Paddy adjustment has clearly shown that paddies above the average size are more economically worked than small ones, but these adjusted paddies are on the plains and a large proportion of Japanese paddies have had to be made on uneven or hilly ground where physical conditions make it impossible for these rice fields to be anything else than small and irregular. Japanese agriculture is what it is and must largely remain what it is because Japan is geologically and climatically what it is, and because the social development of a large part of Japan is what it is. Comparisons with rice culture in Texas, California and Italy are usually made in forgetfulness of the fact that the rice fields there are generally on level fertile areas, in America sometimes on virgin soil. In Japan rice culture extends to poor unfavourable land because the people want to have rice everywhere.[290] The Japanese have cultivated the same paddies for centuries, Some American rice land is thrown out of cultivation after a few years. In fertile localities the Japanese get twice the average crop. It must also be remembered that Japanese paddies often produce two crops, a crop of rice and an after-crop. Japanese technicians are well acquainted with Texan, Californian and Italian rice culture, and Japanese have tried rice production both in California and Texas. "They talk of Texan and Italian rice culture," said one man who had been abroad on a mission of agricultural investigation, "but I found the comparative cost of rice production greater in Texas than in Japan. Some Japanese farmers who went to Texas were overcome by weeds because of dear labour. In Italian paddies, also, I saw many more weeds than in ours. It is rational, of course, for Americans and Italians to use improved machinery, for they have expensive labour conditions, but we have cheap labour. The Texans have large paddies because their land is cheap, but ours is dear. In these big paddies the water cannot be kept at two or three inches, as with us. It is necessarily five inches or so, too deep, and the soil temperature falls and they lose on the crops what they gain by the use of machinery. Further, it must be remembered that we are not producing our rice for export. It is a special kind for ourselves, which we like;[291] but foreigners would just as soon have any other sort. We have no call, therefore, to develop our rice culture in the same degree as our sericulture, which rests mainly on a valuable oversea trade."