In this paper, the writer dealt with lotus root growing at the Tamura and Okijuku districts in Tsuchiura city which are located in the western shore of Lake Kasumigaura. He made clear the relationship between land conditions and lotus root farm management in these districts by his research, which was carried out before the rice acreage reduction policy and there after. The results are summarized as follows; The alluvial plain along, the northern shore of Tsuchiura inlet, the western part of Lake Kasumigaura, has a gentle slope, and it can be divided into upper alluvial surface and lower surface. The former is a coastal plain, which was formed by upheaval of the land that had been below the sea-level at the high water level period. And the land is semi-ill-drained field. The latter is a lake shore lowland that continues to be formed now and it might be subject to flood if it were not for the dikes. Therefore, the land is vast ill. drained field. At the northern shore of Tsuchiura inlet, the ratio of lotus fields to all paddy fields is more than 80 per cent, indicating one of the lotus root producing centers. But the writer found that the different introduction periods of lotus root and land conditions resulted in different agricultural management groups in these districts. First of all, the transition from rice growing to lotus root growing at the Tamura district began at an early stage because most areas of the district had vast ill-drained paddy fields with silt and clay. Thus, the farmers had already become producers skilled with high lotus root productivity before the rice acreage reduction policy was enforced. On the other hand, in the Okijuku district, rice has been a major crop because of large area of semi-ill-drained fields with silt and sand, and the transition to lotus root growing occured after the enforcement of the rice acreage reduction policy. Yields of lotus root per ten ares at the Tamura district is high at every class of the farm scales by utilizing suitable land conditions of ill-drained paddy fields and the production experience, and family income per ten ares exceeds 250, 000. This figure is three and one-half times as large as the average income of the rice growing farm. This is the economic basis of the formation of farmer groups specialized in lotus root growing in this district. On the other hand, yields of lotus root per ten ares the Okijuku district is lower than that of the Tamura district because the land is silty sand that is poor in keeping the fertilizer, and family income per ten ares ranges fro¥110, 000 to ¥170, 000 at each class of farms. It shows high profitableness, however, compared with that of the average rice growing farms. And the subsidy for changing rice to other crops has made up for the gap of profit against the Tamura district. Here the writer found that the lotus root growing at the Okijuku district depends upon the subsidy for changing rice to other crops under the rice acreage reduction policy.