In general farming in Japan the biggest item among the agricultural production cost is the expense for fertilizers. In the case of dairy farmers it is not the fertilizer cost but the expense for concentrated feedstuffs which, on average, is extraordinarily high and by far surpasses the expenses for fertilizers. Both items should be considered together, because in both cases the farmer spends money to buy nutrients which he utilizes to increase his agricultural production: a) plant nutrients, b) nutrients for the animals (TDN). From the point of view of farm economics the best combination of purchased fertilizers and concentrates is reached when the highest effect is obtained at the lowest possible cost. Under this aspect, a fertilizer experiment on green maize, carried out from 1956 to 1958 by the Iwate Pref. Agr. Ex. Stat., was evaluated with the following results: 1) Application of fertilizers up to rates of 120kg/ha N, 186kg/ha P_2O_5 and 204kg/ha K_2O, in addition to 15 t/ha farm-yard manure (FYM), gave strong yield increases, so that the amount of Total Digestible Nutrients (TDN) in the forage was sufficient to feed 5 dairy cows with 15kg milk production per day over a period of 1 month from the green maize obtained from 1/10 ha. Only some additional soybean cake was necessary to balance the TDN/digestible crude protein ratio (=case A). 2) If the same milk yield from 5 cows during 1 month should have been obtained from the forage produced on the experimental plot "FYM only", it would have been necessary to feed more additional concentrates (=case B). 3) Comparison of expenses for concentrates and fertilizers reveals that in the case of this experiment the application of the above fertilizer quantities would reduce the cost of concentrates from 53% (case B) to 14% (case A) of the gross income from milk whereas the fertilizer cost would be not more than 5% of the gross income from milk in case A. 4) Thus the cost of milk production would be greatly reduced due to high application of fertilizers. In this case the expenses for fertilizers +concentrates would decrease from 53% (in case B) to 19% (in case A) of the gross income from milk. 5) In the example of this experiment, therefore, the highest fertilizer application combined with the smallest amount of concentrated feedstuffs was the most profitable combination. 6) If it is possible to generalize this result, one might say: Fertilizer application to forage crops-in high amounts and well-balanced nutrient ratios according to the needs of the plants-is more profitable than the usual practice (in Japan) of heavy use of concentrates.

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Methods of renovation were studied on the shore of the River Abukuma for 4 years since 1956. Fields of orchard grass, red clover and these mixtures were divided into ploughing, non-ploughing and band-ploughing plots. The growth of forages among plots were not so different. The stattistical significances of green yields and weight of weeds, couldn't be recognized between each treatment plot. The experimental fields were flooded two times of both July and September 1958, when the River Abukuma was inundated by gale or rains. The regeneration of forages seemed to be influenced by amount of soil invested by flooding. The relation between green yields and surface cover of forages was presented by r=0.42, and the correlation coefficient between surface cover of forages and weeds was r=-0.83.

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Italian ryegrass is the suitable plant for the warm and humid climate in winter, and one of the most useful fodder in the south-western district of Japan because of its rapid growth. However, it has a fault that it is difficult to pieces the soil clod at cultivation for much fine roots. The influence of nitrogen fertilizer on the growth is the most, Phos-phorous is next and potassium is almost not effective. The growth and yield are increased by the increasing amount of nitrogen and phosphorous fertilizers, but not increased by potassium, moreover calcium. The similar effect of fertilization as shown in the top was obtained in the root. Content of nitrogen and carbon in the root is decreased by want of any one element in fertlizers. Nitrogen content in the root is increased by the increasing amount of nitrogen fertilizer, but decreased by the addition of calcium, and also shown the decreasing tendency by the increasing amount of phosphorous and potassium fertilizers and with calcium. Carbon content in the root is increased by the increasing amount of nitrogen and phosphorous fertilizers, but not with calcium, and also decreased by potassium and with calcium. Carbon and nitrogen ratio in the root is almost 50 to 60.

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In this report results of the investigation are presented which has been conducted in 1960 on an area of experimental pasture grassland (Ladino clover, Orchard grass and Ryegrass) at our college ground. The purpose of this investigation was to make a study of sampling in the case of yield and coverage survey, especially with reference to size and shape of the sampling unit, and of testing the applicability of the field experimental design to the pasture grassland. A rectangular area, 14x16 meter, was subdivided into 224 plots, each 1 meter square, and coverage of Ladino clover and Orchard grass was weighted in every plot and the variation of various sizes and shapes was tested. Besides, adding the study of size of quadrat to the above to judge condition of the grassland in present and in furture by the distribution type of grass coverage, the following results were obtained. 1) Over 40cm square size of quadrat is fited to determine the distribution of coverage of Ladino clover. 2) The size of quadrat becomes the larger, the experimental error to the coverage and yield of Ladino clover becomes the fewer. But in case of Orchard grass which is recessive, the size of quadrat has the fewer effect on reducing the experimental error to the coverage and yield. 3) The ratio of the sampling area to all experimental one was calculated by the coverage and yield of Ladino clover. The ratio of the coverage and yield was 1.8% and 4% respectively. But this ratio includes 10% experimental error. In order to determine the coverage and yield of pasture grass of the area accurately, a vast numbers of units are required.

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The protective effect of EMP dust on the snow damage of Renge plant (Astragalus sinicus L.) caused by Sclerotinia trifoliorum Eriks. was studied in 1959-1960. Results were as follows: 1) 500 grams per are of EMP (1.0% Hg), dusted on the field at the early stage of breaking out of the disease was remarkably effective comparing with 3.8kg per are of lime to lessen the area of the damage and to increase Renge yields. 2) The minimum concentration of Hg in EMP dust effective to sclerotinia rot was found to be 0.4-0.5 per cent. 3) Some trials were conducted concerning concentration of Hg and time of dusting under good conditions for attacking of sclerotinia rot. EMP dust of 0.5% Hg was not so effective when used at the stage of apothecium formatinn, but showed remarkable effects when dusted on vigorously spreading mycelia. EMP dust seems, therefore, to have a notable sterilizing power to mycelia, too. 4) Talking about the tests conducted in the glass-house, dusting of EMP on sclerotia scattered on the sand was greatly effective to prevent apothecium formation. When dusting was conducted after the formation of apothecia, EMP led apothecia to blacken and wither, and to be inefficient to discharge ascospores. These effects of EMP was more remarkable in the dust of 0.5% Hg than that of 0.3%, and the percentage of mortality of apothecia was greater by dusting at the late stage of apothecium formation than the early stage. From these results, it may be said as follows: When the damage is expected to be serious, the concentration of Hg should be at least 0.5%, and if the dusting is performed only once, you had better aim at curative effects by treating mycelia than protection by treating sclerotia or apothecia.

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[in Japanese]

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[in Japanese]

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