1. The fertilizer application experiment was carried out for two years, 1979 and 1980, at the Hodogaya Country Club. We used four KORAI-greens. The amount of fertilizer applied in each plot was as follows:
1979 (10a/year) 1980 (10a/year) Plot N P₂O₅ K₂O Plot N P₂O₅ K₂O
25kg 25 25 25 20kg 20 20 20
35kg 35 35 35 30kg 30 30 30
45kg 45 45 45 40kg 40 40 40
(Note : a=100m²)
The summer of 1980 was cooler than usual years. And the influence of cool weather on the growing stage of KORAI-grass was investigated. We compared the cut dry weight, nitrogen, phosphorus, and potassium, plus starch and crude fat contents of grass of 1979 to these of 1980.
2. The growing stages of rice are considered in general to be divided into the following periods : (1) The vegetative growth period, (2) the reproductive period, and (3) the ripening period. The increase rate of dry weight of these stages is represented by an S curve. KORAI-grass, however isn't allowed to grow through the reproductive or ripening stages. Because it is cut more than 120-200 times per year (the cut height was 4-6mm.) the reproductive growth period is interrupted. The seasonal rate of cut dry weight could not be represented by an S figure curve. An inverted V curve would best represent it.
3. The air temperature throughout the year of 1980 was lower than that of 1979. This had a direct influence on the total grass growth. In August, 1980, the average temperature was down 4.43°C compared to the same month in 1979. This effect is seen severely in the yearly amount of cut dry weight of the 40kg plot in 1980 compared to the 35kg plot in 1979. The dry weight of the 40kg plot 1980 was down 13.5% compared to that of 35kg plot 1979. The cooler weather during the summer of 1980 had relatively little effect on the cut dry weight of KORAI-grass. It was found to be 12% less. The growth of KORAI-grass was influenced more by the low temperature from September to November rather than in the cold summer. The rate of decreased cut yield is as follows: September 54.0%, October 62.7%, November 100%. The average 59.4%.
4. Generally, cereal crops need less fertilizer during a long spell of rain or a cool summer. Heavy fertilization at these periods usually causes less grain yield. Therefore in those cases the amount of fertilizer use to be decreased. This is not applied in the case of golf links. The cut dry weight of the grass from the heaviest fertilized plot (40kg/10a) was much greater than that of the other two fertilized plot in spite of the long rain or the cool summer.
5. KORAI-grass showed active assimilation in the fine and cool weather of October (aver. temp. 17.5°C) and November (aver. temp. 11.56°C) . Starch accumulation content of grass was 24.00% in October and 36.06% in November. Later when the grass stopped its growth (during the winter) the assimilation and reservation of substance increased and was not influenced so much by low temperature.
6. The content of crude fat of general cereal crops is about 1.2%. However, KORAI-grass in golf links was observed to be 3-4 times higher than that of the above crops.

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1. This experiment was carried out by artificial inoculation to see under what field conditions the outbreak of Rhizoctonia Large patch in the Zoysia turfgrass lawn was most probable. Also examined was the influence of green keeping operations on the outbreak of this disease.
2. When the amount of the 100g/m² soil and wheat bran mixed with the culture of Rhizoctonia solani was inoculated into the field of Zoysia turfgrass lawn in the spring, the outbreak of the disease was observed only in the first and the following spring season but not in autumn.
3. To test the relationship between the outbreak of the disease and the amount of the inoculant, the soil and wheat bran mixed with the culture of Rhizoctonia solani of 50, 100, 200g/m² respectively was inoculated into the turf grass. As the result, the one least inoculated showed the highest degree of the outbreak, indicating no direct relationship between the outbreak of the disease and the amount of inoculant used.
4. In order to clarify in which season the outbreak of the disease most likely occurs, the inoculant of 200g/m² was inoculated into the turf grass lawn once or twice a month from autumn to spring. The obvious outbreak appeared in autumn and spring. It was also observed that all the inoculations from autumn to spring resulted in the outbreak of the disease in spring.
5. When the relationship between the outbreak of the disease and the resodding was examined using the inoculant with the amount of 200g/m², the newly layed turfgrass lawn was infected more quickly than the one without resodding because of the damage caused by the lifting and sodding.
6. To see whether or not the removal of the thatch containing the fungi would decrease the chance of the outbreak of the disease, the thatch of the turfgrass lawn, inoculated by the 50g/m² inoculant and developed with the fungi, was removed by means of vertical mowing. The result was that the outbreak of the disease was greater in the turfgrass lawn whose thatch containing the fungi was removed than the removed-free turfgrass lawn, because of the damage made to the turfgrass by the vertical mowing.
7. When the relationship between the outbreak of the disease and the vertical mowing was examined using the vertically-mowed turfgrass inoculated by 200g/m² inoculant, the outbreak of the disease in the vertically-mowed turfgrass was obviously greater not only in this disease season but also in the next. This was caused by the damage made to the turf-grass by the vertical mowing.
8. To see the relationship between the outbreak of the disease and the top-dressing, the following three cases were tested using the inoculant of 200g/m² : (1) the top-dressing after the inoculation, (2) the inoculation after the top-dressing, and (3) the inoculation without the top-dressing. The result showed that the top-dressing does contribute to the outbreak of the disease, especially when the topdressing was attempted after the inoculation.
9. When the experiment was made to show the relationship between the outbreak of the disease and the cored turfgrass lawn using the 200g/m² inoculant, the cored turfgrass lawn contributed to the some degree of the outbreak of the disease as the uncored turf-grass lawn, thus indicating no relationship between the two.

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The study was conducted to establish the method of chemical control of Kummerovia striata (Thunb.) Schindler, which is one of the most persistent and troublesome weeds of turf.
Mecoprop, triclopyr, dicamba and atrazine are applied to soil before the weed has not emerged, and complete kill effect was obtaind.
The weed was readily controlled by triclopyr, dicamba and [Catrazine+mecoprop], when they were applied in the seedling stage before its tight foliages have formed. But in its advanced stage, it was controlled by triclopyr and dicamba.
The herbicidal effectiveness of triclopyr was stable regardless of spray volumes or the SAA concentrations in the spray. However when triclopyr was used in higher dosage, it was phytotoxic to turf.
[atrazine + mecoprop] indicated the high selectivity and effectiveness to various kinds of weeds.

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The writers tested to clarify the herbicidal activities and behaviours of turf herbicides in soil.
And the following results were obtained.
1.The pre-emergence herbicidal activities to seven graminious plants [Alopecurus aequalis Sobol. var. Amurensis, Poa anna, Agrostis palustris, Echinochloa Crus-galli Bepuv. flumentaceae Trin., Digitaria cliaris (Retz. Koehler. Setaria viridis (L.) Beauv.]
Pendimethalin and benefin at 2.5-5 ppm, atrazine and simazine at 5-10 ppm, propyzamide, napropamid and asulum at 10-20ppm, and others at more than 20 ppm were effective on graminious plants respectively.
Atrazine and asulum were not effective on all graminious plants tested, so these herbicides were effective on some plants at low concentration, but on others at higher concentrations.
2. The pre-emergence herbicidal activities to six broad-leaved plants [Kummerovia stiata (Thunb.) Schindl., Chenopodium serotinum L., Daucus carota L., Raphanus sativa L., Amaranthus lividus L., Capsella bursapastoris (L.) Medik.]
Atrazine, simazine, mecoprop and triclopyr at 5 - 10 ppm, pendimethalin and benefin at 10 - 20 ppm were effective respectively.
Simazine, atrazine, mecoprop and triclopyr were not effective on all plants.
3. The leachings of the herbicides in the clayish loam soil.
Nitrofen, simazine, MK-616 and benefin were leached to a depth of 0-1cm in the soil. Terbutol, pendimethalin and chlothalmethyl were leached to a depth of 2-3cm in the soil. Siduron, napropamid, propyzamide, Orthobencard and atrazine wereleached to a depth of 2-3 cm in the soil. Triclopyr, mecoprop and bensulide wereleached to a depth of 4-5 cm in the soil. And asulum was leached to a depth of 8 cm in the soil.
4. The residues of the herbicides in the clayish loam soil.
Mecoprop, triclopyr and nitrofen were effective for about 30 days in the soil. Atrazine and simazine were effective for about 50 days. Bensulide, napropamaid, terbutol, chlorthal-methyl, benefin and pendimethalin were effective for more than 60 days in the soil.
5.The lateral movements of the herbicides on the surface of the clayish loam soil.
Simazine, nitrofen and chlorthalmethyl spread in a narrow zone, but asulum expanded in large area on the soil surface.

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The writers studied the behaviours of simazine and atrazine in the dormant turf (Zoysia matrella) in early spring, and the following results were obtained.
(1) These triazine herbicides were applied at 200g (la) in 200l (10a) of water to the turf which was 5 cm in plant height.
Simazine was much adsorbed onto the dead leaves of the turf and was not detected in the thatch layer under the turf leaves. But when simazine was applied on the turf after the removal of dead leaves or after cutting the leaves at 5mm from the ground, it was much distributed in the thatch and very little in the soil under the thatch layer.
Atrazine was not adsorbed onto the leaves so much as simazine, and was detected in the thatch. When atrazine was applied to the turf after the removal of dead leaves or cutting the leaves at 5mm from the ground, it was distributed in the thatch and about 2.5 cm in soil under the thatch layer.
(2) These triazine herbicides were applied to the turf at 200g (10a) in 100l, 200l or 400l (10a) of water with or without surface active agent (SAA) .
Simazine was much adsorbed onto the turf leaves when it was applied with small amount of water (100l), and simazine adsorbed onto the leaves was not easily desorbed with water. But its adsorption onto the leaves decreased with larger volume of water, such as 200l or 400l (10a) .Its adsorption onto the leaves increased with adding of SAA.
Atrazine was not adsorbed onto the leaves so much as simazine even in the case of small volume of spray water. But the amount of atrazine adsorbeb onto the leaves applied with large volume of water (200l or 400l) was much smaller than that of atrazine applied with small volume of water. The amount of atrazine adsorbed was also small when applied without adding SAA.
(3) The thatch and the soil collected from the turf area were applied with these triazine herbicides, and then young rice plants were cultured in these mediums.
The phytotoxicities of these two herbicides in the thatch were about 1/2 to the toxicities in the soil.
Their phytotoxicities in the sterilized thatch were 3 times higher than in the non-sterilized thatch, but the toxicities in the sterilized soil were about twice higher than in the non-sterilized soil.
(4) The amount of atrazine onto the thatch was about 8 times larger than that of atrazine adsorbed onto the soil. Atrazine adsorbed onto the thatch was not inactivated, but it was gradually desorbed with water, so the organic matter of the thatch plays an important role in the adsorption and desorption or these herbicides.

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The object of this study was to determine the effects of feeding and mating on the growth of the ovaries and oviposition of those scarab beetles which multiply only on turfgrass grounds (ex. Anomala osakana Sawada, Anomala schönfeldti Ohaus) and which feed on different types of vegetation as adults and as larvae (ex. Anomala cuprea Hope) . The adults just after emergence were fed turfgrass (Anomala cuprea Hope was fed persimmon leaves.) or reared only with wood flour. They were weighed each day after emergence, and the weight-decrease curves were examined. Weight of ovaries, number of contained eggs and quantity of solid substances were also determined for comparison and examination.
1) All body-weight-decrease curves for male A. osakana, whether given or not given turfgrass and whether reared separately or in pairs, showed similar patterns as in Fig. 2. When females are reared in pairs, whether fed turfgrass or not, the body-weight-decrease curve had a similar tendency to that of males. when a male is reared by itself, whether fed turfgrass or not, the rate of body-weight decrease dropped around nine days after emergence. It is considered that since the adult beetles are reared separately, they did not mate and oviposite.
2) The body-weight-decrease curve of males and females of A. schönfeldti were generally similar to those of A. osakana in every case.
3) When reared without feed, A. cuprea died 10-15 days after emergence in any case, and the weight-decrease curves were generally similar for males and females under the above condition. When fed during rearing, A. cuprea did not ingest food until 7-10 days after emergence and the weight dropped to about 75% of the initial weight. After they began feeding, they maintained a practically constant weight. Since each female of A. cuprea had been reared separately, the females deposited unfertilized eggs starting about 25 days after emergence. Both males and females lived about 40 days.
4) A. osakana and A. schönfeldti showed ovary growth even though they did not ingest food. The ovary weight of both species reached the maximum 6-9 days after emergence. When reared separately, A. osakana and A. schönfeldti kept constant weight after that. When reared in pairs, they lost weight rapidly afterwards. It is thought that this is due to mating and oviposition. A. cuprea did not take food until around nine days after emergence and did not show any ovary-weight increase. When they are fed, however, the ovary weight increased rapidly.
5) In A. osakana and A. schönfeldti, a similar tendency is observed between variations of the number of contained eggs and the ovary weight.
6) Adult A. osakana and A. schönfeldti are assumed to copulate without fail within the rearing cage, if they are reared in pairs.

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