region 5. The Central Plains wheat remains, such as Wadian in region 6. The Northwest region Yuzhou, Erlitou in Yanshi, Wangchenggang in Dengfeng, Huizui in Lingbao, 3. The Northwest region Xinzhai in Xinmi, Shangcheng (the site of an early Shang Archaeologically, the Northwest region in China re- city) in Yanshi, and the Yin Ruins in Anyang (Zhao fers to the upper Yellow River valley (Shaanxi, Ningxia, 2007; Zhao and Fang 2007). Apart from these sites re- the eastern parts of Gansu and Qinghai), the Hexi Corri- lated to the above project, it is reported that the early dor (western part of Gansu), and northern part of wheat remains were found from the Xijincheng site at Xinjiang.