• Weed & Turfgrass Science
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• v.2 no.2
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• pp.138-151
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• 2013

This study was carried out to investigate the distribution and habitat types of prickly lettuce, Lactuca scariola of Europe origin for supplying the basic data of management plan. It showed fairly nation-wide distribution although excessive growth was rather limited in the wild. Its habitat types were divided into four types like open fields, roadsides, seashores and riversides. Species diversity examined by species rank-dominance curve tended to increase over riverside > seashores > open fields > roadsides. As a result of analyzing life form, therophytes were more than 50%, means that the habitats of L. scariola were disturbed by human activities etc. Urbanization Index was analyzed 9.1% in roadsides, 7.4% in seashores, 5.8% in open fields and riversides. It has high spread potential with a large number of wind-flying seed per plant. It was evaluated that prickly lettuce was mainly spread along the newly constructed road, expressway and invaded the original ecosystem in the cultivated land as weeds. But it has played a role as a pioneer species in open fields. It is recommended to remove where it has considerable impact on the native plant species of conservation value.

• Korean Journal of Weed Science
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• v.18 no.2
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• pp.128-135
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• 1998

The experiment was carried out to obtain basic informations on sod culture using water foxtail in apple orchard at Kyeongbuk Provincial RDA in 1996 to 1997. Period of seedling emergence varied with sowing time and accumulative temperature. Sowing at Nov. 25 required longer than 100 days, while it needed only 8 days when water foxtail was sowed at Sep. 20. In a view of accumulative temperature, sowing at March 15 needed $139^{\circ}C$ but it required about $1,000^{\circ}C$ at August 10. This result showed that the seed of water foxtail has strong summer-dormancy in natural condition. Water foxtail had s-shape growth curve during growing season, and growth rate was the highest from March to May in this period. Plant height increased 2 times and 4 times for dry weight from March 20 to April 20. However, growth was decreased by summer depression after May. Major weeds in apple orchard were horseweed, akino-nogeshi and shepherd's-purse. These species were suppressed by the dominance of water foxtail. Water foxtail as a cover plant could be used for a method of weed control instead of herbicide in apple orchard.

• Korean Journal of Weed Science
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• v.16 no.4
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• pp.264-281
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• 1996

As a consequence of wide use of herbicides, Eleocharis kuroguwai Ohwi became a dorminant problem weed for rice cultivation in Korea. To understand the establishment of the weed, experiments on physio-ecological characteristics were carried out sprouting and occurrence, the results could be summarized as follows: Sprouting percentage remained 68 to 73% until the time of field emergence, indicating many of the them are still dormant. The proportion of the dormant tubers were greater for the smaller than the bigger tubers. Apical dominance was apparent in sprouting, with 84% of tuber sprouted from only one of the apical buds. Tubers sprouted from 2 or 3 buds were less than 20%, and were mostly from the bigger tubers. When the shoot growth was compared, by controlling the others, ones from apical and the next 3 buds showed similar vigorous growth, but the later ones showed poorer growth. For the longevity of tubers, deep soil storage appeared to be better than storage in temperature controlled room to 2~$3^{\circ}C$. Emergence of E. kuroguwai was better in clay soil than in sand, and the possible depth for emergence in clay soil appeared to be up to 21cm, but was 15cm in sand. When tubers were exposed to salt solutions before emergence tests, E. kuroguwai appeared to be much sensitive to salts than S.planiculmis. Among the tubers formed in previous year, 12.7% remained still viable until the end of next crop season, but with relatively strong dormancy. The first emergence was about 10 days after planting at ordinary cropping seasons, and the days to the maximum shoot number stage were 60~90 from planting. The duration was extended at early transplanting, and shoot number, leaves per shoot, and tubers developed per plant were also greater at early plantings. The 6th order offshoots were developing when E. kuroguwai was planted at early season. When planted at later seasons, generation and the number of offshoots was reduced planted at early season. When planted at later seasons, generation and the number of offshoots was reduced and the number of tubers, runner and rhizome lengths was also reduced.

• Korean Journal of Environmental Agriculture
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• v.22 no.1
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• pp.53-59
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• 2003

The present study was conducted to analyze the vegetational difference in fellowed fields at the different seral stages. Plant species were surveyed on the fields having different cropping history, soil moisture conditions, and the duration of set-aside. Effects of soil moisture condition and fellowing duration on the vegetational profiles of fellowed fields in the course of different seral stages. In the fields fellowed for more than three years, a conspicuous feature of vegetation was the dominance of perennial species, which was less dominant in the fields fellowed for less than 3 years. The floristic composition of fellowed fields was dependent on the soil moisture condition. However, the influence of fallow-history on vegetational composition was less than that of the soil moisture conditions. The dominant species occurred in fellowed upland (dry) fields were changed from Glycine soja, Persicaria thunbergiana, and Artemisia princeps at 2-year-fellowed to Persicaria thunbergiana, Miscanthus sinensis, and Glycine soja at 6-year-fellowed. In wet fellowed paddy fields, annual Mosla punctulata, Ambrosia artemisiifolia, and Setaria viridis, the dominant species at 3-year-fellowed, were substituted by perennial Miscanthus sinensis, Aster pilosus, and Hemarthria sibirica at 7-year-fellowed. When the succession continued for 11 years in wet fields, the vegetation was characterized by the domination of perennials such as Phragmites communis, Zizania latifolia, and Typha orientalis. It was suggested that the soil moisture condition was a strong determinant of the dominant species on early seral conditions. In the fellowed paddy fields, the species diversity was relatively higher in the fields set-asided as wet condition compared to the fields fellowed as dry condition.

• Journal of The Korean Society of Grassland and Forage Science
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• v.6 no.2
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• pp.71-77
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• 1986

The field experiment was conducted to evaluate the effect of herbicide treatment (Banvel: 100, 200, U-46: 150, 300, Hedonal: 150, 300, Simazin: 100, 200g/10 a) on change in the botanical composition and dry matter productivity of ladino clover (Trifolium repens L.) dominated pasture mixtures. The experiment was laid down as a randomized block design with 4 replications at experimental field of Livestock Experiment Station in Suweon from 1983 to 1985. The results obtained are summarized as follows: 1. Against ladino clover in mixie grass-clover swards Banvel, U-46 and Hedonal gave good control. The percentage of ladino clover under herbicide tratment decreased to about 1-2%(Banvel), 11-18%(U-46) and 22-31%(Hedonal), respectively, while it increased to 71% in untreated pastures. However, in the second year this trend stated to reverse and occurred clover dominance again in U-46 and Hedonal application, while those remained approximately constant until end of the years under Banvel treatment. Simazin is to be not recommended. 2. The best time for herbicide treatment was found to be late summer before autumn sown 20-25 days. When it applied in early summer weed infestigation by Digitaria spp., Echinochloa spp. and other species was a severe problem. 3. Emergence and early development of introduced pastures were less satisfactory, if it oversown immediatley after herbicide treatments due to its phytotoxical damage. Residual chemicals remained about 7-10 days in topsoils. Perennial ryegrass and orchardgrass were slightly less tolerant than the other species. 4. In dry matter, taken as average of three year results, Banvel applied pastures produced the remarkably high yield of 1023 kg/10 a, which is as much as 44% higher than that of untreated plot. Dry matter yields under U-46 and Hedonal treatment were 842 and 811 kg/10 a, respectively. 5. Weender components and net energy concentration were affected by change in the botanical composition. Crude protein and NEL value were slightly higher in clover dominance than those in herbicide treatments. Total yields of net energy lactation, however, were the highest in Banvel application with 5401 MJ and the lowest in untreatment with 3889 MJ-NEL/10 a DM.

• Korean Journal of Weed Science
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• v.32 no.1
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• pp.1-9
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• 2012

This study was conducted to survey vegetation changes and soil characteristics in Saemangeum new reclaimed tidal land. Soil salinity in border area to tidal land was 22.3 dS $m^{-1}$ but showed 1.1~3.44 dS $m^{-1}$ over the distance of 2 km from border line. The vascular plants in survey sites were recorded as total 26 taxa in 6 families. The frequency of species appearance of Aster tripolium, A. subulatus var. sandwicensis were highest by 61.5 and that of Phragmites communis, Puccinellia nipponica were 53.8. The almost vegetations occurred in the patch which range of soil salinity 14 dS $m^{-1}$ were halophytes as Salicornia europaea, Suaeda asparagoides, S. japonica. As lowed soil salinity as 6.7 dS $m^{-1}$, mixed vegetation of halophytes with P. communis, P. nipponica, Carex pumila were occurred. Dominant species in the range of 3.0 dS $m^{-1}$ area were A. subulatus var. sandwicensis, P. communis, Echinochloa spp., Zoysia sinica and Conyza canadensis. Biomass production was the highest in the area of dominant vegetation with P. communis, and mixed zone with P. communis and Aeschynomene indica are followed. The correlation between vegetation biomass and soil salinity, soil pH and dominance index of vegetation were negative. But that of vegetation biomass and soil organic content were positive.