This study was made of variation of chemical composition of Bahiagrass (var. Pensacola) at successive growth stages and herein included the effects of heavier fertilization and meteorological factors in growing season. 1. The percentage of crude protein, crude fat, crude ash, phosphorous and potassium decreased with advanced stages of growth and decreasing rate was high until the beginning of heading. The percent of crude fiber and nitrogen-free extract increased as the plants grew older, the greatest variation being recognized after heading. 2. The crude protein content was improved by heavy nitrogen fertilization but the crude fiber, crude fat, crude ash and mineral content did not generally changed. The nitrogen-free extract was reduced with application of much nitrogen. Heavy application of phosphorous. and potassium did not affect chemical composition of Bahiagrass. 3. Seasonal variation in chemical composition was as follows : Crude protein and crude ash were comparatively low in summer and rose with the advent of cooler fall weather. The percentage of crude fiber exhibited the opposite trend from that of crude protein. The percentage of nitrogen-free extract and crude fat showed no distinct seasonal variation. The nutritionally important constituent of Bahiagrass was lowest during the hot season of August.

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The authors carried out an investigation on the growth progress and nutriment variation of Koiwai turnip, under the same culture condition from Oct. 8th (1965) to April 21th (1966), and the results obtained were as follows : 1. The fresh weight of top (leaf-blade) attaind to peak early in November. There-after, it diminished gradually in the course of defoliation of leaf-blade, transference of nutriments from top to root or consumption due to the respiration etc, and increased gradually according to the process of the growth of a flower-bud again. 2. The fresh weight of root showed a tendency to increase during the wintering processes under snow-drifts, and it diminished to get in the growth season of a flower-bud, but dry weight of root did not always increased under snow-drifts, and the storage nutriments (mainly total sugar contents) decreased to exhausting in the causes of the respiration etc. 3. As total weight of top and root attaind to maximum in mid December not only in the fresh and dry matter but also in the storage nutriment components, this season seemed to be the time of harvest. 4. Results obtained in comparing storage nutriments of chopped and non-chopped top during preservation for about 90 days after harvest showed that the nutriments of non-chopped top were transferred to root giving lower fresh weight loss of the root and slight gains of dry matter and storage nutriment of it than chopped top. But dead leaf-blade has no utility during preservation, it seems to be profitable to make best use of chopped top after harvest and to preserve topless root only.

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1. Present authers investigated the external charactors and geographical distribution of D. ianthes, which is a micro-lepidopterous insect belonging to the family Gelechiid and an important pest of Ladino clover in Japan. 2. D. ianthes is widely distributed throughout such areas of Asia and Africa as Japan, Formosa, Malaya, Java, Celebes, India, Ceylon, Reunion, Mouritious, Seychelles, Egypt, East-Africa etc. In Japan, it is distributed in Kyushu, Shikoku and most part of Honshu but not distributed in the northern part of Honshu and Hokkaido. D. ianthes is considered to be a southern species. 3. The northern limit of the distribution of D. ianthes exists in Honshu of Japan as shown in Fig. 6. The limiting line is supposed to run from the Pacific coast of the northern Miyagi prefecture to the Japan Sea coast of the south-western part of Niigata prefecture through Fukushima prefecture and the northern Nagano prefecture. 4. The limiting line is generally coincided with the isothermal line of 11℃ or the 50cm line of maximum snow depth. It may be concluded therefore that the distribution of D. ianthes in the northern limiting zone is much influenced by the low temperature and snow in winter.

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Present studies dealt with the effects of shading during various developmental stages on growing rates of plant and starch contents in tap root of alfalfa, var. Du Puits. The experiments were carried out in combination of the shading-rates (0, 65 and 80%) with the various developmental stages (1-3, 3-6, 6-9, 9-12 and 1-12 leaf stages), and these plants were examined at 59 days after the sowing. The results obtained were summarized as follows : 1. The growing rate of the plant height was evidently suppressed by the shading in 1-3 and 3-6 leaf stages. On the other hand, this growing rate was considerably promoted by the shading in 9-12 leaf stages. 2. The growing rate of the branch-length was promoted by the shading in later developmental stages. 3. The dry yield of the plant decreased with shading in most stages, except the top of the shading plants in 6-9, 9-12 and 1-12 leaf stages. 4. Accumulation of starch grains in tap root was obviously disturbed by the shading in 9-12 and 1-12 leaf stages. 5. From these results, it is concluded that the growing rates of plant and starch contents in tap root are largely varied with the shading in each developmental stages.

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Sub clover and ladino clover seeds were introduced into separate plots established in an existing orchardgrass sward of low produtivity. Simple methods were used in preparing the plots and applying the seeds. Both clover species produced marked improvements : total herbage yield, chlorophyll content of orchardgrass leaves, and the inorganic N content of soils were significantly higher in clover-containing plots than in cheek plots without clover. Laino clover disappeared during the second summer. In contrast, stands of sub clover were maintained for the three year duration of the experiment due to the appearance each autumn of many volunteer seedlings. It is concluded that sub clover may prove useful for the improvement of low productive swards including native Japanese grasslands.

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The aim of this study is to make clear whether the yield of Rhodes grass sown on such a compacted soil condition as shown in our previous paper, decreased or not in comparison with that sown on a loose soil condition. The soil compaction treatments (loose, middle and compact) were conducted on two texture types of volcanic ash soil (silty clay loam and loam) by tractor traffic and Rhodes grass was cultivated. The results obtained are as follows : 1. As soil bulk density increased, the dry matter yield of Rhodes grass also mounted on both soil types. This fact was recognised more clearly in 1st cutting than the others. 2. No significant difference was found in the root distribution within 0-30cm soil depth among the soil compaction treatments. 3. As soil bulk density increased, soil air voids at pF 1.5 in 0-15cm depth decreased, but the measurements of "compact" plot soil were 13-16% on SiCL and 6% on L soil. Air voids in 0-15cm soil depth of "compact" plot were over 10% on both soils throughout all growing period. 4. Available soil moisture percentage per soil volume in 0-15cm depth was higher in "compact" plot than "loose" plot. 5. NO_3-N or NO_3-N+NH_3-N contents per soil volume of "compact" plot was more in surface soil and less in subsurface soil (10-30cm) than "loose" plot. 6. We presumed that the reasons for higher yield of Rhodes grass on more compacted plot were attributed to higher moisture and NO_3-N contents in the surface soil on that plot. 7. Based on the above facts, it can be said that the yield of Rhodes grass sown on such a compacted soil as shown in our previous paper, will not decrease in comparison with that sown on a loose soil.

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With a view to making clear the relationship of soil compaction that resulted from sod-sowing method and growth of Italian ryegrass, the soil compaction treatments (loose, middle and compact) were conducted on two texture types of volcanic ash soil (silty loam and loam) by tractor traffic and Italian ryegrass was sown following soil cover. The results obtained are as follows : 1. No significant differences in plant height, number of tiller and dry matter yield of Italian ryegrass were found among the soil compaction treatments on both soil types. 2. The higher soil compaction treatments caused the harder soil, but did not cause significant difference in the root distribution within 0-30cm soil depth. 3. Soil air space at pF 1.5 in the most compacted layer of "compact" plot was 11% on SiL and 6% on L soil, and that at the field was over 10% on both soil types within our measurements. Therefore, it should seem that the soil air reduction by higher soil compaction trearment did not hamper the growth of Italian ryegrass. 4. Available soil moisture percentage per soil volume in 1-6cm depth was higher on more compacted plot, but significant differences in NO_3-N or NO_3-N+NH_3-N contents per soil volume in 1-6cm depth were not found among the treatments. 5. It seems the reason for no significant difference in growth and yield of Italian ryegrass among the treatments, whereas the higher soil compaction treatment caused the higher yield of Rhodes grass as reported in our previous paper, lies in little difference of available nitrogen content in the surface soil (1-6cm), and which resulted from slower nitrification and less leaching of No_3-N into the subsoil under cooler growing season. Anyhow, it has shown that the yield of Italian ryegrass sown on such a compacted soil as shown in previous paper would not decreased in comparison with that sown on a loose soil.

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