an analysis of chinese data on root and tuber crop production

An Analysis of Chinese Data on Root and Tuber Crop ProductionAuthor(s): Bruce StoneSource: The China Quarterly, No. 99 (Sep., 1984), pp. 594-630Published by: Cambridge University Press on behalf of the School of Oriental and African StudiesStable URL: http://www.jstor.org/stable/653243 .

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An Analysis of Chinese Data on Root and Tuber Crop Production

Bruce Stone

Soon after the People's Republic of China resumed publishing economic data series in the late 1970s it became clear that current definitional conventions for statistical categories often differed from those of the 1950s. For example, tractor stock, in standard 15 horse-power units from the 1950s, was recorded in series linked with current physical unit data. Sporadic efforts have been made clearly to define categories in different periods, pin down transition dates, and occasionally develop consistent series. In some instances, Chinese statistical organizations have produced series making adjustments for specific inconsistencies in previously published data. Soybeans, for example, are now included in the entire official series for foodgrain production and sown area from 1949 to the present; they were previously excluded from 1949-57 data. Articles by Walker and by Field and Kilpatrick' were among attempts to correct for this inconsistency, considerably pre-dating the official published adjustment. At around the same time several researchers2 noted that roots and tubers were valued at one-fourth natural weight in the 1950s, but one-fifth under current convention.3 For a few years the transition date was open to question and arguments were tendered in support of 1977, 1970 and 1964. Members of a United States Department of Agriculture delegation to China seem to have ended the debate by simply asking their Chinese hosts. They were told categorically that the official change was in 1964, although it is always possible that the effective date differed somewhat among reporting units or even among provinces. Some four years later the date was confirmed in the 1983 Statistical Yearbook.4 Although thus far Chinese statistical series have not amended the 1949-63 data for consistency with 1964-82 in this respect, non-Chinese attempts have been made to incorporate this adjustment linking current and 1950s foodgrain

1. Kenneth R. Walker, "Provincial grain output in China, 1952-57: a statistical compilation," Research Notes and Studies, No. 3 (London: Contemporary China Institute, School for Oriental and African Studies, University of London, 1977); Robert Michael Field and James A. Kilpatrick, "Chinese grain production: an interpretation of the data," The China Quarterly (June 1978), pp. 369-84.

2. Among these were Field and Kilpatrick, Audrey Donnithorne, Kenneth Walker and Bruce Stone.

3. It should be noted in passing that Chinese conception of "foodgrain equivalence" differs from that of the Food and Agriculture Organization of the United Nations (FAO). China divides all root and tuber crops by five to approximate grain equivalent weight, although data for root and tuber crops converted as such now exclude cassava. FAO estimates grain equivalent weight by applying differential factors to natural weight statistics for each root and tuber crop, based on comparative data on caloric content by unit weight: white potatoes-20%; sweet potatoes-25 %; cassava-30.3%.

4. Zhongguo Guojia Tongjiju (Statistical Bureau of China), Zhongguo tongji nianjian-1983 (Statistical Yearbook of China-1983) (Xianggang: Xianggang jingji daobao shechuban, 1983), p. 583.



Chinese Data on Root and Tuber Crop Production 595

production data at the national and provincial levels.5 Table 1 shows the reconstructed official root and tuber crop series (in terms of natural weight) implied by a 1964 accounting shift.

While such refinements are quite trivial for many purposes, they are much less so for others. And, although changes in statistical definitions are rarely simultaneous and complete, and diversity in statistical practice is more common than consistency, rough adjustments for the major shifts and inconsistencies are sometimes worth attempting. Adjusting for the definitional shifts affects our notion of the rate of foodgrain production growth in major root and tuber crop and soybean producing provinces. It also has considerable impact on our appreciation of rapid yield growth of root and tuber crops as an aggregated category, and of dramatic shifts in sown area affecting specific root and tuber crops.

Before outlining these shifts, some additional discussion on definitional consistency related to root and tuber crops is in order. Cassava, taro sweet potatoes and yams are all tuberous root crops. The white potato is classified as a tuber crop since the potato plant has wholly separate roots which are not tuberous. Etymologically, the aggregate statistical classification used most commonly by the Chinese, shulei, may be most closely approximated by the term "tubers and tuberous root crops." But the distinctions are somewhat confused from the standpoint of morphology, common use and statistical practice.

White potatoes (malingshu) and sweet potatoes (ganshu) have always been classified as shulei. Yams (shuyu or shanyao) are tuberous roots, scientifically and by traditional statistical practice, but like the (non- tuberous) winter radish (dongluobo or hongluobo), they are not now explicitly included among shulei, although production levels may approach those of taro, even among taro growing provinces.6 Taro (yu), although a tuberous root, never carries the generic character shu, but sometimes has been statistically included with shulei, and the term "yu," itself, occasionally is used to refer to root and tuber crops in general. For example, hongyu (literally, "red taro") and shanyu (literally, "mountain taro") are actually sweet potatoes. Shanyu is sometimes used to refer to all sweet potatoes. Yangyu (literally, "foreign taro") means white potato.' To

5. See, e.g. Bruce Stone, "China's 1985 foodgrain production target: issues and pros- pects" in Anthony M. Tang and Bruce Stone, Food Production in the People's Republic of China, Research Report No. 15 (Washington, D.C.: International Food Policy Research Institute, 1980), pp. 88 and 157; for efforts at establishing consistency among provincial data see Kenneth R. Walker, "China's grain production 1975-80 and 1952-57: some basic statistics," The China Quarterly, No. 86 (June 1981), pp. 241 and 243-47.

6. According to the survey of 16,786 farms directed by John Lossing Buck between 1929 and 1933, 0-2? of cropped area was sown with taro and 0- 1? with yams. South China, where taro and yam cultivation is most extensive, was somewhat under-represented in Buck's sample. But, of course, other areas where these crops are not grown at all (e.g., the Manchurian provinces of the north-east and Inner Mongolia) were completely excluded [John Lossing Buck, Land Utilization in China (Study) (Nanking: Nanking University Press, 1973)].

7. See e.g. Anhui Shifan Daxue Dilishi (Anhui Normal University, Geography Department) (ed.), Anhui nongye dili (Agricultural Geography of Anhui) (Hefei: Anhui kexue jishu chubanshe, 1980), pp. 36 and 40; and Zhongguo Kexueyuan Chengdu Dili Yanjiusuo (Chinese Academy of Sciences, Chengdu Institute of Geography) (ed.), Sichuan nongye dili (Agricultural Geography of Sichuan) (Chengdu: Sichuan renmin chubanshe, 1980), p. 71;



596 The China Quarterly

Table 1: Official Chinese Estimates of Total Root and Tuber Production, Sown Area and Yields, 1949-82

Production Yield Sown Area

('000 metric tons (metric tons ('000 hectares) natural weight) per hectare)

Year A B A B A B

1949 7,011 7,011 49,225 39,370 7-02 5-62 1950 7,696 7,696 61,950 49,560 8-05 6-44 1951 8,286 8,286 70,000 56,000 8-45 6-76 1952 8,688 8,688 81,625 65,302 9-40 7-52 1953 9,016 9,016 83,275 66,610 9-24 7-39 1954 9,781 9,781 84,900 67,922 8-68 6-94 1955 10,054 10,054 94,475 75,586 9-40 7-52 1956 10,992 10,992 109,250 87,404 9-94 7-95 1957 10,495 10,495 109,600 87,676 10-44 8-35 1958 15,382 15,382 163,625 130,900 10-64 8-51 1959 12,289 12,289 119,075 95,260 9-69 7-75 1960 13,531 13,531 101,750 81,400 7-52 6-02 1961 12,026 12,026 108,650 86,920 9-03 7-23 1962 12,171 12,171 117,225 93,780 9-63 7-71 1963 11,899 11,899 106,975 85,560 8-99 7-19 1964 11,257 11,257 100,625 100,625 8-94 8-94 1965 11,175 11,175 99,300 99,300 8-89 8-89 1966 11,647 11,647 112,625 112,625 9-67 9-67 1967 10,716 10,716 112,150 112,150 10-47 10-47 1968 10,307 10,307 111,425 111,425 10-81 10-81 1969 10,447 10,447 120,575 120,575 11-54 11-54 1970 10,717 10,717 133,375 133,375 12-45 12-45 1971 10,405 10,405 125,325 125,325 12-04 12-04 1972 10,841 10,841 122,575 122,575 11-31 11-31 1973 11,306 11,306 157,775 157,775 13-95 13-95 1974 11,069 11,069 141,200 141,200 12-76 12-76 1975 10,969 10,969 142,825 142,825 13-02 13-02 1976 10,366 10,366 133,300 133,300 12-86 12-86 1977 11,229 11,229 148,350 148,350 13-21 13-21 1978 11,796 11,796 158,700 158,700 13-45 13-45 1979 10,952 10,952 142,300 142,300 12-99 12-99 1980 10,153 10,153 143,625 143,625 14-15 14-15 1981 9,621 9,621 129,850 129,850 13-50 13-50 1982 9,363 9,363 133,400 133,400 14-25 14-25

Notes: Current official root and tuber crop (shulei) data include only sweet and white potatoes.

They exclude around 3 million tons of cassava, typically sown on 350-500,000 hectares. The definition may be inconsistent with earlier data. The 1950s Chinese publications treat cassava as shulei. Less than one million tons of cassava was probably grown on around 100,000 hectares in the 1950s. Taro was included among Guangxi data for shulei in an agricultural geography published as late as 1980, but it was officially excluded in a 1981 Ministry of Agriculture publication and may have been excluded as early as 1979. Current taro production and sown area are unknown but in Buck's 1929-33 survey, it was planted on

0-2% of total cropped area. Series A are official figures as implied by recent official statistical




publications. Series B are reconstructed official figures based on the hypothesis that the official accounting convention was shifted from one-fourth to one-fifth natural weight in 1964. Sources.

Zhongguo Nongyebu, Jihuaju (Chinese Ministry of Agriculture, Bureau of Planning), Zhongguo yu shijie zhuyao guojia nongye shengchan tong/i ziliao huibian (A Collection of Statistical Data on the Agricultural Production of China and Other Major Countries) (Beijing: Nongye chubanshe, 1958); Zhongguo Guojia Tongjiju (State Statistical Bureau of China), Zhongguo tongji nianjian - 1981 (Statistical Yearbook of China - 1981) (Xianggang: Xianggang jingji daobao shechuban, 1982); Zhongguo Tongjiju Guojia, Zhongguo tongji zhaiyao 1983 (1983 Statistical Abstract of China) (Beijing: Tongji chubanshe, 1983); James H. Cock and Kazuo Kawano, "Cassava in China," unpub. trip report, International Center for Tropical Agricultural Research (CIAT). Correspondence, 24 June 1983. Zhongguo Kexueyuan (Chinese Academy of Sciences), Zhongguo nongye dili zonglun (A General Discussion of China's Agricultural Geography (Beijing: Kexue chubanshe, 1980); Zhongguo Tongjiju, Zhongguo tongji nianjian - 1983; Guangxi Nongye Dili Bianxiezu (Guangxi Agricultural Geography Editorial Board), Guangxi nongye dili (Guangxi Agricultural Geography) (Nanning: Guangxi renmin chubanshe, 1980); Yan Shen (ed.), Nongye tongji (Agricultural Statistics) (Beijing: Nongye chubanshe, 1981); J. L. Buck, Land Utilization in China (Study) (Nanking: Nanking University Press, 1937).

Production figures in Column A were calculated from official data appearing in Zhongguo Guojia Tongjiju, Zhongguo tongji nianjian - 1983, pp. 162 assuming that the published data were valued at one-fifth natural weight throughout. The sown area data were converted from Chinese unit data on p. 155. The yield data were calculated accordingly and are consistent with yield data found for 1949, 1952, 1957, 1962, 1965 and 1978-82, on p. 171.

Column B production figures for 1949-63 were recalculated from the same source assuming that the data for those years were directly adopted from earlier materials actually valuing tubers at one-fourth natural weight. The 1949-63 yield data were recalculated accordingly. The 1964-82 data are identical to those appearing in Column A.

confuse matters further, baishu (literally, "white potato") is actually a term for sweet potato, not white potato. The most common terms for sweet potato other than ganshu (literally, "sweet potato"), are probably hongtiao (literally, "red creeper") and hongshu ("red potato").8

The proliferation of names for sweet potato is hardly surprising in China, the world's most extensive and productive cultivator of the crop. Several of the names no doubt originally denoted specific varieties common to particular regions. But the proliferation of names extends equally to the white potato, which enjoys a somewhat shorter and less complex history and narrower genetic base in China than does the sweet potato.9 In addition to yangyu, for example, tudou (literally, "dirt bean")

and Henansheng Nongyeting Henansheng Nonglin Kexueyuan (Henan Province Agricul- tural Office, Henan Academy of Agriculture and Forestry Sciences) (eds.), Hongshu (Sweet Potato) (Zhengzhou: Henan renmin chubanshe, 1980), p. 1.

8. See, for example, Guangxi Nongye Dili Bianxiezu, Guangxi nongye dili, pp. 64, 68 and 76; and Zhongguo Kexueyuan Chengdu Dili Yanjiusuo, Sichuan nongye dili, pp. 71-72 and 82-83; and Henansheng Nongyeting Henansheng Nonglin Kexueyuan, Hongshu.

9. Sweet potatoes probably entered China originally from India and Burma through Yunnan Province. Two books published, respectively, in 1563 and 1574 discuss sweet potatoes in Yunnan. In 1594 overseas Chinese troops brought sweet potatoes back to the Fujian Province coast. There seem to be other distinct contacts in the mid 17th and mid 18th centuries. Fujiansheng Nongyeting (Fujian Province Agricultural Office), Ganshu (Sweet Potato) (Fuzhou: Fujian kexue jishu chubanshe, 1980), p. 3; and Henansheng Nongyeting Henansheng Nonglin Kexueyuan, Hongshu, pp. 1 and 2. The earliest recorded mention of white potatoes in China was in a book published in Fujian Province in 1700 which described potato cultivation in northern Fujian and southwestern Zhejiang Provinces: Heilongjiang Nongye Kexueyuan, Keshan Nongye Yanjiusuo (Heilongjiang Province Academy of Agricultural Sciences), Malingshu zaipei jishu (White Potato Cultivation Technology) (Beijing: Nongye chubanshe, 1982), p. 7.




is a common term for white potato in several provinces, although malingshu ("horse bell potato") is most common (see Table 2).

Table 2: Chinese Names for Various Root and Tuber Crops

Broad Chinese Literal Category Name Translation Region of Popularity

Sweet potato ganshu sweet potato general throughout China

hongshu red potato general, especially south and central China

hongtiao red creeper west central China, e.g. Henan, Sichuan

baishu white potato central China, e.g. Henan, Anhui

shanyu mountain taro central China, e.g. Henan, Anhui

hongyu red taro west central China, e.g. Henan

digua ground melon north and central China, e.g. Henan, Hebei, Shandong

fanshu* abundant potato Henan and elsewhere

White malingshu horsebell potato general throughout China potato tudou earth bean general, but esp. north-east

China and Yunnan yangyut foreign taro north-west and south-west

China yang- foreign mountain north-west and south-west

shanyut taro China shanyaol mountain medicine north-west China, esp.

Shanxi and Inner Mongolia shan- mountain medicine north-west China, esp.

yaodan$ egg Shanxi and Inner Mongolia yangshan- foreign mountain north-west China, esp.

yaof$ medicine or Shanxi and Inner Mongolia foreign yam

didan ground egg north China, esp. Hebei, Tianjin and Beijing

didou ground bean north China, esp. Hebei, Tianjin and Beijing

hela'nshu Dutch potato south-east coastal China, e.g. Guangdong and Fujian

zhaowashu Javanese potato south-east coastal China, e.g. Guangdong and Fujian

aierlanshu Irish potato south-east coastal China, e.g. Guangdong and Fujian

fanzaishu* potato with many south-east coastal China, e.g. children Guangdong and Fujian

gantong? dry comrades south-east coastal China, e.g. Guangdong and Fujian

tumao earth mortise south China




Table 2: (cont.)

Broad Chinese Literal

Category Name Translation Region of Popularity

White yangyunait foreign taro Zhejiang potato yangfan- foreign multiple Zhejiang (cont'd) shu*f potato

fanrenshu* potato for many Wenzhou people

fanguicigu* arrowhead of many Guangxi spirits

xiangyu fragrant taro south and central China tuyu earth taro south and central China fanyu* multiple taro south and central China yangyu taro of the sun south and central China

Yam shuyu|| potato yam general shanyao II mountain medicine general

Cassava mushu tree tuber general Taro yu taro general Winter dongluobuo winter radish general

radish hongluobuo red radish general, archaic

Notes: Most of the terms cannot be exactly placed geographically. Several are now used in a

variety of mutually distant locales. Some are unknown in parts of the regions or provinces indicated. This is merely an attempt to give a rough indication of regions in which the terms may be used and the broad classification of root or tuber crop to which they refer.

* The character fan normally means "multiple" which is quite appropriate for the white potato with its multiple tubers from a single plant. But fanshu clearly refer to sweet potato. Here the appropriate translation may be "abundant" or "fairyland."

t Except in the case of the last white potato term, the character for yang denotes "ocean," hence "from across the ocean" or "foreign."

I Shanyao generally means yam, but in the north-west, the term refers to a white potato originally called yangshanyao or "foreign yam" and eventually shortened to shanyao since yams are not grown in that region of the country.

? It is possible that the water radical has been dropped from the second character. The term may originally have been gandongshu or "dry cave potato."

ii These terms refer to the Chinese yam (Dioscorea). Sources:

Anhui Shifan Daxue Dilishi (ed.), Anhui nongye dili; John Lossing Buck, Land Utilization in China (Atlas) (Nanking: University of Nanking Press, 1937); Fujiansheng Nongyeting, Ganshu; Guangxi Nongye Dili Bianxiezu, Guangxi nongye dili; Heilongjiangsheng Nongye Kexueyuan Keshan Nongye Kexue Yanjiusuo, Malingshu zaipei jishu; Henansheng Nongyeting Henansheng Nonglin Kexueyuan (eds.), Hongshu; Liang Rencai, Guangdong jingli dili (Economic Geography of Guangdong) (Beijing: Kexue chubanshe, 1956), pp. 19, 25, 29, 33, 102; Zhongguo Kexueyuan Chengdu Dili Yanjiusuo, Sichuan nongye dili.

The principal concerns here are not the varieties, nor the variety of names for any of the crops, but: (1) whether all varieties of sweet potato are included under the category designated by the name of the most common regional variety; (2) whether shulei, as a statistical category, always includes all root and tuber crops officially designated as such, or whether coverage varies from province to province (or among smaller geographic units); and (3) whether the root and tuber crops officially included among shulei have changed over time.




It is virtually impossible to be completely confident about the first two considerations. For example, one cannot always be sure that statistics for hongtiao in Sichuan, hongshu in Guangxi, or shanyu in Anhui include all sweet potatoes and not just the dominant varieties in these provinces; nor can one be sure that hongtiao, hongshu and shanyu are not occasionally being used as broader generic terms, to represent all shulei or even all roots and tubers. For example, in one provincial publication on sweet potatoes, inter-provincial and national statistical comparisons for hongshu were clearly taken from shulei data and are an inappropriate reflection of comparisons for sweet potatoes alone.'" But for the most part in major statistical publications, these worries are relatively minor as far as field crops are concerned. The 1979-82 provincial statistics for shulei in Sichuan, for example, where both white and sweet potatoes are grown in abundance, considerably exceed the 1977 data for hongtiao (sweet potato)."1 In cases where "sweet potato" is the specified root and tuber category among the pre-1979 foodgrain data, other roots and tubers classified as "foodgrains" are presumably captured under "other foodgrains" along with minor coarse grains and field pea and bean crops other than soybeans.

There is definitely a distinction between field crops and garden crops. The foodgrain category shulei includes tuberous roots and tuber crops cultivated as field crops and seems to exclude plantings among vegetable acreage.'2 This certainly applies to the suburban vegetable communes, and may apply in principle to private plots. But private plots, in the past, were typically subject to one of three different planning principles: (1) complete management control resting with the respective families; (2) planned cultivation on a team or even commune basis, but clearly a separate process and separate cropping from that exhibited with collective lands; and (3) complete integration with collective land planning. The result was that private plot cultivation more closely resembled field

10. Henansheng Nongyeting Henansheng Nonglin Kexueyuan, Hongshu, p. 5. 11. According to Zhongguo Kexueyuan Chengdu Dili Yanjiusuo, Sichuan nongve dili,

p. 72, area sown with hongtiao in 1977 was 18-9 million mu and production was 8-34 billion jin (on a grain equivalent basis). Area sown with shulei was 29-852 million mu in 1979 while production was 11-62 billion jin. See, He Gang et al. (eds.), Zhongguo Nongyebu (Chinese Ministry of Agriculture), Zhongguo nongye nianjian, 1980 (Agricultural Yearbook of China, 1980) (Beijing: Nongye chubanshe, 1980), p. 105.

12. E.g. according to crop-specific statistics in Luo Hanxian et al. (eds.), Zhongguo nongye nianjian, 1981, p. 26, Shanghai Municipal Area grew only 200 hectares of root and tuber crops in 1980. Yet as late as June 1977, The Vegetable Farming Systems Delegation organized by the United States National Academy of Sciences was given data indicating that about 20o of Shanghai's vegetable area was sown with root and tuber crops [Donald L. Plucknett and Halsey Beemer (eds.), Vegetable Farming Systems in the People's Republic of China (Boulder: Westview, 1981)]. According to a 1959 distribution, more than 1/4 of these plantings were likely to be radishes and turnips, never included among "foodgrain" roots and tubers [Shanghai Nongye Yanjiusuo, Shanghai sucai pinzhongzhi (Shanghai: Shanghai nongye yanjiusuo, 1959)]. If "foodgrain" root and tuber crops sown among vegetable plantings were included in crop-specific root and tuber data, the above information would imply that less than 1500 hectares of land in Shanghai Municipal Area is sown with vegetable crops. This is surely a considerable underestimate. The 200 hectares of "foodgrain" root and tuber crop plantings therefore refer only to field crops and not to roots and tubers cultivated among vegetable plantings.




cultivation than vegetable gardening for the third, and a portion of the second category of plots. Root and tuber crops grown as field crops on private plots but planned collectively, would then be likely to appear among shulei statistics, although potatoes cultivated along with vegetable crops on the individually planned plots may not be included. Data appearing in the 1980 Agricultural Yearbook suggest that foodgrain cultivated on private plots (and included among "foodgrain" statistics) comprised almost 4-9 per cent of the national total in 1979.13 No doubt the proportion of root and tuber crops cultivated among private plot vegetable plantings and not included in shulei statistics is changing owing to: (1) the enlargement of plots in some localities; (2) the increased individual autonomy over plots in many localities; and (3) the partial blurring of distinctions between private plots and collective lands organized under most forms of the responsibility system.

Another way to distinguish between root and tuber crops which are included under shulei from those that are not is to ask whether the crop is consumed as a staple food crop or as a vegetable; or even whether local plantings are sufficiently extensive that tax and quota deliveries of the crop occur. This may explain why in Guangxi at least, taro was recently included among shulei (it is still of great local importance to several south China minority groups, such as the Yao of northern Guangdong), while yams and winter radishes, which may now be at most a minor supplemen- tary staple, have long ceased to be explicitly listed as shulei. Of course this does not guarantee that taro is everywhere included, and yams and winter radishes everywhere excluded from shulei data or that there has not been a change in coverage since the commencement of shulei data as an aggregated "foodgrain" category. In fact it now seems clear that shulei data are now intended to include only sweet and white potatoes and exclude taro, cassava and other minor root and tuber crops included among 1950s shulei data. These root and tuber crops other than sweet and white potatoes accounted for 4-5 per cent of shulei production and sown area during the 1950s (Table 3).

Cassava (mushu or "tree tuber") is a tuberous root crop cultivated almost exclusively in Guangdong and Guangxi.14 The Economic Geo- graphy of South China, published in 1959, explicitly treats cassava as shulei, which in turn, were officially classified as foodgrains, occasionally as part of "miscellaneous grains"'9 (although shulei were not included as such in some 1950s compendia and in some areas). A General Discussion of China's Agricultural Geography, published in 1980, described cassava as the third ranking root or tuber crop in China, although it does not specify

13. He Gang et al. (eds.), Zhongguo Nongyebu, Zhongguo nongye nianjian, 1980, p. 102. 14. Zhongguo Kexueyuan, Dili Yanjiusuo, Jingji Dili Yanjiushi (Chinese Academy of

Sciences, Institute of Geography, Economic Geography Research Room), Zhongguo nongye dili zonglun (A General Discussion of China's Agricultural Geography) (Beijing: Kexue chubanshe, 1980), p. 129. The source verifies that virtually all of China's cassava is grown in Guangdong and Guangxi.

15. Sun Jingzhi (ed.), Huanan dichu jingji dili (Economic Geography of South China) (Beijing: Kexue chubanshe, 1959).



Table 3: Official Estimates of Production, Sown Area and Yields for Sweet Potatoes, White Potatoes and "Other Roots and Tubers," 1952-57

Sown Area Production Yield

Sweet White Other Roots Sweet White Other Roots Sweet White Other Roots Potatoes Potatoes and Tubers Potatoes Potatoes and Tubers Potatoes Potatoes and Tubers

Year (million hectares) (million metric tons, natural weight) (metric tons natural weight/hectare)

1952 6-5093 1-7732 0-4052 50-238 12-384 2-680 7-719 6-984 6.614 1953 6-8317 1-7275 0-4566 52-924 10-392 3-294 7-746 6-015 7,214

1954 7-4964 1-7992 0-4853 53-920 10-758 3-244 7-194 5-979 6,685 1955 7-7620 1-8567 0-4352 60-560 12-238 2-788 7-803 6-591

6"406 1956 8-2798 2-1238 0-5882 70-550 13-136 3-718 8-520 6-186 6-321 1957 7-9273 2-0641 0-5033 70-280 13-500 3-896 8-865 6-540

7.741

Notes: "Other roots and tubers" consist of all crops included among root and tuber crop (shulei) statistics during the 1950s except for the major root and tuber crops (sweet

potatoes and white potatoes). "Other roots and tubers" consist of cassava, taro, and other minor roots and tubers such as "mao" potatoes. It is possible that they include some more important root crops typically considered vegetables such as yams and winter radishes. Sources:

These figures are based on data appearing in Zhongguo Nongyebu, Jihuaju, Zhongguo yu shijie zhuyao guojia nongye shengchan tong/i ziliao huibian. The figures for sweet potatoes and white potatoes were converted directly from Chinese unit data in the source and the production data were converted to natural weight. To arrive at the figures for "other roots and tubers" sown area and production data for sweet potatoes (pp. 26 and 28) and white potatoes (pp. 29 and 31) were deducted from data for shulei (pp. 23 and 25). The remainders were converted to international units and (in the case of production data) to natural weight. Yields were calculated accordingly.

C)

Ct




cassava among tabular materials.16 But a Chinese statistical delegation visiting the Food and Agriculture Organization (FAO) of the UN at the end of 1979 indicated that their current concept of shulei included only sweet and white potatoes, while cassava, taro and turnips were considered vegetable crops.17 The classification is clearly applicable to international trade data since no residual component of official grain export data could accommodate the rapid rise in cassava exports in 1980,18 whereas "vegetables" has appeared as a new voluminous export category in the 1981 Statistical Yearbook of China.19 But it remained to be verified whether official estimates of national production and cultivation have ever in- corporated this definition. It is quite common, after all, that representative officials simply do not know the current official convention, must less the diversity of practice.

A 1982 delegation from the International Center for Tropical Agricul- ture (CIAT) was given data which indicated that production of cassava was 3-0 millions tons of fresh root (natural weight), from 350,000 hectares of land, with Guangdong accounting for 200,000 hectares.20 The Agricul- tural Geography of Guangxi implied 168,331 hectares of cassava in Guangxi for 1976.21 Table 4 shows that according to 1979 official data for

Table 4: Area Sown with Vegetable Crops, "Other" Economic Crops and Unspecified "Other" Crops in Guangdong and Guangxi, 1979 ('000 ha.)

Guangdong Guangxi

Vegetable crops 182-00 68-07 Green fodder crops 40-27 36-67 Unspecified "other" 36-27 15-80

crops* Other economic cropst 214-60 193-67

Notes: *"Unspecified other crops" is a residual category formed after data for vegetables,

melons, green fodder crops and green manure crops are deducted from data for "other farm crops," which excludes grain crops and economic crops.

t "Other economic crops" is a residual category formed after data for cotton, all oilseeds, all bast fibres, all sugar crops, all tobacco crops and medicinal herbs are deducted from data for "total economic crops." Source:

He Gang et al. (eds.), Zhongguo Nongyebu, Zhongguo nongye nianjian, 1980.

16. Zhongguo Kexueyuan, Dili Yanjiusuo, Zhongguo nongye dili zonglun. 17. Leroy Quance, Director, Statistics Division, Food and Agriculture Organization of

the United Nations, correspondence, 5 July 1983. 18. Xue Muqiao et al. (eds.), Zhongguo jingji nianjian (1982) (Almanac of China's

Economy (1982)) (Beijing: Jingji guanli zazhi shechuban, 1982), p. VII-47. 19. Zhongguo Guojia Tongjiju, Zhongguo tongji nianjian-1981, p. 394. 20. Cock and Kawano, "Cassava in China," pp. 1-2. 21. Guangxi nongye dili indicates that area planted with cassava in 1976 was 2-14% and

foodgrains (excluding cassava) 82-66% of total sown area (p. 64). Total foodgrain sown area in 1976 was 4,334,666 hectares (summed from data for constituent districts on p. 70).




Guangdong and Guangxi, cassava-sown area components of 200,000 and 150,000 hectares, respectively, could not have been included among the categories for "vegetable crops," "green fodder crops" or unspecified "other crops" for the two provinces, although the "other economic crop" category is sufficiently large in both cases barely to accommodate cassava acreage if other components of the category are very minor. In fact, this is exactly the classification for cassava appearing in The Agricultural Geography of Guangxi which was published in 1980. In this source, sweet potatoes, white potatoes and taro are designated as shulei (and hence foodgrains), while cassava is listed as an economic crop. In tabular material, however, hongshu (sweet potatoes) have a specific classification and white potatoes and taro are presumably included among "other miscellaneous grains."22 Finally, a Ministry of Agriculture sponsored compendium published in May 1981, Agricultural Statistics, clearly stipulates that among cultivation data, only sweet potatoes and white potatoes are included among shulei and hence foodgrains. Taro is considered a vegetable and cassava is an "other economic crop."23 The 1983 Statistical Yearbook confirmed that shulei statistics are comprised entirely of sweet and white potatoes.24

One must conclude that the root and tuber crop inclusion among 1950s official data is not consistent with current practice. For want of more information, one might assume that the transition for cassava was 1964 (coinciding with the accounting shift from one-fourth to

one-fifth'natural weight) or 1976 (subsequent to a major survey informing A General Discussion of China's Agricultural Geography and coinciding with one of several significant declines in official root and tuber sown area), but the actual date is open to question. In any event, it was likely to be around or before 1976-77, the dates for which the data in the Agricultural Geography of Guangxi appeared. As for taro, the transition date would appear to be 1981, since the Agricultural Geography of Guangxi was published in 1980 and Agricultural Statistics, in 1981, but it could have occurred anywhere in the 1976-81 period, and probably preceded the 1979 Chinese statistical delegation visit to FAO. The year 1979 seems a reasonable choice. Of course it is always possible that Guangxi (and perhaps Guangdong) continued to classify taro among shulei even after the official transition.

Table 5 shows that the implications for assessing long-term foodgrain production growth, of the shift in crop inclusion plus the shift in foodgrain equivalence convention are minor but measurable. The average annual 26-year production growth rate implied by the consistent reconstructed official figures (Series B) for the two periods is 2-54 per cent as opposed to 2-42 per cent implied by official figures as they appear. The sown area reconstructions imply a slightly slower decline in foodgrain sown area since 1956 than do the official data. But before too much is made of these lower reconstructed official production and area figures for

22. Ibid. pp. 64, 76 and 83. 23. Yan Shen (ed.) Nongye tong/i, p. 105. 24. Zhongguo Guojia Tongjiju, Zhongguo tong/i nianjian - 1983, p. 583.




Table 5: Consistent Reconstructed Official Estimates of Foodgrain Produc- tion and Sown Area, 1952-82

Sown Area Production

(million hectares) (million metric tons)

Year A B A B

1952 123-979 123-573 163-915 160-114 1953 126-627 126-180 166-830 162-838 1954 128-995 128-510 169-515 165-471 1955 129-839 129-404 183-935 179-600 1956 136-339 135-750 192-745 187-632 1957 133-633 133-130 195-045 184-401

1979 119-263 119-263 332-115 332-115 1980 117-234 117-234 320-555 320-555 1981 114-958 114-958 325-020 325-020 1982 113-396 113-396 353-425 353-425

Notes: The A series are "foodgrain" data converted from Chinese units as they appear in current

official Chinese statistical publications. However the 1950s data appear to be inconsistent with the 1979-82 figures. The current official Chinese definition of "foodgrains" includes soybeans, sweet potatoes and white potatoes (as well as rice, wheat, coarse grains and pulses) but excludes cassava, taro and other minor root and tuber crops. Sweet potato and white potato production are valued at one-fifth natural weight among the production statistics. The B series include recalculations of the 1952-57 official data to exclude cassava, taro and minor roots and tubers and value all sweet and white potato production at one-fifth rather than one-fourth natural weight. Sources:

The A series are converted directly from Chinese unit data for foodgrain sown area production appearing in Zhongguo Guojia Tongjiju, Zhongguo tong/i nianjian - 1983, pp. 154-62. The B series uses the A series as a base, deducts total root and tuber crop data from pp. 155 and 162 of the same publication, then adds back data for sweet potatoes and white potatoes only, from Table 3, but valuing the production figures at one-fifth natural weight.

the 1950s, it is important to note that the official data for several of these years have long been criticized as underestimates.

The most thorough examination of the 1950s foodgrain data in recent years was conducted by Thomas Wiens, around 1975.25 Wiens concluded that the 1949-55 official production and sown area data (especially for the early years) were probably underestimated, but that the 1956 data, if anything were over-estimated. He did not intend a revision of the 1957 official data, but his figures for that year are flawed by some transcription errors appearing among the secondary source materials he employs. Wiens' revisions appear as Series B in Table 6.

Although the study was published in 1980, Wiens' efforts pre-dated the confirmation that current root and tuber crop data are valued at one-fifth natural weight in Chinese foodgrain statistics. His figures also implicitly include cassava, taro and minor roots and tubers. Adjustments for these

25. Thomas B. Wiens, "Agricultural statistics in the People's Republic of China," in Alexander Eckstein (ed.), Quantitative Measures of China's Economic Output (Ann Arbor: University of Michigan Press, 1980), pp. 44-107 and 275-326.




Table 6: Comparison of Official Foodgrain Production and Sown Area Estimates with Wiens' Recalculations of Official Data, and Wiens' Recalculations Adjusted for Consistent Root and Tuber Crop Inclusion, 1952-82

Sown Area Production (million hectares) (million metric tons)

Year A B C A B C

1952 123-979 126-3 125-9 163-915 167.0

163-1 1953 126-627 129-0 128-5 166-830 169-9 165-8 1954 128-995 130-2 129-7 169-515 171-1 167-0 1955 129-839 130-1 130-6 183-935 185-5 180-8 1956 136-339 133-4 132-8 192-745 187-1 182-0 1957 133-633 132-2 133-130 195-045 195-5 184-401

1979 119-263 119-263 332-115 332-115 1980 117-234 117-234 320-555 320-555 1981 114-958 114-958 325-020 325-020 1982 113-396 113-396 353-425 353-425

Notes: "Foodgrains" consist of rice, wheat, coarse grains, pulses, soybeans and root and tuber

crops. The A and B series, however, include estimates which value root and tuber crop production at one-fourth natural weight and include data for cassava, taro and other minor root and tuber crops, as well as sweet and white potatoes. The C series, consistent with current official Chinese definition, includes only sweet and white potatoes among root and tuber crops and values these among production data at one-fifth natural weight.

The A series consists of data as they appear among current official statistical publications. The B series are revisions of official data suggested by Thomas Wiens. They incorporate

official national yield data and revisions of cultivated area and cropping distributions. The cultivated area revisions correct the official totals for unregistered land which is assumed to have been in cultivation since 1949, but which was omitted from acreage statistics until 1954 or 1956. The cropping distributions are calculated from United States Central Intelligence Agency, "Agricultural acreage in Communist China, 1949-68: a statistical compilation," Washington, D.C., 1969 (which allows for adjustment for some under-reporting of minor crops among official data, but leaves the foodgrain sown area proportions of cultivated area identical to the official figures) except that data based on provincial foodgrain figures were substituted for the years 1955 and 1956. The discrepancies between national and provincial totals are considerable for these years (especially for 1956) and coincide with large officially claimed increases implied by the national data. Specifically, the provincial statistics for 1956 imply that the large increases in area sown with rice in that year were partially offset by declines in area sown with wheat and coarse grains, whereas the national figures suggest that the rice area increases came about without significant contraction of area sown with other crops. The yield figures used are official data (p. 58), because Wiens found no strong evidence to support the hypothesis of yield underestimation among the official national data in the 1952-57 period (pp. 57 and 297-306). The calculations were carried out to three decimal places, then rounded to the nearest 100,000 hectares and 100,000 tons, respectively.

Series C are recalculations (of Wiens' revisions) to exclude root and tuber crops other than sweet and white potatoes and to value the production data at one-fifth rather than one- fourth natural weight. Specifically, for 1952-56 Wiens' cropping percentages for root and tuber crops were deflated by the percentage of "other roots and tubers" among total roots and tubers (calculated from Table 3) and the total foodgrain percentages were revised accordingly. These were applied to Wiens' revised cultivated area figures to calculate total foodgrain sown area. The 1952-56 production data were calculated from Wiens' revised foodgrain production estimates by substituting new figures for root and tuber crop production. Wiens' revised root and tuber figures were deflated by the percentage of "other roots and tuber" production in total root and tuber output, then converted to one-fifth natural weight and substituted for Wiens' one-fourth natural weight figures (p. 63).




Wiens seems to have intended no revision of the 1957 statistics (see pp. 50, 58, 282, 295-96). The discrepancy with the official 1957 soybean-inclusive foodgrain sown area estimate lies predominantly with the difference between the official sown area estimate for soybeans and that implied by Wiens' cropping distribution percentage for soybeans. Wiens calculated the latter percentage using a soybean sown area figure of 11-333 million hectares from USCIA, Agricultural Acreage in Communist China, 1949-68. The official figure cited in Zhongguo Nongyebu, Jihuaju, Zhongguo yu shijie zhuyao guojia nongye shengchan tongji ziliao huibian, p. 32 and repeated in recent publications such as Zhongguo Guojia Tongjiju, Zhongguo tongji nianjian - 1983, p. 155 is 12-748 million hectares. An incomplete provincial compilation for 1957 based on the same CIA source totals,9-562 million hectares excluding seven provinces for which no 1957 data were available, among them major soybean producers such as Shandong and Hebei. The inclusion of proxy data from nearby years for the four most important missing provinces (again from the same CIA source) brings the compilation to 12-734 million hectares. Therefore, there appears to be no strong reason to reject the official data in favour of the CIA figure which may, in fact, be an error. Likewise, the discrepancy between the Wiens 1957 foodgrain production figure and the official figure is due to a transcription error, this time picked up from Nai-Ruenn Chen, Chinese Economic Statistics, p. 339 where foodgrain production (excluding soybeans) is misquoted from Zhongguo Tongjiju, Weida de shinian, p. 119, as 185-5 million tons rather than 185-0 million tons.

Therefore, the C series estimates for 1957 are not based on the Wiens 1957 data but on the official data. The figures for "other roots and tubers" are simply deducted from the official roots and tubers data. The remainder is then substituted for the official figures in the foodgrain data totals (after converting to one-fifth natural weight in the case of the production figure). Sources:

Series A are official data as they appear in current publications (from Table 4). Series B are calculated from data appearing in Thomas B. Wiens, "Agricultural statistics

in the People's Republic of China." The sown area figures are calculated from reconstructed official cultivated area figures (p. 282) and estimates of cropping percentages for foodgrains (including soybeans) for 1952-55 and 1957 (p. 288) and 1952 and 1955-57 (p. 296). The production figures are Wiens' revised estimates (p. 63).

Series C figures for 1952-56 are recalculations of the Wiens revisions and for 1957, direct recalculations of official figures, as explained in the notes. The 1979-82 figures are official data identical to those in Series A.

difficulties are reproduced as Series C. A comparison with the official data as they currently appear (Series A) demonstrates that the hypothesized computational errors among official data discussed by Wiens and the consistency problems treated here are largely cancelling for 1952-55, but not so for 1956 and 1957. The year 1957 is often used as the base year for growth rate calculations, so the difference of 10-644 million tons among the 1957 production statistics is particularly noteworthy. Since these 1957 data are derived directly from official data, they are not jeopardized by the somewhat conjectural nature of the Wiens revisions. The average annual long-term foodgrain production growth implied by the recalculations from 1957 to 1979, for example, is 2-71 per cent, as opposed to 2-45 per cent implied by the official data. The revised 1957 figures imply a 25-year average annual point growth rate in foodgrain yields of 3-30 per cent, compared with 3-08 per cent indicated by official data. The 26-year comparison using averages for the two periods gives 2-98 per cent per annum based on Series C and 2-87 per cent based on Series A.

The accounting shifts relative to definition and foodgrain equivalence become somewhat more important when shorter periods around the points of transition are examined or when the performance of root and tuber crops per se is scrutinized (Table 7). Among the implications of these



Table 7: Consistent Reconstructed Official Estimates of Production, Sown Area and Yields of Root and Tuber Crops under Current Chinese Definition (Sweet and White Potatoes Only), 1952-82

Production Sown Area (million metric tons of Yields

(million hectares) natural weight) (metric tons per hectare)

Year A B C A B C A B C

1952 8-688 8-2825 8-5 81-625 62-622 64-1 9-395 7-561 7-5 1953 9-016 8-5592 8-7 83-275 63-316 64-6 9-236 7-397 7.4 1954 9-781 9-2956 9-3 84-900 64-678 65-5 8-680 6-958 7-0 1955 10-054 9-6187 9-7 94-475 72-798 78-2 9-397 7-568 8-1 1956 10-992 10-4036 10-4 109-250 83-686 83-5 9-939 8-044 8-0 1957 10-495 9-9914 9-9914 109-600 83-780 83-780 10-443 8-385 8-385

1979 10-952 10-952 10-952 142-300 142-300 142-300 12-993 12-993 12-993 1980 10-153 10-153 10-153 143-625 143-625 143-625 14-146 14-146 14-146 1981 9-621 9-621 9-621 129-850 129-850 129-850 13-497 13-497 13-497 1982 9-363 9-363 9-363 133-400 133-400 133-400 14-248 14-248 14-248

Notes: The A Series are data as implied in current official publications. The B series adjust for the fact that the official "foodgrain equivalent" production for the 1950s

were actually computed at one-fourth natural weight and include,

cassava, taro, and other minor root and tuber crops. The C series reflects the hypothesis that Wiens' suggested revisions of official data were basically valid and recalculates his work for consistency as in Series B. Sources:

All 1979-82 figures and the Series A data for 1952-57 are converted to international units from Chinese unit data for "root and tuber crops" (actually including only sweet and white potatoes) found in Zhongguo Guojia Tongjiju, Zhongguo tongii nianjian - 1983, pp. 155 and 162. The original production figures, included at one-fifth natural weight, have been converted to natural weights. Yields have been calculated accordingly.

The Series B 1952-57 data are summed and converted to international units from disaggregated Chinese unit data for sweet potatoes and for white potatoes appearing in Zhongguo Nongyebu, Jihuaju, Zhongguo yu shijie zhuyao guojia nongye shengchan tongji ziliao huibian, pp. 26, 28, 29 and 31. The original production figures valued at one-fourth natural weight have been converted to natural weight. Yields have been calculated accordingly.

The Series C figures are recalculations (as described in the notes to Table 6) of revised official data appearing in Thomas B. Wiens, "Agricultural statistics in the People's Republic of China."

0\ 00

H

-D

C-




data are: (1) aggregate area sown with sweet and white potatoes in 1979 still exceeded any year in the 1952-57 period and the 1979-82 average was higher than that of 1954-57; (2) growth in average yields proceeded at more than 2-23 per cent per annum from 1952-57 through 1979-82 rather than 1-42 per cent implied by the official data; (3) the considerations raised by Wiens are not quantitatively important for examining aggregate sweet and white potato performance since 1952, with the minor exception of 1955.

Nlnce potatoes are grown in all provinces in China, the conversion to grain equivalence is germane to production data for all provinces. Table 8 presents long-term growth rates in root and tuber crop production adjusted for the shift. What remains to be done is to examine the quantitative implications of the change in crop inclusion.

The largest adjustment is due to the exclusion of cassava, but fortunate- ly it is confined to Guangdong and Guangxi since very little cassava is grown outside these provinces. The definitional shift is clearly more important for evaluating total foodgrain production and cultivation trends in Guangdong and Guangxi than it is for analysing national foodgrain data. But even here the impact of long-term rates, though measurable, is minor. For example, if Guangdong and Guangxi are lumped together to obviate the boundary change question, the average 25- year foodgrain production rate (1955-80, based on the 1953-57 and 1978-82 means) exceeds 2-1 per cent per annum (evaluating root and tuber crops at one-fifth natural weight, including soybeans throughout, but leaving cassava excluded from the latter data). If cassava production of 3 million tons (600,000 tons of grain equivalence according to the previous Chinese system) is added to the 1978-82 data, the long-term foodgrain production growth rate still does not reach 2-3 per cent per annum.

Tables 9, 10 and 11 explore the implications of the consistency problem for root and tuber crop data for these provinces. They reveal that root and tuber sown area has declined much less drastically than previously assumed in south China, while production has actually increased and yields have progressed at the respectable annual rate of 2-5 per cent (Table 11). The conclusions are strengthened by the fact that no reasonably accurate adjustment could be made to deal with the smaller inconsistencies presented by taro and other minor root and tuber crops included among the 1950s data but excluded from the most recent data appearing in these tables.

How important is the taro exclusion problem to a correct quantification of provincial data? If Buck's crop distribution estimate for 1929-3326 were roughly applicable to the 1950s, taro was probably more important in national statistics than cassava. But its field cultivation has certainly not expanded as has cassava's over the past three decades and total production has certainly been lower than that of cassava throughout the recent past. Furthermore, unlike cassava, it is suitable for planting in

26. See, supra fn 5.



Table 8: Long-term Growth in Root and Tuber Crop Production by Province, 1952-82

Production of Root and Tuber Crops See Average Footnote Annual

a Produc- tion

Growth Rate

1952-57 Province 1952 1953 1954 1955 1956 1957 1957 1952-57 1980 1979-82 1952-57 1957-80 /1979-80

(1,000 metric tons at ( (1,000 metric tons at 1 natural weight) natural weight) (%)

Estimates adjusted only for consistent foodgrain equivalence (I natural weight)) Heilongjiang 489 340 482 600 307 444 355 355 510 505 1-1 1-59

1.36 Jilin 265 163 170 136 159 200 220 0-7 1-69 1.26

Liaoning 210 354 310 390 312 253 105 106-25 1-0 -4-62 -3.28 Nei Mongol 413 330 282 273 326 278 222 254 300 371-25 1-7 1-32

1.47 Gansu 404T 323 323 440 362-5 2-0 1-35 0.445 Shaanxi 126t 101 101 685 605 0-5 4-25 7-13

Xinjiang 12 10 10 25 27-5 0.1 4-06 3.97

Qinghai 87 70 70 75 61-25 3-3 0-276 -0.512 Henan 1,653 1,742 2,047 1,794 2,292 1,735 1,388 1,502 3,525 2,933-75 3-2 4-14

2.61 Hebei 1,237 1,185 871 1,063 1,250 1,460 1,168 942 1,250 1,241-25 2-7 0-295 1.07 Shanxi 496 380 251 166 211 338 270 246 525 536-25 1-5 2-93 3.04

Shandong 2,390 2,386 2,967 2,965 3,751 3,500 2,800 2,394 5,555 5,082-5 4-6 3-02 2-94 Hunan 660 602 572 798 572 989 791 559 1,075 1,033-75 1-3 1-34

2.39 Hubei 460 425 340 457 740 445 356 382 875 955 1.0 3-99 3.59

Jiangxi 365 292 292 275 283-75 1-2 -0-26 -0.110 Anhui 1,816T 1,450 1,885T 1,615 1,292 1,354 2,125 2,017-5 3-4 2-19 1.55

Zhejiang 600 825 660 570 780 733-75 1.9 0-729 0.976

Jiangsu 517 414 414 1,190 1,373-75 0.9 4-70 4.72

o\

a

,-

?3



Guizhou 317 254 254 505 473-75 1-5 3-03 2.43 Sichuan 2,030 3,041 2,500 3,183 2,546 2,151 4,670 5,175 2-7 2-67 3.43 Yunnan 274 310 265 294 407 340 272 252 535 525 1.1 2-98 2.86 Fujian 709 651 888T 710 599 965 908-75 3-7 1-22 1.62 Guangxi 455 370 296 330 170 198-75 1-5 -2-38 - 193

Guangdong 1,266T 1,451 1,640 1,656 1,712 1,798 1,438 1,270 1,365 1,408-75 2-9 -0-226 0.40

(Adjusted estimates for provinces with new boundaries) Gansu 338T 270 270 440 362-5 2-0 1-93

1.14 Ningxia 50* 80* 64 52 65 48-75 2-0 0-067 -0'248 Hebei 992 950 699 852 1,003 1,171 937 756 1,250 1,241-25 2-7 1-26

1.92 Beijing 113 112 78 98 122 144 115 89 25 22-5 2-6 -6-42 - 515 Tianjin 168 161 119 148 181 211 169 132 25 23-75 2.7 -7-97

-6.38 Jiangsu 472 378 378 1,190 1,373-75 0-8 5-11 5-09 Shanghai 45 36 36 5 5 0-8 -8-22 - 731 Guangxi 577 572 458 460 170 198-75 1-7 -4-22 -

3.18 Guangdong 1,144 1,315 1,466 1,480 1,524 1,596 1,277 1,137 1,365 1,408-75 2-9 0-29 0-828

a: Estimated "reduction" in output due to shift from - to - natural weight. Notes:

The adjusted estimates attempting to account for boundary shifts are based on assumptions that root and tuber crops comprised consistent proportions of foodgrain output regardless of boundary changes. For some provinces this is rather distorting. See Tables 9, 10 and 11 for closer scrutiny of Guangdong and Guangxi.

The 1950s root and tuber crop data clearly include production of cassava, taro, and other minor roots and tubers, as well as sweet and white potatoes. The 1979-82 data include only sweet and white potatoes. No adjustments have been made in this table. The provincial estimated total for 1952-57 is 18-794, compared with the official national total of 18-771 million tons including "other roots and tubers." The 1952-57 official national total for sweet and white potatoes only would be 17-953 million tons (at one-fourth national weight). Around one-third of the difference is probably accounted for in Guangdong and Guangxi since "other roots and tubers" plus small amounts of white potatoes totalled 38% of the national difference for 1957. The remaining 1952-57 provincial production figures may consequently underestimate by an average of 3%. This implies slight under-estimations of the long-term yield growth rates for provinces other than Guangdong and Guangxi.

* Assumed. t 1931-37 average. t Circa.

Sources: From the left, columns 1-6, 8 and 11 are taken directly from Kenneth R. Walker, "China's grain production 1975-80 and 1952-57: some basic statistics," The China

Quarterly, No. 86 (June 1981), pp. 243-44. Columns 9 and 10 are based on data appearing in Luo Hanxian et al. (eds.), Zhongguo Nongyebu, Zhongguo nongye nianjian, 1981, pp. 26 and 27; Zhongguo Guojia Tongjiju, Zhongguo tongji nianjian - 1981, p. 147 and Zhongguo Guojia Tongjiju, Zhongguo tongji nianjian - 1983, p. 166. Columns 7, 11 and 12 were calculated accordingly. The material in the notes are based on data appearing in Tables 3-11.

?3 :rn

ct

0 C

C C H

C

-]

3

C

C ?




Table 9: Estimates of Root and Tuber Crop Production, Sown Areas and Average Yields in Guandgong and Guangxi, 1931-82

Production Sown Area Yields

Guangdong Guangxi Guangdong Guangxi (thousand metric tons Guangdong Guangxi (tons of natural

Year (of natural weight) (thousand hectares) weight per hectare)

1931-37 (1,972.65)* 636-35* (234-1)* 104-1" (8-43)* 6-11*

1949 4,880 (860) 723 6-75 1950 155 1951 794 1952 5,064 (1,820) 1953 5,804 913* 1954 6,560 777*/887 7-40 1955 6,580 1,003 6-56 1956 6,848 1957 6,257* (944* 1,242 (174* 5-79 (5-43*

/7,192 /1,480) /418) /3-54) 1958 7,860 1,333 5-90 1959 1,167 1976 288-68* 1977 1,108-55* 206-73* 5-36* 1979 (6,950)t 8751 (686-73)t 187-3$ (10-09)t 4-691 1980 (6,825)t 850$ (647)t 164-21 (10-54)t 5-181 1981 (6,800)t 900$ (615-8)t 175-71 (11-04)t 5-121 1982 (7,600)t 1,350$

Notes: Guangdong and Guangxi have traded counties several times over the past 50 years.

Recently Qinzhou Special District was transferred from Guangxi to Guangdong in 1955 and was transferred back to Guangxi in 1965. No attempt has been made in the table to adjust for these inconsistencies among various reported data. However, parentheses indicate that the enclosed figure excludes or is assumed to exclude Qinzhou.

Historically, root and tuber crops have consisted of sweet potatoes, cassava, white potatoes, yams, taro and possibly winter radishes and turnips. Suburban and perhaps some rural private plot plantings as vegetable crops may be excluded. Although all of these crops have been grown in Guangdong Province and Guangxi Zhuang Autonomous Region, root and tuber crop cultivation in these provinces in the 1950s consisted predominantly of sweet potatoes, taro and cassava. A delegation of Chinese statisticians visiting FAO at the end of 1979 indicated that their current concept of roots and tubers included only sweet and white potatoes, while cassava, taro and turnips were considered vegetables. This classification appears to be applicable to trade data. The 1976-77 provincial estimates of root and tuber production include sweet potatoes, white potatoes and taro but exclude cassava. Taro has probably been excluded since 1979 or so.

The 1931-37 yield data may be somewhat over-estimated while sown area data for 1931-37 and 1949-51 may be under-estimated.

* Refers to sweet potatoes only. t Probably excludes cassava, sown on around 200,000 hectares in 1980. Probably excludes

taro. I Probably excludes cassava sown on 168,331 hectares in 1976. Probably excludes taro.




Sources. All Roots and Tubers and Sweet Potatoes:

1931-37: National Agricultural Research Bureau data appearing in T. H. Shen, Agricultural Resources of China, pp. 375-77.

1949: Guangxi: Guangxi ribao, 25 February 1958. Guangdong: production data from Liang Rencai, Guangdong jingji dili, p. 19; sown area data from Sun Jingzhi (ed.), Huanan dichujingji dili in Joint Publications Research Service, No. 14954, 24 August 1962, p. 64.

1950: Guangxi: U.S. Central Intelligence Agency, "Agricultural acreage in Communist China, 1949-68: a statistical compilation."

1951: Guangdong: Liang Rencai, Guangdong jingji dili, p. 25. 1952: Guangxi: Guangxi ribao, 25 February 1958. Guangdong: Nanfang ribao,

24 September 1955 adjusted for boundary changes in Kenneth R. Walker, "China's grain production 1975-80 and 1952-57: some basic statistics," pp. 244 and 247.

1953: Guangdong: production data based on 1954 and Nanfang ribao, 5 October 1955 and roughly confirmed (6,000 tons) in Nanfang ribao,'7 April 1956, a reference which may include Qinzhou special district; sown area data from Nanfang ribao, 8 February 1956 and from Liang Rencai, Guangdongjingji dili, p. 19.

1954: Guangdong: production data from Nanfang ribao, 5 October 1955 and 7 April 1965; root and tuber sown area data from Nanfang ribao, 5 July 1955; sweet potato sown area data from Liang Rencai, Guangdong jingji dili.

1955: Guangdong: production figure from Nanfang ribao, 5 August 1956 assumed to be final figure including Qinzhou special district superseding 5,980,000 tons from Nanfang ribao, 5 October 1955 which may exclude Qinzhou; sown area data from Nanfang ribao, 5 July 1955.

1956: Guangdong: production data from Liangshi shengchan sudu keyi jiakuai (Grain Production Can be Speeded Up), cited in Walker's "China's grain production, 1975-80 and 1952-75," pp. 243-47, pp. 11-25, assumed to be final figure superseding 8,600,000 tons from Nanfang ribao, 5 August 1956.

1957: Guangxi: root and tuber production data from Guangxi ribao, 25 February 1958; sweet potato production calculated at 63-79% of root and tuber production as indicated in Sun Jingzhi, Huanan dichu jingji dili, JPRS, No. 14954, 24 August 1962, p. 257; root and tuber sown area data from ibid. p. 252; sweet potato yield data from ibid. p. 249; sweet potato sown area and root and tuber yield figures calculated from above information.

1957: Guangdong: root and tuber production data from Liangshi shengchan sudu keyi jiakuai, pp. 11-25; sweet potato production calculated at 87% of root and tuber production as indicated in Sun Jingzhi, Huanan dichujingii dili, JPRS; No. 14954, 24 August 1962, p. 68; sown area data from ibid. p. 64; yield figure calculated from above information.

1958: Guangdong: production data from Nanfang ribao, 1 October 1959; sown area data from Renmin ribao, 14 May 1958; yield figure calculated from above information.

1959: Guangdong: USCIA, Agricultural Acreage. 1976: Guangxi: area sown with sweet potatoes (hongshu) was 3-67% and with

foodgrains, 82-66% of total sown area (Guangxi Nongye Dili Bianxiezu, Guangxi nongye dili, p. 64). Total foodgrain sown area was 4,334,666 hectares (summed from data for constituent districts on p. 70).

1977: Guangxi: production and sown area data for sweet potatoes (hongshu) from Guangxi nongye dili, p. 68. Yield figure calculated from above information.

1979 and 1980: Luo Hanxian et al. (eds.), Zhongguo nongye nianjian, 1981, pp. 26-27. 1981: Zhongguo Nongyebu, Zhongguo nongye nianjian, 1982, p. 37; production data

also appears in Zhongguo Tongjiju, Zhongguo tong/i nianjian - 1981, p. 149. 1982: Zhongguo Tongjiju, Zhongguo tong/i nianjian - 1983, p. 166.

Cassava: Nongye tongji, p. 105 indicates that cassava is included among "other economic crops" and is no longer considered a "root and tuber crop" and hence, a "foodgrain." This information is consistent with the presentation of 1976-77 data in Guangxi nongye dili.

Guangdong: Cock and Kawano, "Cassava in China," pp. 1-2. Guangxi: Guangxi nongye dili indicates that area planted with cassava in 1976 was

2-14%, and foodgrains (excluding cassava), 82-66% of total sown area (p. 64). Total foodgrain sown area in 1976 was 4,334,666 hectares (summed from data for consistent districts on p. 70).

Taro: In Guangxi nongye dili, p. 76, taro is identified as a root and tuber crop (shulei). The book was published in 1980, but the data related to 1976 and 1977. A 1979 Chinese statistical delegation to FAO stipulated that taro was counted as a vegetable crop; only sweet and white potatoes are counted as shulei. Nongye tongji, p. 105, published in 1981 but containing data for 1979, gives the same information.




Table 10: "Consistent" Estimates of Roots and Tuber Crop Production, Sown Area and Yields in Guangdong and Guangxi, 1952-80

Production Yield

Guangdong Guangxi Sown Area Guangdong Guangxi (thousand metric (metric tons of tons of natural Guangdong Guangxi natural weight per

Year weight) (thousand hectares) hectare)

1952 4,576 2,308 1953 5,260 1954 5,864 1955 5,920 1956 6,096 1957 6,384 2,288 1,108 552 5-76 4-14 1976 457*t 1980 - 847t? -314t

Notes: 1950s data have been adjusted for consistency with current provincial boundaries. But

Guangdong (Guangxi) production figures may still over-estimate (under-estimate) by 150-250 thousand tons, and sown area figures, by around 45,000 hectares. Roots and tubers here include sweet potatoes, white potatoes, cassava and taro throughout, unless otherwise stated.

* This estimate may exclude small amounts of taro and white potatoes. t These estimates may exclude taro and very small amounts of roots and tubers other than

sweet potatoes, white potatoes, cassava and taro included in 1950s root and tuber data. Sources:

Production: Guangdong: 1952-57 figures are estimates adjusted for consistency with current

boundaries appearing in Walker, "China's grain production 1975-80 and 1952-57: some basic statistics," pp. 243-47. These estimates are based on: (a) 1952-57 foodgrain production data for Guangdong relevant to current provincial boundaries (given to Walker by Chinese officials in Guangzhou); and on (b) the assumption that the same share of roots and tubers in total foodgrain production for each year relevant to the 1955-65 boundaries, can be applied to the foodgrain production estimates relevant to the new boundaries in order to obtain estimates of 1952-57 root and tuber production relevant to the new boundaries. This is not, strictly speaking, correct. The boundary shift consisted, primarily, of transferring Qinzhou special district from Guangxi to Guangdong in 1955, then back to Guangxi in 1965. Qinzhou includes the entire current Guangxi coast, and extends north from the current provincial border to the Yu River, then angles south-west towards the border with Vietnam. In 1976, area sown with foodgrains in Qinzhou covered 461,333 hectares (Guangxi nongye dili, p. 70). The proportion of roots and tubers in total foodgrains on this tract was considerably higher than the average for Guangdong or for Guangxi either before or after the boundary change. Area planted with roots and tubers in the western district of Guangdong circa 1957 (including the Qinzhou special district and Zhanjiang prefecture) consisted of 28-3% of total area sown with foodgrains (excluding soybeans) as opposed to 18-6% in Guangdong province as a whole and 11-2% in Guangxi (Sun Jingzhi, Huanan dichu jingji dili in JPRS, No. 14954, 24 August 1962, pp. 64, 68, 179 and 252). Total sweet potato acreage in the district accounted for half the sweet potato acreage in Guangdong (Liang Rencai, Guangdong jingji dili, JPRS, No. DC/389, p. 79: probably based on 1954 and 1955 data). Since there is no precise way of correcting for the presumed higher proportions of root and tuber plantings in Qinzhou alone, no adjustments in this respect are made, but Walker's adjusted Guangdong estimates will still be biased upwards. The order of magnitude of the bias is probably 150-250 thousand metric tons.

Guangxi: These adjusted estimates are also from Walker, "China's grain production" and were derived by adding the difference of his estimates for "old" and "new" Guangdong to his estimates for "old" Guangxi for each year.




As discussed above, this procedure may result in under-estimates of "new" Guangxi root and tuber production of around 150-250 thousand tons.

Sown Area: Guangdong: For 1957, the share of roots and tubers in total foodgrain production

(including soybeans) for "old" Guangdong (Sun Jingzhi, Huanan dichujingji dili, JPRS, No. 14954, pp. 63 and 64) was applied to the 1957 foodgrain sown area figure for "new" Guangdong (written communication from Zhen Hua, vice-director, Agricultural Com- mission of Guangdong Province to Queen Elizabeth House, Oxford, China Study Group, June 1979 and cited in Peter Nolan, "Growth processes and distributional change in a south Chinese province: the case of Guangdong," p. 27). This renders an estimate consistent with Walker's production estimates. As a check, the proportion (excluding soybeans) of tuber area in Guangdong's western district (including Qinzhou and Zhanjiang) foodgrain area in 1957 (Sun Jingzhi, Huanan dichujingji, p. 179) was applied to the 1976 foodgrain sown area figure for Qinzhou special district (461,333 hectares found in Guangxi nongye dili, p. 70). The resulting estimate for 1957 root and tuber sown area was almost identical (1,111,000 hectares). For 1980, the root and tuber sown area figure from Luo Hanxian et al. (eds.), Zhongguo nongye nianjian, 1981, p. 26, was added to the cassava sown area estimated from Cock and Kawano, "Cassava in China," pp. 1-2.

Guangxi: For 1957, the difference between the estimates for "new" and "old" Guangdong was added to the 1957 figure from Sun Jingzhi, Huanan dichujingji, p. 252.

For 1976, total foodgrain sown area is summed from data for constituent districts (Guangxi nongye dili, p. 70) and percentages of area sown with foodgrain

(82.66%), sweet

potato (hongshu, 3-67%) and cassava (2-13%) are used to calculate the estimate. The "hongshu" percentage may exclude small amounts of taro and white potatoes.

For 1980, the root and tuber sown area figure from Zhongguo nongye nianjian, 1981, p. 27, is added to the difference of national and Guangdong cassava sown area estimates (Cock and Kawano, "Cassava in China," pp. 1-2).

Yields: These estimates are calculated from constituent sown area and production data.

Table 11: "Consistent" Estimates of Root and Tuber Crop Production, Sown Area and Yields in Guangdong and Guangxi Combined, 1952-80

Production Yields (thousand metric (metric tons of tons of natural Sown Area natural weight per

Year weight) (thousand hectares) hectare)

1952 6,884 1957 8,672 1,660 5-22 1980 10,675 1,161 9.19

Notes. Roots and tubers include sweet potatoes, white potatoes, cassava and taro. It is possible

that the 1980 data exclude taro and other minor tubers included among 1950s data, and incorporate increasingly under-estimated private plot cultivation of potato crops and cassava. Sources.

Production: For 1952 and 1957, data for Guangdong and Guangxi in Table 5 were summed. For 1980, data for the two provinces in Table 4 were summed and 3-0 million tons of cassava were added as cited in Cock and Kawano, "Cassava in China," p. 1.

Sown Area: Summed from estimates for Guangdong and Guangxi in Table 5. Yields: Calculated from production and sown area data.

many east, central and southern provinces. Figure 1 shows that Buck's students recorded taro cultivation in Guangdong, Guangxi, Yunnan, Jiangxi, Hunan, Fujian, Zhejiang, Jiangsu and to a lesser extent in Sichuan, Hubei, Henan and Anhui. This means that the impact of any




Figure 1: Per cent of Total Sown Area Planted with Taro, 1929-33.

-' .-

I-, (

P

- . -

AA ell -

C

**".'.".": ,'*":." ,

/ ..,

River,

,...... .

....

.-.":-...,.._•

,,++ +~ ~~,, .: , :,

" -0--Provincial Boundary

I ,j ,~ --,

"• "# ••" ie •

Proincia Bondr

Notes: In most of the localities growing taro, it seldom covers more than one 1% of the crop area. Little taro is grown outside the rice-tea, double cropping rice and southwestern rice areas.

Two varieties are grown, one on dry land and the other and most important on irrigated land, sometimes along the edge of rice fields. Some localities report considerable use for animal feed but on the average three-fifths is used on the farm as human food, and 28% is sold. (Taro is one of the main crops of the Yao tribes in northern Guangdong.) Source:

John Lossing Buck, Land Utilization in China (Atlas), p. 98.

minor distortion due to this inconsistency is divided among a large number of provinces and for most purposes will be negligible, with the possible exception of Guangdong. Likewise, inconsistencies relating to various minor roots and tubers other than cassava and taro are unlikely to present noticeable difficulties among provincial data since they are not apt to be highly concentrated and since cassava and taro no doubt make up the bulk of the "other roots and tubers" category.

Figure 2 indicates that the long-term yield performance of root and tuber crops throughout China has, until the last several years, matched that of the principal green revolution crops (rice, wheat and corn) while, in all likelihood, receiving far less favour in terms of capital construction investment (for example, in land improvement and current inputs such as




fertilizers, farm chemicals and machinery service).27 Figures 3 and 4 indicate the provincial location of root and tuber sown area and production in China, while Figure 5 demonstrates the tremendous differentials among average yields of root and tuber crops among Chinese provinces. Table 12 shows that mean yields for cassava in China (1979-81) are approximately equal to the world average. Mean yields for white potatoes are well below the world average, but not much below the average for Asia or for developing countries. Sweet potato yields in China (which dominate the statistics for "centrally planned economies"), however, surpass mean yields even among developed countries. Consequently, average root and tuber yields in the highest yielding localities (exemplified by Shanghai production) are comparable to the highest yields elsewhere. Mean yields in China's major high yield provinces are comparable with those of middle income European countries such as Norway (24-0 tons per hectare), East Germany (20-5 t/ha.), Italy (19-7 t/ha.), Poland (18-9 t/ha.), Greece (181 t/ha.), Czechoslovakia (17-9 t/ha.), Spain (161 t/ha.) and Portugal (9-6 t/ha.).28

Figure 6 shows long-term trends in production value among root and tuber crops in the world. Table 13, which gives a rough approximation of the long-term performance of China's three principal root and tuber crops, suggests that Chinese relative production trends of the three crops more or less mirror those occurring elsewhere, although cassava is the subordinate rather than dominate crop throughout. These trends, like the inter-provincial comparisons, cannot be considered definitive because of the inter-spatial and inter-temporal inconsistencies and ambiguities discussed throughout this article. But they provide a rough indication of comparative growth.

Area sown with sweet potatoes has declined as it has in many developing countries characterized by limited farmland and rising staple food production per capita. Yield growth, however, has proceeded at a very respectable long-term rate of more than 3 per cent per annum. This may be due to a complex of cropping shifts and agro-economic develop- ments, including retirement of some very marginal lands with low sweet potato yields, and increased application of current inputs and infra- structural investment on sweet potato land where the production focus has come to be not sweet potatoes, but an additional, more highly valued crop such as wheat, rice or corn. As might be expected, there is substantial sweet potato yield variation even within provinces. In Fujian, for example, high yield land averages 18-75 tons per hectare while low yield land

27. For the most part no chemical fertilizers are allocated for root and tuber crop production except on state farms. However, in several provinces such as Sichuan, some proportion of available chemical fertilizers are allocated on the basis of total sown area regardless of crop. But even in these cases, the fertilizer may not necessarily be applied to root and tuber crops. In fact, it is often said that potatoes produced with chemical fertilizers do not taste good. In general, if fertilizers are applied to root and tuber crops, they are more likely organic manures. However, the requirements in this regard are substantial. Research in Henan Province suggests that sweet potato yields in the range of 18-75-26-25 tons per hectare require 30-45 tons per hectare of manure. (Henansheng Nongyeting Henansheng Nonglin Kexueyuan, Hongshu, p. 74.)

28. FAO, 1981 FAO Production Yearbook.




Figure 2: Foodgrain Yields per Unit of Sown Area, 1949-82

14- Roots & Tubers (natural weight)

13-

12-

11

10

9

O7

6-

5 -Paddy Rice

4 - Roots & Tubers (1/4 natural wt.) / Milled Rice

•3 Maize

SWheat

1 - Soybeans

I I I I I I 1949 55 60 65 70 75 80




Notes: Roots and tubers in this figure include cassava, taro and other minor roots and tubers for

the 1950s but currently include only sweet and white potatoes. Cassava was already excluded by the mid 1970s but taro seems to be included until around 1979. Since the exact quantities and the most appropriate transition dates are unknown, no adjustments have been made, but Chinese cassava production is only about 2% of the national total for aggregated root and tuber crops. Taro production is certainly much less and that of other minor roots and tubers less still. Since average yields of these minor root crops are less than the average for sweet and white potatoes, the apparent increase in yields will be overstated but only very slightly. Data presented in Food and Agriculture Organization of the United Nations, Agricultural Commodity Projections, 1970-80, Vol. II (Rome: FAO, 1971), Table 15 suggests that the caloric contents of wheat, maize, soybeans and milled rice are roughly equivalent per unit weight. White potatoes have around 20% of an equivalent caloric content per unit weight; sweet potatoes have around 27%; cassava

30.3%; and taro around 22%. Given China's

distribution of production among these crops, dividing aggregate production of root and tuber crops by four may be the best common approximation of grain equivalence if the focus of comparison is caloric content. 1949-56 yields have been adjusted for biases in statistical generation procedures (e.g. see Table 7, series C). Sources.

The 1957-81 sown area data used in calculating yields in this figure appear in Zhongguo Tongjiju, Zhongguo tongii nianjian-1981, p. 139. The 1957, 1962, 1965 and 1978-81 production data appear on p. 143. The data are from Zhongguo Tongjiju, Zhongguo tong/i zhaiyao 1983, pp. 24 and 25. Remaining post-1957 production data for wheat and rice are from He Gang et al. (eds.), Zhongguo nongye nianjian, 1980, p. 34. Other basic 1950s data for maize, soybeans and roots and tubers are from Zhongguo Nongyebu, Zhongguo yu shijie zhuyao guojia nongye shengchan tongii ziliao huibian and Zhongguo Tongjiju, Weidade shinian. The 1976 and 1977 production data for maize, soybeans and roots and tubers are Ministry of Agriculture data given to international delegations. The 1957-82 sown area data and 1957, 1962, 1965 and 1978-82 production data are consistent with those found in Zhongguo Tongjiju, Zhongguo tong/i nianjian - 1983, p. 155 and 158. Virtually all 1957-82 sown area and output data required for producing this table may be found in the latter source. The 1949 and 1952-56 data are recalculations of official data to correct for biases in statistical generation procedures. The recalculations are only very significant for 1949-51.

averages 3-0 tons.29 According to surveys of 16,786 farms conducted under the direction of John Lossing Buck from 1929 to 1933, already 7 per cent of sweet potato production within surveyed localities was fed to livestock, 18 per cent among the south Chinese farms."3 Today, the proportion fed to livestock is almost certainly much greater, but many areas rely on the sweet potato as a staple food crop and as food security storage. Although sweet potatoes constitute about one-eighth of Fujian foodgrain production, they comprise 60-70 per cent of production in around one-fifth of Fujian's counties and municipal areas. The figure is as much as 90 per cent in some counties.31

White potato yields have increased at a more modest 1.8 per cent per year, but acreage has expanded dramatically and white potatoes may now rival sweet potatoes as the most extensively planted root or tuber crop if we may assume that the considerable reduction in root and tuber acreage 1978-82 reflected a fall in cropping intensity, eliminating sweet potatoes (notably in Sichuan, for example), as well as less extensive retirement of marginal lands (affecting both sweet and white potatoes). One would suppose that the increase in white potato acreage primarily reflects expansion of production onto previously uncultivated mountainous and

29. Fujiansheng Nongyeting, Ganshu, p. 4. 30. John Lossing Buck, Land Utilization in China, Atlas, p. 82. 31. Fujiansheng Nongyeting, Ganshu.




00

I

O

@

a

Millions of Hectares o .o .o o

" Heilongjiang 81 80/79

< 1.0'81 180/79 1.0

Liaoning '81/'79 1.40

O Jilin 79-'81 Z 1.0

Shandong 81 '80 79 1.71

Hebei 1.55'81 '80/79

Beijing '79-'81 S 1.69

O Tianjin '79-81 Z 1.54 Henan

'81 '80 '79 1.65

Shanxi 81 79 1.12

Shaanxi '81 '80/'79 1.39

Gansu '79-'81

H- 1.06

w Nei Monggol '81 79 1.0

Ningxia '81/79 S 1.08

0 Z Xinjiang '79-81 1.10

Qinghai '79-'81 1.0

Zhejiang '79 '81 2.27

Jiangsu '80 '81/'79 V 2.03

Shanghai 79-'81 2.43 1 Anhui '80 '81 '79

1.73

Hubei '81 '80/'79 S 1.89

Hunan

.Hun

'81 '80/ 79 Z 1.95

S Jiangxi '80 '79 1.85

Guangdong '81 '80/ 79

Guangxi '80 79 1.97

_

0 7 Fujian 79

'80 2.01 11 Sichuan '80 '811 79 1.90

SGuizhou 81 80/79

S1.55 Yunnan

1.48 '79-'81

V Xizang 1.0

National I --]

9.62 9.89 1.54 ('79)




Note: The number that accompanies the name of each province denotes the multiple cropping

index for foodgrains for that province. Where statistics for a particular province differ very little among the subject years, only the highest and lowest years or the 1979-82 average were recorded on the figure. Sources:

The data upon which the figures are based are from Luo Hanxian et al. (eds.), Zhongguo nongye nianjian, 1981, pp. 26-27; Zhongguo Nongyebu, Zhongguo nongye nianjian, 1982, p. 37; and from Zhongguo Tongjiju, Zhongguo tongji nianjian - 1983, p. 166.

other poor lands throughout China, as well as the potato's particular importance in China's principal reclamation areas in Heilongjiang and Inner Mongolia, accounting for around 100,000 hectares. Seen in this light, the modest improvement in aggregate yields appears more impressive.

Cassava, while a poor third in national importance, has probably tripled or quadrupled in both production and area in the two southern provinces where it is grown. The highest yields are comparable to the highest yields anywhere in the world,32 but aggregate yield performance is less clear. It is certainly evident and not surprising, however, that area has declined in the fertile Pearl River Delta33 and that there has been considerable expansion onto virgin lands in Guangxi and on Hainan Island, as well as impressive yield growth in a few areas such as the Zhanjiang prefecture of Guangdong. Furthermore, considerable quantities of cassava are grown on private plots, on narrow strips adjacent to roads and fields, and on tiny corners of land which may not be counted even among private plot statistics. There is also some illegal cultivation: under trees on state rubber plantations, for example.34

The question of whether all plantings of a particular crop are included in statistics, for which inclusion is specifically required, is a general problem throughout China and for all crops, which will not be addressed here. But it should be noted that this problem is particularly relevant to root and tuber crops, which are often planted on remote hillsides or sparsely and intermittently planted on other marginal lands not normally considered fields. One clear example is potato production in Tibet, which is non-existent according to official data, although transhumant hillside cultivation of potatoes is important throughout the Himalayas for the subsistence and food security of mountain peoples. It is quite possible that

32. Cock, James, director, Cassava Program, International Center for Tropical Agricul- ture, conversation, Palmira, Colombia, April 1983; and correspondence, 24 June 1983.

33. Cassava cultivation in Dongguan county declined from 47,361 mu in 1978 to 42,252 mu in 1982. In Fucheng commune within the county, area sown with cassava fell from 7,500 mu in 1980 to 5,506 mu in 1981, but recovered to 6,515 mu in 1982. On the other side of the Delta, in Taishan county, large-scale cassava cultivation began after 1979 along with a concerted expansion of pig-raising. Average yields throughout Dongguan county have increased from 11-7 tons per hectare in 1978 to 15-8 tons in 1982, reflecting more than weather differences. In the Delta, cassava is sometimes processed to a powder and mixed with other fodder items, most notably corn imported from the United States. The above data were given to Graham Johnson during visits of Guangdong in December 1981 and summer 1983 (Graham Johnson, Department of Anthropology and Sociology, University of British Columbia, correspondence, 19 September 1983); Cock and Kawano, "Cassava in China."

34. Cock and Kawano, "Cassava in China;" James Cock, conversation and correspondence.




el

u

00

0

0\

0O

ON d

1.

1.

O O

C4

Millions of Metric Tons

H Heilongjiang '82 79 1.0

Liaoning '79-'82 1.40

0 Jilin '79-'82 Z 1.0

Shandong '81 '82 '79 '80 1.71 Hebei 81 '82 1.55

Beijing 79 82 1.69

0 Tianjin '79-'82 Z 1.54

Henan '82 '81 79 '80

Shanxi '81 82 1.12

Shaanxi ' 81 79 1.39

Gansu '2 '80 1.06 82 80

S NeiMonggol 01182

Ningxia '79-'82

Z Xinjiang '79-'82 1.10

Qinghai '79-'82 1.0

Zhejiang '791 '82 2.5274

Jiangsu '80 81

S Shanghai 79-'82 2.43

Anhui '79 81 1.73

Hubei '80 82

1.89

Hunan81 79

Jiangxi 7982 1.85 '79-'82

Guangdong '81 82 2.26

Guangxi /2 Fujian '79 80

Sichuan '80 82 11'81 _79 1.90

w Guizhou P81 82

1.55 Yunnan '79 '1.48

79 '82 O

Xizang 1.0

National 25.97 26.68 27.84 28.41 1.54 ('81) ('82) ('80) ('79)





index for foodgrains for that province, Where statistics for a particular province differ very little among the subject years, only the highest and lowest years or the 1979-82 average were recorded on the figure. Sources:


potatoes are included with vegetables or with "other miscellaneous grains" in Tibet. But it is even more probable that transhumant Himalayan cultivation is very incompletely captured in official data. This type of difficulty is most relevant to cassava since a very large proportion of total cassava cultivation is heterogeneously scattered as indicated above, and because it is often cultivated on virgin lands under trans- formation, prior to their registration as farmlands.

Most Chinese cassava is grown for swine feed (and perhaps food security storage). But in some poor areas it is the principal human calorie source, so it is not impossible that in such areas, cassava is still counted as shulei and a "foodgrain." Cassava's minor role as an industrial starch may have peaked in the 1960s. Tapioca (an extract of cassava) has some minor importance in even urban cuisine, on specific festival occasions, and, like taro, may be significant among certain south Chinese minorities. But consumption in these respects has expanded slowly if at all. Cassava noodles have also been introduced, and cassava is also used for glucose extraction and to produce brewers' yeast and wine.35 But by far the principal use of increased production has been as swine feed, and, more recently, for export as dried cassava to Europe.

In 1962 the European Economic Community (EEC) enacted the Common Agricultural Policy, placing high import tariffs on corn and barley to protect EEC feedgrain producers. Imports of dried cassava, however, have been protected by an EEC regulation since 1975 limiting the duty to 18 per cent of the barley tariff. In addition, the General Agreement on Tariffs and Trade established a tariff ceiling for dried cassava at 6 per cent of market value.36 These enactments, coupled with high domestic feedgrain prices fostered by the prohibitive corn and barley tariff, made international shipment of cassava pellets to Europe a lucrative venture. Thailand was quick to take advantage of the opportunity, establishing early and increasing dominance of the market, with Indonesia and Brazil following at a considerable distance. From 1974 to 1978, China's exports of dried cassava to Europe averaged a miniscule 3,400 tons compared with Thailand's peak year of 5-9 million tons in 1978.37 In

35. Cock and Kawano, "Cassava in China," p. 1; Graham Johnson, correspondence, 19 September 1983.

36. Prasarn Trairatvorakul, "Food demand and the structure of the Thai food system," Ph.D. dissertation, Harvard University, Graduate School of Business Administration, 1981, pp. 229-31.

37. European Community, Analytic Tables of Foreign Trade, Vol. A (Luxembourg: Statistical Office of the European Communities, various years) compiled in Ulrich Koester, Policy Options for the Grain Economy of the European Community: Implications for Developing Countries, Research Report No. 35 (Washington, D.C.: IFPRI, 1982), p. 34.




00

roo

09

00

I

O

O

tr•

[..

g=

O

O

+ii

bo Ct

(Tons per Hectare)

I I

I I

I I I

Heilongjiang '81 '80/'79 1.0

Liaoning '79 '81/80 1.40

0 Jilin '80 '79/'81 Z 1.0t

Shandong '81 '79 '80 1.71 Hebei '79 '81/'80 1.55

SBeijing '81 '80/79 1.69

0 Tianjin '79 '81 '80 Z 1.54

Henan '79 '81/'80 1.65

Shanxi '81 '79/'80 1.12

Shaanxi '81 '79/80

Gansu '81 '79/80 - 1.06

inghai '81 1 79/80 1.08

S Xinjiang

'8181 880 0/779

1.1079 80 81 Shainghai 81

'79/'880 1.0

2.27

Jiangsu '797880/ 81 2.03 G Shanghai '80

2.43

Anhui '79 '80 '81 1.73

Hubei '79-80 81 1.89

HunXizang80

HPnan81 '79-'80 Z 1.95 U Jiangxi '79 '81/'80 1.85

Guangdong '79 '80/'81 2.26

- Guangxi '79 '81/80 :D 1.97

C Fujian '79 '80/'81 2.01

Sichuan '80-'81 '79 1.90

Yunnan '79 '80/81 :D 1.48 0 (1 Xizang '81

1.0

National '79 '81/180 1.54





index for foodgrains for that province. Where statistics for a particular province differ very little among the subject years, only the highest and lowest years or the 1979-82 average were recorded on the figure. Sources:


1979, however, at the request of France and Italy and over the objections of Holland and other European meat producers using Thai cassava, the EEC Council of Ministers began to pressure Thailand into a "voluntary" quota agreement. The annual Thai quota has been lowered in subsequent negotiations to 5 million tons in 1983 and 1984 and 4-5 million tons in 1985 and 1986, with an additional 0-5 million tons exportable across each

pair of years at the discretion of the Thais.38 Whether a direct result of the quota limitations on Thailand, of a sharp

increase in the Thai farm-gate price in 1979-80,39 or owing to general Chinese awakening to the opportunity, China's dried cassava exports rose from 1,000 tons in 1978 to 51,000 tons in 1979 and 336,000 tons in 1980.40 Exports for 1981 were no doubt higher still. A 27 per cent increase in European imports of cassava was attributed (though surely not exclusively) to China41 and in 1982 the EEC Council of Ministers entertained a

request that the 370,000 ton quota applicable to China as a non-GATT member be raised by 100,000 tons.42 When converted to fresh root

equivalent, 1980 exports approached one-third of domestic cassava production and 1981 and 1982 shipments undoubtedly exceeded that proportion.43

Summary and Conclusions

This analysis of PRC root and tuber crop data has led to some interesting conclusions, several of which may not be readily discernible

38. Hugh Corbet, "Excesses of the CAP and Thailand's manioc," The World Economy, September 1982, pp. 208-210; Ammar Siamwalla, "More aspects of the manioc agreement between Brussels and Bangkok," The World Economy, March 1983, pp. 89-90. H. Grote, "Miissen Tierhalter ffir Fehlentwicklungen biissen?" "Must animal breeders suffer from misguided farm policies," DLG Mitteilungen (German Agricultural Association Reports), July 1983, pp. 415-19.

39. The Thai farm-gate price for cassava more than doubled in 1979 and 1980 compared with the 1978 level. See Thailand, Ministry of Agriculture and Cooperatives, Selected Economic Indicators Relating to Agriculture (Bangkok: MAC), p. 58 and Thailand, MAC, Agricultural Statistics of Thailand, Crop Year 1980/81 (Bangkok: MAC, 1981), p. 24. This would have placed the Thai farm-gate price above the Chinese compulsory procurement price for cassava.

40. Koester, Policy Options. 41. "Manioc imports into E.C. up 27 per cent in year; more by China," Milling and

Baking News, 8 December 1981. 42. Reuter International News Services cited in "EC may raise China manioc quota,"

Hong Kong Standard, 26 October 1982. 43. The extraction rate for dried cassava is typically around 40% of fresh root weight.

Pelletized cassava may be 89% of dried weight (Trairatvorakul, "Food demand and the Thai food system").




Table 12: Average Yield of Root and Tuber Crops in China and Elsewhere, 1979-81 Average

White Sweet All Roots Cassava Potatoes Potatoes and Tubers*

(metric tons of natural weight per hectare)

High Yield Chinese Provinces

Shanghai 45-9 (0-02) Zhejiang 26-0 (2-4) Shandong 19-8 (18-7) Fujian 18-9 (3-3) Jiangsu 18-1 (4-8) Tianjin 14-3 (0-1) Hunan 14-0 (3-8) Henan 141 (11-6) Sichuan 13-8 (19-0) Anhui 13-4 (7-4)

Total (71-4)

Centrally Planned 7-8 11.9 16-6 12-9 Economies

China 8-6t 9-4T 18-7? 14-0 Other Asian 7-3 10-4 6-1 7-4

European (including - 131 - 13-1

U.S.S.R.) Market Economies 8-8 17-6 7-6 10-4

Developing 8-8 10.9 7-1 8-5

Developed - 24-0 15-4 23-6

World 8-7 13.4 14-0 11-6

Notes: Parentheses indicate the provincial share of national production. * Although Chinese official practice now seems to exclude cassava from root and tuber

crops, cassava is included among "all roots and tubers" in this table, conforming with FAO practice. Taro is currently included in neither FAO nor Chinese classification of "roots and tubers."

t This is a 1980 figure. $ This is a 1978 figure. ? This "1980" figure was derived as a residual using 1980 data for total roots and tubers

(excluding cassava) and deducting the 1978 white potato data. It therefore includes very minor amounts of taro and implicitly assumes that the decline in root and tuber sown area between 1978 and 1980 reflected declines in area sown with sweet potato (and taro) only. The corresponding residual using 1978 total root and tuber data and deducting 1978 white potato data would imply a 1978 sweet potato (plus taro) average yield of 16-4 tons per hectare.

Sources: The Chinese provincial data were calculated from sown area and production data for 1979

and 1980 from Luo Hanxian et al. (eds.), Zhongguo Nongyebu, Zhongguo nongye nianjian, 1981, pp. 26-27; and from Zhongguo Nongyebu, Zhongguo nongye nianjian, 1982, p. 37.

The national data for China are based on material cited in Table 3 and Table 8. See notes

t, +, and ? for details. The other data are found in or are based on material found in Food and Agriculture

Organization of the United Nations, 1981 FAO Production Yearbook (Rome: FAO, 1982), pp. 109-117, although China data from this paper were substituted for the FAO figures. The Chinese figures used in the recalculation are the same as those appearing in Tables 2 and 7




(the 1980 figures for cassava, the 1978 figures for white potatoes, the 1979-81 figures for total roots and tubers), except that the sweet potato figures were estimated by averaging the differences between the 1978 white potato figures and the 1979-81 total root and tuber figures.

Figure 6: Trends in Value of Root and Tuber Crop Production in All Developing Market Economies, 1948-80

109 US$ 10

8Cassava

Sweet Potatoes

White Potatoes

1950 55 60 65 70 75 80 Years

Source: Doug Horton, John Lynam and Henk Knipscheer, "Root and tuber crops in developing

countries: an economic appraisal," a paper presented at the Sixth Symposium of the International Society for Tropical Root Crops, held in Lima, Peru, 20-25 February 1983.

from aggregate statistical collections or previous studies. Some assist our understanding of the Chinese statistical system and the consistency of its products. A few of the principal points may be worth reviewing.

1. Root and tuber crop yields in China have increased at an average annual rate of more than 2-2 per cent since 1952, comparing favourably with green revolution crops such as rice, wheat and maize until the last several years. Yield growth of each of these crops has accelerated since the late 1960s.

2. On the basis of produced caloric content per unit of sown area, average root and tuber yields have remained superior to those of all other grain crops in China throughout the People's Republic period.

3. There is considerable average root and tuber yield variation among provinces in China. Yields typical of most field production in Shanghai and Zheijiang (and no doubt mirrored in the most advanced areas of several provinces) rank with those of the most advanced developed countries. Average yields in even a major root and tuber producing province like Shandong (19 per cent of national production) are comparable with those of middle income European countries. On the other hand,




Table 13: Comparative Development of PRC Sweet Potato, White Potato and Cassava Production, 1957-78

Sown Area Production Yields

Sweet White Sweet White Sweet White Potato Potato Cassava Potato Potato Cassava Potato Potato Cassava

(million metric tons, Year (million hectares) natural weight) (tons per hectare)

1957 7-93 2-06 70-28 13-50 <1-01 8-86 6-55 1978 -6-8* -5-0 0-35t ~111-7 -47-0 3-Ot -16-4* 9-4 8-6t

Notes: * These estimates were derived by deducting white potato estimates from total root and

tuber data and may include small amounts of taro (perhaps around one million tons on approximately 100,000 hectares), depending upon the exact date that taro ceased to be included among total root and tuber data. Taro was clearly included among 1976 root and tuber crop data for Guangxi, but it was clearly excluded on an official national basis by 1981 and probably by 1979.

t These are probably 1980-1981 figures, and may under-estimate the considerable areas and amounts of cassava grown on private plots. A Chinese source published in 1980 estimated that cassava was recently grown on 7 to 8 million mu, 470-530 thousand hectares.

$ Roots and tubers other than sweet and white potatoes totalled 3,896,000 tons and covered 503,300 hectares nationally in 1957. But cassava is grown almost exclusively in Guangdong and Guangxi, where roots and tubers other than sweet potatoes totalled 1,471 million tons in 1957. At least taro and small amounts of white potatoes and other minor roots and tubers are included in this figure, as well as cassava. Total cassava production was therefore less than one million tons in 1957. Sources:

1957: Sweet potato, white potato and total root and tuber data are from Zhongguo yu shijie zhuyao guojia nongye shengchan ziliao huibian, pp. 25-31. Roots and tubers other than sweet potatoes totalled 935,000 tons in Guangdong and 536,000 tons in Guangxi, including cassava, taro, small amounts of white potatoes and other tubers such as mao potatoes (Table 4).

1978: A Chinese broadcast translated in FBIS, 10 September 1979, p. T4 indicated that

potato sown area rose from 20 million mu in 1949 to 80 million mu while yields increased from 700 to 1,300 jin per mu. Xinhua, news bulletin, 19 September 1979, p. 5, reported that

potatoes covered 4-6 million hectares and yielded 9 tons per hectare. These reports covered the same conference and are assumed to be different roundings of the same basic data for 1978 (between 70 and 80 million mu, with yields between 1,200 and 1,300 jin per mu). The

mid-points of these ranges were taken. Current white potato plantings on around 5 million hectares are continual in Chinese communications to Richard Sawyer, director-general, International Potato Center, Lima, Peru (circa 1981-83).

The sweet potato figures (including taro) were derived by subtracting the white potato estimates from total root and tuber data found in Zhongguo Tongjiju, Zhongguo tong/i nianjian - 1981, pp. 139 and 143.

The cassava data are from Cock and Kawano, "Cassava in China," p. 1, and may be for 1980. The sown area data are roughly confirmed by a Guangdong figure of 200,000 hectares in ibid. pp. 1-2, and a Guangxi figure for 1976 of 168,331 hectares calculated from Guangxi Nongye Dili Bianxiezu, Guangxi nongye dili, pp. 64 and 70. However, Zhongguo Kexueyuan, Dili Yanjiusuo, Zhongguo nongye dili zonglun, p. 129 states that cassava has been sown on 7-8 million mu "in recent years," probably referring to somewhere in the 1971-78 period.

The notes on taro are based on Guangxi nongye dili, p. 76 and Nongye tong/i, p. 105.




average yields in Ningxia, Guangxi and other low-yield provinces are

comparable with those of the lowest yielding countries of the world. 4. Relative production trends among root and tuber crops in China are

not dissimilar to those found in the rest of the developing world. Sweet

potato area is declining while plantings of white potatoes and cassava are

rapidly increasing. Of course this pattern is generally the result of complex cropping shifts rather than direct substitution among root and tuber

crops. 5. The most striking feature of root and tuber crop development in

China (by far the world's leading producer of sweet potatoes) is the long- term growth in sweet potato yields of over 3 per cent per annum, leading to average yields that are high even by developed country standards. Achievement of such yields would be very unlikely without considerable fertilizer application, although much of the fertilizer applied appears to be

organic. 6. Another striking feature is the very rapid expansion of white potato

plantings coupled with more modest yield growth, leading to a long-term production growth rate of more than 6 per cent per annum. Mean yields, however, are still below the average for developing countries.

7. Another interesting feature of Chinese root and tuber crop development is the recent explosion of south Chinese cassava exports to the

European Economic Community and the more active development of cassava as a swine feed, even reversing the long-term decline in cassava

plantings in various areas of the Pearl River Delta. As elsewhere, the

expansion of cassava plantings onto virgin and marginal lands in the two

producing provinces (Guangxi and Guanigdong) has brought about considerable long-term growth. Yields are only average by world standards although the highest yields are comparable to the highest yields elsewhere.

8. According to Chinese statistical convention root and tuber crops included cassava and taro in the 1950s, but excluded cassava by the mid 1970s. Mid 1970s root and tuber crop data seem to include taro, but 1981 data (probably even 1979 data) do not. Current statistical convention dictates inclusion of only sweet and white potatoes. Cassava, taro and other minor root and tuber crops now excluded from shulei statistics accounted for 4-5 per cent of sown area and production of all roots and tubers in the 1950s. Officially, "root and tuber crops" were valued at one- fourth natural weight through 1963 (when presented in conjunction with

"foodgrain" data), but one-fifth thereafter, although local variation may persist. Whether or not cassava is included, one-fourth natural weight is a closer common factor than is one-fifth for application to aggregated root and tuber crop data for China, in order roughly to approximate the caloric equivalence of grain. Cassava is currently treated as a vegetable among Chinese international trade statistics, but as an economic crop among production data. Taro, like turnip and winter radish, is currently classified as a "vegetable" among production and trade data, alike.

9. In order to make a rough adjustment to include cassava among "root and tuber crops" throughout the PRC period, roughly

3.0 million




tons (natural weight) and 350-500 thousand hectares must be added to data for Guangdong and Guangxi for recent years. The impact on "foodgrain" data trends is trivial nationally, and consistent inclusion of cassava does not even raise the 25-year foodgrain growth rate in Guangdong and Guangxi by 0-2 per cent per annum. But allowing for the shift is more important when examining the performance of root and tuber crops. This is especially true for the two southern provinces: (a) root and tuber crop acreage has declined much less drastically than previously assumed; (b) root and tuber production has increased, not decreased since the 1950s; (c) yields have progressed respectably at more than 2-5 per cent per annum.

10. Corrections for the hypothesized computational errors inherent in the 1950s official figures discussed by Wiens are more or less offset among foodgrain data for 1952-55 by corrections for consistency with current statistical conventions. But the corrections are not offsetting for the 1956 and 1957 data. The consistency issues are of some quantitative importance for aggregate 1950s root and tuber crop data, but also allowing for the computational issues discussed by Wiens has little offsetting quantitative impact on root and tuber crop data, with the minor exception of production and yield data for 1955.



an analysis of chinese data on root and tuber crop production

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