• Weed & Turfgrass Science
• /
• v.6 no.1
• /
• pp.61-66
• /
• 2017

The appropriate level of irrigation for turfgrasses is vital to the performance of the turfgrass as well as conservation of water. Linear gradient irrigation system (LGIS) facilitates long-term study of turf performance under continuous irrigation gradients at extreme ends of the irrigation scale. The objectives of this study were to: a) determine the minimum irrigation requirements and relative drought resistance in three warm season turfgrasses; and b) evaluate the medium to long-term effects of irrigation levels on turf persistence, weed invasion, and susceptibility to diseases. Results suggest that grasses differed in drought resistance and persistence under variable irrigation regimes. Irrigation (Ep) required for consistent acceptable turf quality for respective grasses was Cynodon dactylon x C. transvaalensis (61%), Zoysia matrella L. Merr (73%), and Stenotaphrum secundatum 'Palmetto' (86%). Brown patch infection was most prevalent in Stenotaphrum secundatum 'Palmetto' at 12 and 125% Ep irrigation. Cynodon dactylon x C. transvaalensis and Zoysia matrella L. Merr were better able to adapt to the various irrigation regimes, and this ability allowed these species to resist drought, and maintain turf coverage which in turn, kept weeds and the occurrence of diseases at bay. Ranking these grasses for their drought tolerance abilities showed that Cynodon dactylon x C. transvaalensis had the most outstanding resistance against drought, followed by Zoysia matrella L. Merr, and lastly, Stenotaphrum secundatum 'Palmetto'. Despite having the highest irrigation requirement, Stenotaphrum secundatum 'Palmetto' was still not able to maintain persistence at high irrigation regimes. Likewise, this grass also lost turf coverage at low irrigation levels.

• Asian Journal of Turfgrass Science
• /
• v.15 no.2
• /
• pp.51-64
• /
• 2001

Summer stress is one of the serious problems on cool-season grass at the soccer fields in Korea during heavy rainy season. This study was conducted to intestigate the effect of shade net with regard to its percent (0, 50, 75), color (black, green), height (0 cm, 30 cm) and time (7 hr, 24 hr) on turf canopy temperature, light intensity, leaf color, turf performance, clipping yield and root dry weight of cool-season turfgrass. Turf canopy temperature was 6~13$^{\circ}C$ under black and green shade net when temperature was over 4$0^{\circ}C$. Light intensity was also decreased from 40 to 94% under black and green shade net compared to control. Black shade net was more effective than green net in reduction of temperature and light intensity. Green shade net was found to be better for photosynthesis of cool-season grass. Leaf color, turf performance, clipping yield, and root dry weight were better and increased under 50% and 75% shade net. 50% black shade net with 30cm height and 7 hr treatment showed the best turf performance. It can be concluded that 50% and 75% green shade net can be used fur reducing summer stress on cool-season grass after soccer marches during heavy rain season. The shade net decreased the turf canopy temperature and reduced heating damage of cool-season turfgrass.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.20 no.1
• /
• pp.53-68
• /
• 1992

This study was carried out to estimate the recreation carrying capacity of lawn areas in parks. Recreation carrying capacity in this study is composed of two parts, ecological carrying capacity and psychological carrying capacity. As the first part, this paper deals with the treading times criteria based on the tolerence of the turf to treading pressure. The plant material used for this study was Zoysia japonica, and the treading experiment was done in the experimental fields in Kyungju and Suwon, Korea. The major results of the first part of the study are summarized as follow: 1. As shown in annual change of the growth of the turf, The growth of turt grass was represented by the number of leaf. 2. The tolerance to treading was not significantly different by the time of treading treatment. And the tolerance varies depending on growth rate of grasses, which showed significant relationship with precipitations. 3. From the result of different numbers of simulated treading treatment, the damage of the turf was increased by the increase of the frequency of treading. And the damage was very serious within short period(about 20 days) in high frequency(over 20 times/day) of treading treatment. But low frequency(1∼3times/day) of treading shows good effects on the growth of the turf. 4. The criteria of treading number per day for each carrying capacity level are estimated as 7 times/day for optimum carrying capacity, 13 times/day for standard carrying capacity, and 20 times/day for critical carrying capacity.

• Asian Journal of Turfgrass Science
• /
• v.18 no.3
• /
• pp.119-128
• /
• 2004

This study was conducted to analyze the effect of roof membrane on light environment that influence on turfgrass growth under domed stadium. Roof structure on experimental plot was constructed with PTFE and PE same as Busan Asiad Main Stadium. Tested turfgrass species were combinations of cool-season grasses(Kentucky Bluegrass, perennial ryegrass, $KBG80+PR20\%,\;KBG33+PR33+Fine fescue33\%)$ and warm-season grasses(zoysiagrass, 'An-yang middle-leaf, 'Zenith', Bermudagrass) established with seeding or sodding. The experimental set-up and research work were initiated November 1999 and finished on August 2000 at near Busan Asiad Main Stadium. By the result of computer simulation of daylight radiant energies on the turf surface were lower than needs of normal sport turf growth. The shortage of radiant resulted pest infection on cool-season grass mixture compared with warm-season. But turf color and density showed the best results on Kentucky bluegrass or its mixture plot. Over all the results showed that the best quality of turfgrass growth was occurred on full sun area, and the next was under PTFE membrane. The application of artificial lighting system may increase the turfgrass growth under domed stadium(partially) covered with roof membrane.

• Asian Journal of Turfgrass Science
• /
• v.25 no.2
• /
• pp.153-159
• /
• 2011

This study was carried out to know the insect fauna of turf grass area in forest. In Korea, graves and public cemetery in mountain areas are usually covered by turf grass which were mainly examined. There were 86 species belonging to 77 genera of 39 families in 11 orders. Among them, site 3 had highest occurrence (38%), second was site 2 (36%) and in the last place was site 1 (26%). Hemiptera revealed best species composition (29.1%) and came Coleoptera (19.8%), Orthoptera (15.1%), Lepidoptera (12.8%) and Odonata (5.8%) etc. The reason why Hemiptera and Orthoptera are mainly found in these areas is because they usually feed on short plants that grow in there. Taxonomic species composition, occurrence ratio by site and species and comparison analysis were provided.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.21 no.4
• /
• pp.233-246
• /
• 2001

The purpose of this study was to suggest the possibility of utilizing the wildflower pasture for promoting public interest. Growth characteristics, botanical composition, fauna distribution on wildflower pastures were observed. The experimental design included two treatments: native wildflower pasture(NWP, turf grasses 6 species + native wildflower 11 species) and introduced wildflower pasture(lWP, turf grasses 6 species + introduced wildflower 9 species). The field trials were carried out on the experimental pasture plots at Chungnam National University from 1997 to 2000. The results obtained are as follows: 1. The flowering of wildflower was maintained continuously from May to September, and the colors of wildflowers; varied seasonally during this period. With native flowers, however, Hemerocallis fulva, Belamcanda chinenis and Aster koraiensisi showed problems in lately germination and early establishment. Meanwhile, Introduced wildflower showed not only excellent germination and early establishment compared to native flowers species but also maintained brighter colors. But Coreopsis tinctoria, Achillea mi/lefolium and Rudbeckia bicolor had colonized at a higher height or possessed stronger rhizome. 2. The appropriate species of turf grass which maintained continuous seasonal distribution are thought to be tall fescue, perennial ryegrass. Kentucky bluegrass in NWP and IWP. 3. Botanical composition of wild flower in NWP was arranged in the order of Achillea sibirica > Lotus corniculatus var. Japonicus > Dianthus chinensis > Plantago asiatica > Taraxacum pla~ycarpum > Viola mandshurica > Aster koraiensis > Vicia tetasperma > Lespedeza stipulacea > Hemerocallis fulva, respectively. The highest seasonal distribution of native wildflower, Achillea sibirica was in spring and summer, Lotus corniculatus var. Japonicus was in autumn. Botanical composition of wild flower in IWP was arranged in the order of Achillea millefolium Coreopsis tinctoria > Silene armeria > Coreopsis lanceolata > Rudbeckia bicolor > Sanguisorba oficinalis > Centaurea cyanus > Chrysanthemum leucanthemum > Dianthus petraeus, respectively. The highest seasonal distribution of introduced wildflower, Silene armeria was in spring, Achillea millefolium was in summer, and Coreopsis tinctoria was in autumn.

• The Plant Pathology Journal
• /
• v.21 no.4
• /
• pp.328-333
• /
• 2005

Paenibacillus elgii SD17 (KCTC $10016BP^T$=NBRC $100335^T$) was recently reported as a new species. Based on its inhibitory activity to Thanatephorus cucumeris AG1-1, strain SD17 was further evaluated for its potential as a biocontrol agent against soil-borne diseases of turf grasses in Korea. P. elgii SD17 showed a broad spectrum of antimicrobial activity in vitro test and suppressed development of turf grass diseases; Pythium blight caused by Pythium aphanidermatum and brown patch caused by T. cucumeris AG1-1 on creeping bentgrass (Agrostis palustris) in the growth chamber tests. Under a condition for massive culture in a 5,000 L fermenter, P. elgii SD17 reached $6.4{\times}10^8$ spores/ml that resulted in approximately $1.0{\times}10^7$ cfu/g when formulated into a granule formulation (GR) using the whole culture broth instead of water. Using the GR formulation, biocontrol activity of P. elgii SD17 was confirmed. In the growth chamber tests, the GR formulation was effective against brown patch and Pythium blight with similar level of disease severity compared to each of the standard fungicides at the application rates of 10 g/$m^2$ or above. In the field tests, compared to each untreated control, the GR formulation also effectively controlled Pythium blight, brown patch and large patch at all the application rates of 5, 10 and 20 g/$m^2$, respectively, without significant response by the application rates. However its performance was inferior to each of the standard chemical fungicides. Based on these results, we consider this GR formulation of P. elgii SD17 as an effective biocontol agent to suppress Pythium blight, brown patch and large patch of turf grasses in Korea.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.34 no.6 s.119
• /
• pp.39-53
• /
• 2007

Unlike conventional roof landscaping, where various kinds of plants and structures are employed, a grass roof is a roof on which herbaceous plants are grown in planting medium and which is not accessed or maintained, mainly because it doesn't have sufficient load capacity to support a regular roof garden. They are mostly built on existing roofs, whether flat slab or gabled. Planting on roofs has numerous advantages, such as creating a biotope, purifying urban air, adding moisture to the atmosphere, storing rain water, preventing flash floods, reducing energy use for heating and air conditioning, enhancing the urban landscape and providing relaxation to the city dwellers, not to mention the alleviation of global warming by absorbing $CO_2$. In addition to the general merits of roof planting, the grass roof has its own unique qualities. Only herbaceous species are planted on the roof, resulting in light weight which allows roofs of existing buildings to be planted without structural reinforcement. The species chosen are mostly short, tough perennials that don't need to be maintained. These conditions provide an ideal situation where massive planting can be done in urban areas where roofs are often the only and definitely the largest space available to be planted. If roofs are planted on a massive scale they can play a significant role in alleviating global warming, heat island effects and energy shortages. Despite the advantages of grass roofs, there are some problems. The most significant problem is the invasion of neighboring plants. They may be brought in with the planting medium, by birds or by wind. These plants have little aesthetic value comparing to the chosen species and are usually taller. Eventually they dominate and prevail over the original species. The intended planting design disappears and the roof comes to look wild. Since the primary value of a grass roof is ecological, a change in attitude towards what constitutes beauty on the roofscape is necessary. Instead of keeping the roof neat through constant maintenance, people must learn that the wild grass with bird's nests on their roof is more beautiful as it is.

• Weed & Turfgrass Science
• /
• v.4 no.1
• /
• pp.71-75
• /
• 2015

Playground is frequently used for physical and sports activity by students as well as by common people, which is constructed with various cover materials on the ground. This research surveyed the surface temperature in Kyungpook National University Sangju campus playground which is covered with various cover materials [bare field, zoysiagrass (Zoysia japonica) turf field, urethane track, concrete field, epoxy field and artificial turf field] in Sangju, Gyeongsangbukdo, Korea. Temperature was measured 4 times per day at 09:00, 12:00, 15:00, and 18:00 from May to October 2014 in surface and 1 m height above the ground. Surface temperature was different, depending on cover materials and survey time. Bare field and zoysiagrass turf field was lower surface temperature than other sites. Higher surface temperature site was different depending on survey time. Urethane track and artificial turf field was hotter than other sites at 12 and 15 hours, however concrete and epoxy field was hot at 18 hours. One meter above ground temperature was the highest in artificial turf field except at 18 hours. So natural turf, zoysiagrass playground will increase the athletic performance by reduce the surface and above ground temperature.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.27 no.3
• /
• pp.173-182
• /
• 2007

The purpose of this study was to compared the early growth pattern, stem, leaf and root weight, DM yield, flowering characteristics and preference for selection of turf type grasses and wild flower species in mixtures combination for wildflower pasture. The experimental design included five species of turf grasses and 11 species of wildflower : turf type grass species{Kentucky bluegrass(Midnight), tall fescue(Millennium), perennial ryegrass(Palmer III), redtop(Barricuda) and creeping bentgrass(Crenshaw)}, wildflower species {Chrysanthemum leucanthemum L. Coreopsis lanceolata L., Rudbeckia bicolor Nutt.., Dianthus chinensis L., Chrysanthemum lindicum L., Lotus corniculatus var. Japonicus Regel, Veronica linariaefolia Pallas, Aster koraiensis Nakai., Chrysanthemum zanadskii var. latilobum (Maxim.) Kitamura, Lythrum anceps Makino and Iris pallassi var. chinensis Lodd}. The field trials were carried out on the experimental pasture plots of Chungnam National University from January 2005 to December 2006. The appropriate species of turf grass which have a mixture possibility with wildflower are thought to be Kentucky bluegrass. Compared with Kentucky bluegrass, on the other hand, species such as Chrysanthemum leucanthemum L., Lotus corniculatus var. Japonicus Regel, Chrysanthemum zanadskii var. latilobum Maxim.) Kitamura and Lythrum anceps Makino have shown advantageous aspects of fast early growth pattern and highly weights of stem, leaf and root. Futhermore, these wild flowers were in harmony and no overlap on flower color, flowering periods and flowering longevity, and highly preference by Korean native goats. For the establishment of wildflower pasture in Korea, therefore, it is important to select the appropriate species of turf glasses, which have a weak competition against wild flowers, and then to make mixture combination of those turf glasses with the various wild flowers which have a strong competition against turf glasses but have a different anthesis characteristics among themselves.