The study was evaluted the shoot characteristics of “Springs” creeping bentgrass under the pot sand culture, The “Springs” was selected the seedling from radiated dry seed of “Penncross” bentgrass,
(1) Shoot growth of Springs was inferior to Penncross every times, but there were showed no significant differences.
(2) There were no significant differences in average leaf blade length within two cultivars evermore. Leaf blade length tended Springs to be longer than Penncross. However, the width of Springs leaf blade was narrow every time. Other leaf characteraistics, ligule, auricles collar were not different.
(3) The internode length of Spings stolon was as short as about 20 percent and the width of Springs' internodes were as slender as about 10 percent.
(4) Springs creeping bentgrass forms a uniform, very dense, high quality turf, because it has narrow leaf blade width and short internode length. It will be utilized on golf greens that will be mowed very close.

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In this experiment I investigated about the influence that the differerce of autumn season seeding time affect the growth of next year, and the summary of these results are as shown under.
(1) On over wintering germination, the limit of the seeding of the good regrowth in early spring is the middle of September seeding, in case of miss this period it is proper that the seeding of dormancy period after November.
(2) In the germination rasio of next year and the germination period there is no difference between the dormancy period seeding and the seeding on snow, and generally they grew better than the seeding from late in September to middle of October.
(3) In low temperature time of early spring KBG has the most powerful regeneration of the three grasses (KBG, CRF, CB) . But as the temperature rises, CB growes remarkably. However CB is easy to suffer from snow molds, and doesn't agree with the September seeding.

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Ecological observations were carried out concerning the fungus of the fairy rings on the turfgrass, Zoysia matrella L., in the soil. Their results are as follows.
The fairy rings grow at the annual rate of about 100 cm, forming concentric circle. With the ring moving toward outside, the myceria of fungus, situated outside the ring, are not extended over 30cm from the outside edge of the ring. On the other hand, the myceria which are inside the ring die gradually from inner fungus in the concentric circle, leaving only the fungus within 30 cm from the inside y edge of the ring alive.
On greens and tees of golf courses, the fungus of the fairy ring is usually found in the soil, within 9cm below the surface of the earth, containing organic compounds, while no fungus is found in the soil under 9 cm containing no organic compounds.

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This experiment was to establish the inoculating method of Basidiomycetes to turfgrass, and to investigate the interaction Basidiomycetes and the growth of the turfgrass.
1. Basidiomycetes offered this experiment was seemed Lepista.
2. The turfgrass was inoculated by the method of laying the pathogenic soil under the turfgrass. The pathogenic soil means the mixture of sand and bark-organic-fertilizer was inoculated Basidiomycetes and had been incuvated at 25°C for two weeks.
Incuvating temperature after inoculation is very important. Two weeks incuvation at 25°C after inoculation let the turfgrass restrain and wither. But under the incuvating condition at 15°C, nothing is wrong with the turfgrass.
3. Inoculating to the foliage of the turfgrass, the myclium of Basidiomycetes spread the foliage, but the turfgrass had no change. Inoculating to the roots of the turfgrass, the foliage of the turfgrass withered, and the roots got yellowing and withered. Judging from these mentioned, it's seemed that Basidiomycetes influenced the roots of the turfgrass.

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1. Because of the spraying of some herbicides on the Zoysia turfgrass, it is supposed that the turfgrass becomes susceptible to the outbreak of Rhizoctonia large patch.
Therefore, this experiment was carried out to find out the relationship between the outbreak of this disease and the spraying several different herbicides.
2. To see whether the outbreak of this disease happens more frequently under the in fluence of the spraying of several preemergent herbicicides, the herbicides were sprayed on the turfgrass respectively prior to the occurrence in spring. And ofter that, the pathogen was inoculated to the plots by the artificial method.
As the result of this, in the first half of the occurrence, the degree of infection of plots with CAT 0.3g (/200/m²), SAP 2cc, Siduron 2g and TCTP 3g became higher than the nontreated plot, while the plots of Butamifos 2g, Propysamide 0.6 g and Orthobencarb 1.5cc showed the same rate of infection as the nontreated plot.
In the latter half of the occurrence, the leision, which had already occurred, spreaded on all plots, at the same degree as on the nontreated plot.
3. Since it was supposed that the disease would occur naturally on all plots after the next season, the same herdicides were sprayed on the same plots respectively prior to the occurrence in autumn.
In the first half of the occurrence, the leision appeared more largely on the plots of CAT, SAP, siduron and TCTP than the nontreated one, as was the case last spring. In the latter half of the occurrence, however, the leision of all plots spread at the same rate.
The same experiment was performed again in the next spring. This time, throughout the occurrence, the outbreak of the disease on all the plots appeared at the same degree as the non-treated plot.
Incidentally, the disease appeared to a larger extent on the outer edge of the plots of CAT, SAP, siduron, and TCTP than other plots. And the plots of CAT, SAP, Siduron and TCTP have deep caused by poor drainage.
In consegnent, it can be said that throughout the entire period of the occurrence the turfgrass does not become Susceptible to the outbreak, of Rhizoctnia large patch as the result of the spraying of herdicides.
4. This conclusion can be supported dy a similar test conducted at another place. In this case, the same degree of infection was witnessed on the plots of CAT, Orthoben carb and Butamifos as on the non-treated one.
It was also tested whether the leision, which had already occurred, would spread further as the result of the spraying of the abovementioned seven harbicides. No specific differences were witnessed in this test between the plots with herbicidal treatments and the non-treated plot.
5. To see the effect of some post-emergent harbicides on the further spread of the disease, the herdicides were sprayed in spring and autumn on the already occurred leision.
The plots of MCPP 1.5cc (/200cc/m²) and Asulam 1.5 cc showed the same degree of infection respectively as shown in the nontreated plot, although the phytotoxity of both herbicides appeared clearly throughout this test.
Therefore, it is supposed that the effect of post-emergent herbicides on the spread of the disease is rather minimal.
On the other hand, the spread of the leision to which DSMA 0.5 g was sprayed, was clearly inhibited. Therefore, it is supposed that DSMA has a contsolling effect on this disease.

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The dormancy of annual bluegrass seeds was broken when they are stored in the humid condition at low to medium temperatures (5°C -18°C) for about 10 to 15 days.
The seeds which overcome the dormancy were able to germinate under the light, but not under dark condition.
The most seeds which lay in surface or subsurface soil under upland condition during the summer were able to germinate in early autumn.
The effective herbicides in Zoysia turfs for annual bluegrass control without phytotoxicity were simazine, atrazine, orthobencarb, asulam, terbutol, napropamid, propyzamide, chlorthaldimethyl, chlorphthalim, benefin, bensulide, butamifos, pendimethalin, acephenone, methyldymrone, lenacil, dichlobenil, 2, 4-D, MCPP and trichlopyr by pre-emergence soil treatment, and simazine, atrazine, asulam, propyzamide, chlorphthalim and lenacil by early post-emergence treatment (two leaf stage), and atrazine, asulam and lenacil by late post-emergence treatment (tillering stage) .
But the herbicidal effectivenesses of some herbicides by late post-emergence treatment to annual bluegrass were decreased or greatly delayed under low temperatures.
In Kentucky bluegrass and bentgrass turfs terbutol, chlorthaldimethyl, benefin, pendimethalin and acephenone were very useful for its control.
When asulam was combined with either simazine, atrazine or mefluidide, the effectivenesses were additive or synergistic for matured annual bluegrass. When atrazine was combined with either simazine, asulam, napropamide, chlorpthalim, mefluidide, MCPP or trichlopyr, the effectivenesses were the same.

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The downward movements of 19 herbicides caused by rainfall in the soils were studied and the following results were obtained.
Most of the herbicides moved further down in sandy soils than in clayish and organic soils. Most of the herbicides, however, moved a little in sandy soils which were added by top dressingsoil or thatch.
The movements of herbicides in soils were classfied into the following 4 types.
1. The herbicides which were moved to a depth of 0-1.5 cm in soils were; simazine, terbutol, propyzamide. chlorphthalim, pendimethalin, acephenon and siduron.
2. The herbicides which were moved to a depth of 0-3 cm in soils were; orthobencarb, chlorthaldimethyl, atrazine, napropamid and lenacil.
3. The herbicides which were moved to a depth of 0-5 cm in soils were; 2, 4-D, MCPP and triclopyr.
4. The herbicides which were moved to a depth of 0-7 cm in soils were; asulam and bensulide.

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[in Japanese]

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