The present paper deals especially with the cropping systems in upland fields where tobacco is not cultivated; the characteristics of which run as follows:
(A) Summer Crops. (1) In each section the repetition of same crops is avoided as a rule, although crop-alternation are generally irreguler. (2) Though the kind of summer crops are same in each section, the dominant crops in acreage, which appear most frequently in the present cropping systems, are upland rice and barnyard millet in the upland field section α, and upland rice in β. No predominance would take place by such crop as upland rice or barnyard millet in the paddy field section.
(B) Winter Crops. (1) In every section wheat acreage reaches approximately as much as two times that of barley, often resulting with the repetition. of the former, in the present systems. (2) Regarding the ratio between barley and wheat appearing in the systems, every section has a different value The contrast of the ratio is most striking between the paddy field section and that of upland field as a whole. This areal difference arises from the, characteristic combination of rice and tobacco with barley as preceding crop, because of the reason worked out in the foregoing paper. Although wheat plays dominant part as winterr crop throughout both the upland field and paddy field sections, barley replaces it rather frequently in the former. Concerning the latter section on the other hand, wheat is nearly an exclusive winter crop cultivated in. the present systems.
The following are examples, where a, b and c signifie the upland field. sections α, β and paddy field section respectively.
(a) Weat-corn-rape-barnyard millet-barley-german millet-wheat-land rice……
(b) Barley-vegetables-wheat-buckwheat-barley -upland rice-wheat-sweet potato……
(c) Wean-upland rice-wheat-soybeann-wheat-satoimo (taro)-wheat-corn……
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