• Asian Journal of Turfgrass Science
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• v.19 no.1
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• pp.1-16
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• 2005

This study was conducted to effect a complex fertilizer treatment on a recovery of damaged turfgrass caused by competing with tree at area under trees, and to seek for effective management system on damaged areas under trees in golf courses. Available phosphorous and potassium were enough to grow up turfgrass in plots of East valley and Ji San Golf Club. But these plots were acid soil ranged from pH 5.3 to pH 5.5, so that lime fertilizer was required for improving the chemical of soil. The effect on complex fertilizer showed significant f3r the recovery of damaged turfgrass. Turfgrass recovery ratio by complex fertilizer was better in low-density(LD) section of fertilizer than in high-density(HD) section of control. As the result of surveying turfgrass characters according to dates, dry matters in HD sections of control plots were higher than these in LD sections of fertilizer plots in 6 Aug. before sprinkling a complex fertilizer. But dry matters in LD section of fertilizer were, on the contrary, higher than in 6 Sep. after sprinkling complex fertilizer. In view of the result so far conducted, a turfgrass recovery to LD sections of complex fertilizer was batter than that of HD sections of control. Sprinkling complex fertilizer on turfgrass damaged by competing with trees will maintain the turfgrass growth, even though happen to compete between trees and turfgrass.

• Asian Journal of Turfgrass Science
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• v.20 no.1
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• pp.25-31
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• 2006

'Meyer' zoysiagrass(Zoysia japonica Steud.) is a popular turfgrass species used for transition zone golf course fairways and tees in mfd U.S.A golf courses because it is generally winter hardy while providing an excellent playing surface with minimal chemical and irrigation inputs. However, its functionality declines easily in many of the shaded areas of these courses. Reduced irradiance causes excessive shoot elongation, reduced tillering, and weak plants that are poorly suited to tolerate or recover from traffic and devoting. Trinexapac-ethyl (TE) effectively reduces gibberellic acid (GA) biosynthesis and subsequent shoot cell elongation. This study was initiated to evaluate TE effect on shoot elongation and stand persistence under two levels of shade in 'Meyer' zoysiagrass. A mature stand of 'Meyer' was treated with all combinations of three levels of shade(0%, 79%, and 92%) and three levels of monthly TE [0, 48 $g{\cdot}ha^{-1}$ a.i(0.5x) and 96 $g{\cdot}ha^{-1}$ a.i(1x)]. In full sun, the TE at 48 $g{\cdot}ha^{-1}$ a.i reduced clipping yield by 18% over a four-week period and, whereas the TE at 96 $g{\cdot}ha^{-1}$ a.i by 30% to 38%. Monthly application of TE at the 96 $g{\cdot}ha^{-1}$ a.i increased 'Meyer' tiller density in full sun and under 79% shade. Both rates of TE consistently reduced shoot growth under shade relative to the shaded control. Only the monthly applications of the TE at 96 $g{\cdot}ha^{-1}$ a.i consistently delayed loss of quality under 79% shade. Our results indicate TE can be an effective management practice to increase 'Meyer' zoysiagrass persistence in shaded environments.

• Asian Journal of Turfgrass Science
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• v.23 no.2
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• pp.279-286
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• 2009

This study was carried out to utilize the waste heat from office building for turfgrass culture on a roof garden. Heating system had been installed in the middle of soil profile on the turf areas in the garden plots. The results showed that the installation of heating system increased the shoot density, turfgrass quality, coverage rate, and root length compared with the control plots. The surface temperature of heating plots reached at $10.9^{\circ}C$ when the control plot showed $0^{\circ}C$, however, the soil moisture content was decreased 1.9% by the heating system. When the height of the snow accumulation reached over a 15cm, the it took only 4 days to melt out completely, while the height did not changed those period at the control plots. When the water temperature in boiler increased to $60^{\circ}C$ from a proper temperature of $55^{\circ}C$ in turf growth, the desiccation from leaf tip was started to occur caused by drought stress. More detail research should be followed in stress physiology in turf management in roof garden operation.

• Asian Journal of Turfgrass Science
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• v.6 no.2
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• pp.89-98
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• 1992

Cultural characteristics and pathogenicity on the isolates of Rhizoctonia oryzae, R. oryzae-sativae and anastomosis group of R. solani and evaluation of selected fungicides on brown patch disease of creeping bentgrass and large patch disease of zoysia grass were studied comparatively. From effect of temperature on the rate of mycelia growth, the result indicated that the temperature groups were separated into four types : isolates of R. oryzae and R. oryzae-sativae had an optimum temperature of $30~35^{\circ}C$. Anastomosis groups of R. solani were separated into three temperature types as followings : high temperature type had an optimum temperature from 25 to $30^{\circ}C$, moderate type had grown from 20 to $25^{\circ}C$ for optimum and low temperature type had an optimum temperature of $20^{\circ}C$ but at $35^{\circ}C$ did not grow. Inoculation tests showed that AG-1( I A), AG-1( I B), bentgrass isolate of R. solani and R. oryzae were strongly pathogenic on creeping bentgrass, followed by AG-2-1, AG-4, AG-5 and AG-2-2 isolates of R. solani moderately to weakly. Zoysia grass isolate of R. solani and R. oryzae were strongly pathogenic on zoysia grass but AG-1( I B) and AG-5 isolates of R. solani showed moderately pathogenic. Capro(iprodione oxine-copper) and mytan(myclobutanil) were extremely effective against brown patch disease of creeping bentgrass and large patch disease of zoysia grass followed by thiopan (thiopanate-methyl) and pencycuron for brown patch disease and tolos(tolclofos-methyl) and thiopan for large patch disease.

• Weed & Turfgrass Science
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• v.2 no.1
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• pp.55-61
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• 2013

This study was carried out to investigate the morphological and soil characteristics of Zoysia spp. native to South Korea. Samples [41 ecotypes of Zoysia japonica, 28 ecotypes of natural hybride between Z. japonica and Z. sinica (Junggi), 22 ecotypes of Z. sinica, and 8 ecotypes of Z. matrella] were collected in seashores, levee and summit of the rock in southern Korea. Variations in leaf width, plant height, leaf angle, length of leaf sheath, leaf trichome, stolon length, and seed shape were measured at collection sites and experimental plots. Among the entries, most of the measurements did not show any significant differences between natural and experimental plot except for leaf angle of Z. sinica and the number of seeds per spike of Z. matrella, which might be caused by different environmental conditions. Soil pH was 6.0 at the most of the collection sites. $Mg^+$ was 0.06-0.02 $cmol{_c}^+kg^{-1}$, $Mg^{2+}$ was 0.09-0.03 $cmol{_c}^+kg^{-1}$, and $K^+$ was 0.02-0.007 $cmol{_c}^+kg^{-1}$ at most zoysiagrasses growing soils.

• Journal of the Korea Organic Resources Recycling Association
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• v.22 no.4
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• pp.11-20
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• 2014

Recently, manure emissions associated with the numerical increment of the domestic hog-breeding have increased, but it has been banned from ocean dumping by the United Nations Convention in 2012. To find out the site for spraying in large quantity of liquid manure fertilizer, we selected one grass plantation, which has the largest amount of grass production, in Jangsung, South Korea. We spread not only chemical fertilizer but also liquid manure fertilizer on the zoysiagrass plantation and researched the effect on the grass growth and development, soil chemical property, and seepage water of dike. As the test results, spread by compounding chemical fertilizer and liquid manure fertilizer and it is possible to substitute for some chemical fertilizer in terms of nutrients accumulation and the grass growth and development. Additionally, it gives less effects to soil chemical property and is efficacious to effective microorganism growth of soil. Therefore, adding liquid manure fertilizer will lead to reduce almost all the amount of chemical fertilizer usage. It is also expected to help for livestock manure management and to influence reducing the production cost of the grass plantation. However, to spread liquid manure fertilizer contaminates water system. For this reason, monitoring continuously, we need to find out improvement plans of the fertilization method in order to increase the usage of liquid manure fertilizer.

• Asian Journal of Turfgrass Science
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• v.17 no.2_3
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• pp.75-80
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• 2003

Growth characteristics such as density(quality), covering speed, green period, disease resistance, heading existence(number of seeds) and other characteristics were examined for selection of superior lines among the 133 zoysiagrass lines collected in 2001. Six superior lines were selected and the results were summarized as follows. Superior line, J01067 was longest for green period among the 133 zoysiagrasses and stayed green until the beginning of November. Leaf width of J01106 and J01129 lines was very narrow as 1.5mm and 2mm, respectively and superior for density(quality), covering speed and disease resistance. J01122 line was selected for strongest disease resistance among the lines of Zoysia japonica. Leaf width of J01128 was 3.2mm showing midium type and similar to standard cultivar, Sunburst. This line also showed higher density and strong disease resistance like J01106 and J01129. Five growth characteristics for morphological classification of 133 zoysiagrass lines was used and divided into 3 cluster groups. Of 133 lines, 6 standard cultivars and 6 superior lines were classified as follows. First cluster group contained Belare, Meyer, Anyang-jungji, J01067, J01122, and second group contained S-94 and J01105, and third group contained Sunburst, Konhee, J01106, J01128 and J01129.

• Asian Journal of Turfgrass Science
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• v.23 no.2
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• pp.287-294
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• 2009

This study conducted to evaluate the growth characteristics of creeping bentgrass in summer after application of the plant growth regulator, Trinecapac-ethyl, and these data may provide basic information to golf course turf maintenance. The results showed that the shoot density of creeping bentgrass was increased an average density of 1.7 $ea/cm^2$ with the trinexapac-ethyl application, especially about 2 $ea/cm^2$ during the growth retarded period of June and July. The root length increased also in June and August. The visual quality was improved significantly with trinexapac-ethyl treatment all the experimental periods, moreover, the effect was significant by reducing a summer decline stress of creeping bentgrass during the warm and humid period of summer. The green speed was significantly improved by this growth regulator treatment and those effect was prominent during stressed season of late June to mid July. Overall of the result, we found that shoot density, visual quality and green speed of bentgrass green were improved by trinexapac-ethyl treated from early growing season of spring and these effects were continued during summer. It should be very beneficial to manage the bentgrass green in stressed season. In future, the possibility and efficiency of mixture with fungicides and/or fertilizers might be needed. The spring green-up test with trinexapac-ethyl will be followed in next spring.

• Asian Journal of Turfgrass Science
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• v.8 no.3
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• pp.193-199
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• 1994

Effect pf rape seed oil cake compast (OM) active carbon(C) compound fertilizer (NPK) and magnesium sulfate (Mg) application on Zoysia koreana growth by lysimeter of 50cm soil column filled with a low fertility loam. Effect on growth was in order of OM>OM . NPK interaction> NPK . active carbon and Mg were not effective OM . NPK interaction effect was negative on leaf width and root dry matter yield. OM and OM . NPK interaction were most effective on rhizome growth. Their effect did not change the ratio of growth rates between aerial part and rhizome but change that between aerial part and root. Leaf width was most sensitive to the treatments.

• Weed & Turfgrass Science
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• v.7 no.2
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• pp.148-157
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• 2018

Research was initiated to evaluate four domestic and overseas organic soil amendments (SAs) on turfgrass groundcover and density and to provide basic information on practical sports turf establishment. This study was conducted in Agrostis palustris Huds. (CB) grown in sand-based root zone. A total of 20 treatments of SA+sand were prepared by mixing 10 to 50% (v/v). These amendments were SABP (Berger Peat), SAEP (Eco-Peat), SAGS (G1-Soil), and SAPP (Premier Peat). Turfgrass groundcover and density significantly varied with SAs, its mixing rate to sand and week after seeding (WAS). Cumulative turfgrass density was variable, but a great change occurred between 2 and 4 WAS. Turfgrass density at 2 WAS ranged from 36.7 (SABP 30) to 89.7% (SAGS 20), being 53.0% in differences among treatments. However, CB reached to carrying capacity around 6 WAS. Thus, most treatments were similar to 90% or so in density. At the end of study, overall groundcover ranged between 60.7 (SAEP 10) and 96.7% (SAPP 50). Proper mixing rate was variable with SAs, being 10 and 20% for SABP and SAGS, respectively. But the optimum rate was 50% for both SAEP and SAPP.