A range of temperature, relative humidity, and velocity of air suitable for maximum production from dairy cows is called, in this paper, “the range of production environment”. According to some references, the range of production environment seems to be temperature of -12.2 to 23.9°C for Holstein and 4.4 to 26.7°C for Jersey, air relative humidity of 40 to 80%, and air velocity of 0.2 to 4.0m/sec. In order to study about how-to-make the appropriate production environment within a stanchion barn, distributions of air temperature and relative humidity were investigated in an experiment barn. It may be assumed that measurements were conducted under the steady state of air, because the experiments were carried out, during the winter season, in the barn with the openings closed after cows were all driven out. Findings may be stated as follows:
1) Air temperatures are almost uniformly distributed within the barn, although a little higher near the ceiling than over the floor.
2) Relative humidity over the floor is ramarkably higher than near the ceiling.
3) A group of higher relative humidities are found through the stalls and the maximum humidity is concentrated around the floor of the center stall, which may be taken as a principal type of humidity distribution in the case of the steady state of air within a stanchion barn.
4) In order to drop down the air humidity over the stall floor, it may bee necessary to select the unabsorbent materials for the floor as well as to arrange a sweep-in type manger, instead of a high-front type, in parallel with the main wind direction in summer.
5) The average air temperature is higher outside the barn than inside, while the average air humidity is higher inside the barn. Since those differences are clearly observed at the south of the barn, it seems that opening the south-side wall of the barn may contribute to improving the production environment.

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Until the recent time in the northern part of Japan, there used to be many disastrous years for rice production, whenever unseasonably cool weather occurred in the summer. Lately, however, especially since 1955, the rice production in that part has rapidly increased, and even in years of the cool summer it has become not so much decreased as in the past years. This is due to the recent advance in the technique of rice cultivation in cold districts. But, it can not be considered yet that the danger of cool domage has been completely swept away in cold districts. If the extremely low temperature would happen there, it is not difficult to suppose the occurrence of reduced rice production.
It is very important therefore, for the improvement of research on prevention methods against cool damage more efficiently, as well as for the deciding of the food policy, to estimate beforehand where the damage will occur or how much it will be, under the level of advanced technique and similar bad weather conditions as in former years. The author has designed a new method of estimating damage by cool weather and danger grade for cool damage of rice plants, and requested the technicians of all prefectures in cold districts to try to get the estimation by using his method. As his method of estimation, however, only indicates the basic ways and means, the technicians in each prefecture must decide by themselves the most suitable values for the conditions tentatively given in this method. The results obtained in every prefecture will be published elsewhere.
The most important parts of the method reported in this paper are as follows
1. There are three types occurring in cool damage, i. e., delay, injury, and mixed types.
When the growth of rice is considerably delayed mainly due to unseasonably cool weather during its vegetative growth period, the ripening period comes during the low temperature of autumn and results in a reduced crop. This is called the delay type of cool damage. The preiods in which rice is most sensitive to low temperature during its growth are those at the reduction division stage of reproductive cells and at the flowering stage respectively. The rice plants suffer from non-ripened grains due to a temporary low temperature during such reproductive growth periods. This is called the injury type. If the above-mentioned two types of cool damage occur simultaneously, it is called the mixed type.
Therefore, the next three relations may be important indexes for estimating damage, i. e., relations between (1) the decrease rate in the production and the air temperature during the ripening period, (2) the decrease rate and the air temperature at the reduction division stage, and (3) the decrease rate and the air temperature at the flowering stage.
2. The respective values of these three relations can be prepared from many past results of investigations and experimental reasearch in each prefecture.
The decrease rate may be easily got by both these relations and the course of air temperature given in one of the years in which cool damage occurred in the past.
3. First of all, however, it is necessary for this estimation to decide the growth stage of rice plants. The flowering stage is almost the same as the heading stage. The reduction division stage is during a period from 10 to 15 days before the heading stage, and the ripening period is the period of 40 days after heading. Then, if the heading stage can be fixed, these three growth stages may be easily decided. Since the accumulated air temperature from sowing to heading is said to be constant for each variety of rice plant, the heading day of the rice plant concerned can be fixed by summing up the daily air temperatures from sowing day till the day on which the accumulated value reaches the constant.
4. The result of the estimation in a prefecture, in practice, is obtainable by summing up the results in many small areas such as towns and villages. And the

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In this paper, the characteristics in the regional change of the dependence of rice yield on cool weather conditions in a summer season were investigated on the basis of both the relationship between the rice yield and cool weather conditions and data on the occurrence of low air temperature in the season. The results so obtained may be summarized as follows
1. Aomori pref. was found to be divided into five groups from the standpoint of the weather dependence of rice growth (see Table 3). The rice growth in the most sensitive region to the delay-type damage (caused by the delay of the heading due to lower air temperature through the vegetative growth period) was recognized to be also greatly affected by such a lower air temperature in the heading period as it injures the young head of rice.
2. Two factors, daily mean air temperature during the growing season of rice and difference in day between the actual heading time and the critical heading time assuring the perfect ripeness of rice grain, were took into consideration for establishing the measure of forecast of the yield from weather conditions. Using the accumulated air temperature for the period from the sowing to the heading (it changes with the variety of rice and the type of nursery bed), the measure was applied to forecast the degree in decrease of rice yield by such weather conditions as experienced in years with cool weather damage of rice growth. The results indicate that the rice yield at 1953 and 1954, in which the cool weather damage was observed in Aomori pref., should become about 96per cent and 93per cent of the mean yield in years with normal weather conditions, respectively, if recent improved techniques were used at these years. The above fact seems to imply that the present techniques in rice growing is valuable to help the stabilization of the yearly variation in rice yield.

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At Shimamatsu maneuver field (Hokkaido district) with the area of 5, 450ha, the soil survey was made to clarify the influence of the frequent passage of heavy vehicles on soil properties such as a hardness, infiltration capacity, depth of frozen soil and so on, during the period from 1962 to 1963. 21-surveying plots were selected from the whole field referring to the air photographs. These plots were classified into the three grops as follows: group I was the forest land with dense vegetation, group II the land with little waste vegetation, and group III the extremely waste land.
The results may be summarized as follows:
1. The degree of slope in the field was from 1/8 to 1/4.5 with the mean value of 1/5.6. The soil at surveyed plots was the sandy loam belonging to volcanic ash series. The vegetation in the group III has been extremely wasted and become the bare-land because of the frequent passage of heavy vehicles. The soil hardness was larger for the group III than for the group I.
2. The infiltration test of soil samples using a rain simulator indicated that the infiltration capacity was larger for group I than for the group III. As shown in Fig. 5. the rain water applied to the samples from the group III flowed out immediately as a runoff after the beginning of the rain. This fact implied that the water-holding capacity for the group III soil was negligibly small. The runoff for the group I was hardly observed, and the most of rain was infiltrated into the soil. On the other hand, the runoff for the group II occurred in parallel with the infiltration. It was also found that the amount of runoff increased proprtionally to the soil hardness.
3. The depth of frozen soil layer was observed to be smaller for the group I than for the group III, because of the existence of dense vegetation at the group I.
4. It is reasonable to point out that dam making may be effective to prevent the soil erosion from the waste land caused by the frequent passage of heavy vehicles, but the adoptation of the tree planting method may be more effective for the soil conservation at extremely waste lands.

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In warm districts of Japan, we have a great many of citrus plantations. Recently, many planters in these districts are desirous to enlarge their orchards to increase their incomes.
The local climate, however, is markedly various in each location even in a small area of just one orchard. Especially in winter the cold air subsides to the lower parts of the slope land, making such places very dangerous for citrus plantation because of cold damage. Therefore, when planters plan to make new citrus orchards, it is very important to choose suitable locations, especially to omit, in their planed location, all dangerous spots where cold damage may occur. Therefore, it will become an important problem for the planters to find such dangerous spots before planting citrus trees.
The author offers a new method of determining dangerous spots for new plantations. The method is based on the following four factors:
(1) return period at the nearest meteorological observatory,
(2) the relationship of the low air temperatures between the investigating area in question and the observatory,
(3) the critical minimum temperature limit, and
(4) the distribution of low temperatures in the location.
1. The return period of the minimum temperature in winter, which will happen once every 10 years, can be got from the statistics of the past 30 or more years at the observatory near the investigating location.
2. The relationship of low temperatures between the observatory and the base station newly set up in the location may be obtained from the regression formula. This formula is made up from the minimum temperatures registered at the two stations on clear, calm nights during which the most cold damage usually occurs.
In order to carry out this investigation, the minimum temperatures at the new base station built on the investigating location, have to be observed every day during the winter.
3. The critical minimum temperature causing the cold damage will be decided through investigating both physiological and economical conditions in each prefecture in warm districts. The critical minimum temperature from a physiological point of view is shown to be -7°C, from the past records of investigations and experimental researches.
4. The distribution of the minimum temperatures in the investigating location has to be got from the result of new observations on several clear and calm nights.
To make clear this distribution, many new observation points must be set up around the entire area of the location. From these results the planters will be able to show some spots apt to be relatively colder than other spots on clear and calm nights in winter.
Through the discussion of these results, some dangerous spots in the lacation may be pointed out.
The author emphasizes, furthermore, that a more important fact is the pointing out of practical measures to improve microclimatological conditions at such dangerous spots, which make them safer by, for example, arranging some belts of hedges or woods on upper parts of the slope to change the cold air flow, or cutting them off on the lower parts to exhaust cold air accumulated there.
It is very important, therefore, not only to point out the dangerous spots in the investigating location, but also to give practical ways and means for clearing away a so-called cold air pond to explain. how and why such cold air ponds are created.

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In order to obtain a preliminary information about the artificial acceleration of snow-melting, daily meteorological data at Takada (37°06′N, 138°15′E) for the period from 20 January to 27 March in 1962 were processed on the basis of the heat balance method. The heat balance equation at the snow surface in a melting season may be approximated by Eq. (2). The following methods were adopted to determine the daily amount of each heat balance item.
In determining the absorbed short-wave radiation, R_s(1-a), the value of albedo, a, was assumed to be 0.8 for a fresh snow surface and 0.5 for a granular snow surface. Effective long-wave radiation R_e, was calculated from Eq. (3). Using Eqs. (6) and (7), sensible heat flux, L, and latent heat flux, lE, were determined from a sensible and latent heat transfer coefficients and the differences in temperature and water vapor pressure between the snow surface and the standard height (1.5m). Eq. (8) was used to get the value of sensible heat transfer coefficient. Table 1 shows the comparison of the wind dependences of sensible heat transfer coefficient calculated from Eqs. (8) and (9).
Figs. 1 and 2 present the seasonal change in quantities relating to the heat balance and meteorological conditions during the snow melting season. The characteristic in heat balance at the snow surface on days with the snow melting converted to water depth over 10mm per day is shown in Table 2. This table indicates that the contribution of net radiation, S, to a snow melting is large in comparison with other items and that the contribution decreases from about 100per cent for the early stage of a snow melting to about 50per cent for the latter stage. On the other hand, the contribution of heat (L+lE) transferred from air layer to the surface was found to increase somewhat in the latter stage (see Table 2).

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