Auxins and inhibitors in the buds of Pinus strobus were investigated. Auxins and inhibitors in ether extracts were measured by means of paper chromatography and Avena straght growth test.
On chromatographing in isopropanol-28%, ammonia-water(8:1:1), a growth promotingzone (Rf 0.0_??_0.5) and a growth inhibiting zone (Rf 0.5_??_0.9) were detected in the acid fraction and a inhibiting zone (Rf.0.3_??_0.9) was detected in the neutral fraction.
In the acid fraction, two auxins (Rf around 0.20, Rf around 0.25) and one inhibitor (Rf 0.54_??_0.84) showing positive reactions by EHRLIOH reagent and GORDON & WEBER reagent were found.
It may be suggested that they are indole compounds.
Chromatography reveals growth promoting substance which corresponds in Rf with IAA, while no color was observed upon application of EHRLIOH reagent etc. to the chromatogram.
The buds were treated with 1, 000 ppm solution of Tryptophane for 48 hours at 25C° in the dark.
After the treatment, auxins and inhibitors were measured.
Four auxins (Rf around 0.20, Rf around 0.25, Rf around 0.30, Rf around 0.41) andtwo inhibitors (Rf around 0.53, Rf 0.54_??_0.84) showing positive reactions by EBRLIOA reagent were found in the acid fraction.
Among them, auxin of Rf around 0.41 was identified as indoleacetic acid(IAA)comparing
it with Rf values in four solvents and color reactions in three reagents of synthesized IAA controls.
From these results, it may be considered that Tryptophane-IAA converting enzymesystem exist in the buds and these buds produce IAA from Tryptophane even without the addition of Tryptophane.
It may be suggested that the quantity of IAA obtained from the untreated buds might be too small to show the positive reaction by EHRLICH reagent etc.
The relation of the new compound (Rf around 0.30, Rf around 0.53) to Tryptophane was not established.

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In the former experiment (MITSIIDERA and NUMATA 1960), the first factor for the fair growth of bamboo stand was analysed statistically. As the result of such an exper-iment and analysis it was the amount of rainfall in the growing season of bamboo sprouts (May-June). Using a two-year-old bamboo (Table 1, Figs. 1, 2), the water economy of bamboo was examined by the new transpirometer (Fig.3). Meteorological values and the amount of transpiration are shown in Table 2. The variation of the amount of transpiration is elucidated by the recording of the transpirometer (Figs.4, 5, 6). The relationships between the amount of transpiration and the air temperature or the relative humidity, and the one between the increment of transpiration and the relative humidity are shown in Figs. 7, 8, 9. The characteristics of the soil moisture meter used in the experiment (Fig.10), the daily variation of the soil moisture content in the field tanks (Fig.11), and the relation of the calibration of the instrument to the amount of transpiration (Fig.12) were examined.
According to these data and the variation of the water content of bamboo leaves, the soil in the root circle 20 cm deep became dry at first in the morning, then the amount of transpiration reached to the maximum 1 hour later, and at last the water content of leaves dropped.
The formula for the water economy is as follows:
M=(P+C)-(I+E+R)
where M: soil moisture, P: precipitation, C: codensation water, I: interception,
E: evapotranspiration, and R: run off. Here we assumed P=160 1/m², C=O, 1=16 1/m², R=48 1/m², and E=158 1/m². Then M=-62 1/m². Though we assume I=10% of P at the lowest estimate, M showed the negative value.

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Some effects of two kinds of long day treatments on the growth of Abies Sachalinensis seedlings were tested for about 12 months by sand culture with five kinds of solutions containing mineral nutrients(Table.1).
Supplementary light for long day treatments was given by the fluorescent lamps (about 1, 000 lux) for four hours (from 5 to 9 p.m.) and for seven hours (from 5 to 12 p. m.) every day.
Experimental results are shown in Figs.1 to 3, and Table 2. Under long day treatments, growth of seedlings was accelerated with all kinds of nutrient solutions, especially more in stem than in root.
The effect of long day was the most remarkable with the 2 × standard solution in which long day seedlings were about 2.6 times of control plants(natural day length) indry weight. And it decreased in the following order; 2×N, 2×P, 2×K, and standard (Table 2).
Four hours a day of supplementary illumiation seemed to be more effective in the following three solutions; 2 X standard, 2×N, and 2×P.
It should be noticeable, however, that long day seedlings had a tendency to develop for k-shaped lateral shoots on their tops in consequence of faster growth of their lateral buds and to form irregular shapes (Fig.2).

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Some effects on the mineral nutrition and shade treatment were examined in slash pine (Pinus elliottii) from May 30 to Oct. 18 in 1960. Nutritional tests were carried out by water culture (Fig.1). The kind of experimental sections and the components of each nutrient solution are as shown in Table 1-2. The slight shade were enclosed a marsh-reed screen and severe shade were enclosed double marsh-reed screens (Photo. 1_??_2).
Results of experiments are shown in Fig.2_??_3 and Table 3. In the control shade, P and N-deficiency symptoms appeared severely, the color of leaves in minus P became dark green and minus N became yellow. Both the lower leares were withered.
In the slight shade, K, P and N-deficiency symptoms not appeared and the seedlings grew up tender.
In the severe shade, K, P and N-deficiency does not appeared and the growth verey considerably failed as against control.

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A model experimeut by means of simplified channel bed (Fig.l)was carried out in order to study for the mechanism of the movement and accumulation of gravel on a stream bed. The results of a preliminary experiment were very complicated against our expectation, and so the observation of the process of this experiment led us into the introduction of an idea of critical discharge. We experimented to study for the relation between slope and critical discharge. The results were as Fig.2

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