• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.302-302
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• 2017

This study was conducted to evaluated the effects of different sowing time(October 22, February 20, March 3, March 13, and March 23) and sowing quantities(150kg/ha, 200kg/ha, 250kg/ha, and 300kg/ha) on growth of naked oat(Avena sativa L.) cultivar(Choyang-Gwiri) at a cultivation area in Iksan, south Korea. Heading times were delayed with later sowing times. In autumn seeding(Oct. 22) the ear was headed at April 30, in spring seeding(Feb. 20, Mar. 3, Mar. 13, and Mar. 23) heading times were respectively May 14, May 14, May 15, and May 19. Heading time of spring seeding was delayed about 3 weeks than autumn seeding. Ripening times were similar trends to the heading times. In autumn seeding ears were ripened at June 7, in spring seeding each times were respectively Jun. 15, Jun. 13, Jun. 20, and Jun. 20. Ripening time of spring seeding was delayed about 2 weeks than autumn seeding. Culm length and ear length were shortened in spring seeding, but number of plants per $m^2$ were increased. Number of grains per a ear were 106 in autumn seeding, but grains per a ear in spring seeding were respectively 88, 83, 83, and 73. Weight of 1,000 grains in spring seeding was heavier than that in autumn seeding, the weights were tend to light as later seeding times. Yield of grains was declined as later seeding times, yield of in autumn seeding was 2,900kg/ha, whereas that in spring seeding was 2,180kg/ha. The highest yield of spring seeding time was in Mar. 13, before this seeding time soil surfaces were severely dried as few rain fall, so germination was poor in those seeding times. As several seeding quantities were seeding, earing and ripening times were not different. but increasing seeding quantity, culm length was lengthened and ear length was shortened, number of plants per $m^2$ were increased and grains per a ear were reduced. Yield of grains were increased more seeding quantities, yield was highest up to 250kg/ha seeding quantity.

• Journal of Bio-Environment Control
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• v.17 no.1
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• pp.60-65
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• 2008

For autumn field cutting of Sedum sarmentosum, the effects of cutting site (distal, middle, and proximal) and planting method (space drill seeding, drill seeding, and broadcast seeding) on survival rate and growth characteristics were investigated at pre- and post-winter season. Plant height root length, stem number per plant, number of branch per plant, fresh weight of shoot, and dry weight of shoot were significantly superior in distal site at pre-wintering (40 days after cutting). At post-wintering (May 10th), stem number per plant, fresh weight and dry weight per $m^2$ in cutting of distal site showed a significant increasement compared to the cutting of proximal site. At pre-wintering (40 days after cutting), the growth in space drill seeding was well than that in drill seeding and broadcast seeding, and fresh weight and dry weight per $m^2$ in space drill seeding were high in order of space drill seeding, broadcast seeding, and drill seeding. At post-wintering (May 10th), stem number per plant, fresh weight and dry weight per $m^2$ in space drill seeding were significantly increased than those in drill seeding. Accordingly, the cutting using distal site of stem in autumn field cutting was desirable for the growth and shoot yield. The space drill seeding showed the highest yield potential among three seeding methods, but broadcast seeding was favorable in saving of labor, because the fresh weight of shoot in broadcast seeding was similar in the space drill seeding at post-wintering.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.4
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• pp.664-670
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• 2012

Experiments were conducted to find out the landscape effects and green manure production at the same time in farmland. Cornflower was grown in different soil texture with sand, sandy loam, loam, clay loam, and was sowing with autumn and spring respectively. The overwintering rate of cornflower was at 58.7% in average, and the treatment at sand soil showed 62.1% that was highest among other soils, which cornflower is possible to winter landscape crop. After flowering of cornflower, the contents of total nitrogen (T-N) and total carbon (T-C) in plant were 15.0 and $409.2g\;kg^{-1}$, respectively, and the carbon-nitrogen ratio (C/N) was 28.6. The yield of cornflower biomass, which will be returned to soil as green manure, recorded $1,210{\sim}3,920kg\;ha^{-1}$ at the spring seeding higher than the autumn seeding as $1,540{\sim}3,170kg\;ha^{-1}$, and the biomass treated by soil texture were showed that the treatments at the clay loam had been the largest yields both spring and autumn seeding among at other treatment of soil. The heights of cornflower regardless of soil treatments were 52.8 to 73.6 cm at the autumn seeding and 35.5 to 79.2 cm at the spring seeding although it was more significant variation at the soil textures than the seeding periods. The flowering periods of cornflower ranged from $17^{th}$ to $20^{th}$ in May at the autumn seeding and from $19^{th}$ to $20^{th}$ in June at the spring seeding, which was faster 30 days approximately at the autumn seeding than the spring seeding. In a view of the cornflower application as green manure after flowering, the autumn seeding, when considered to combine with following crops, was more suitable and various than the spring seeding, even though the yield at spring seeding was higher than one at autumn seeding.

• Journal of the Korean Institute of Landscape Architecture
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• v.25 no.2
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• pp.62-72
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• 1997

This study was conducted to find out the hydroseeding timing of several herbaceous plants for the slope revegetation works. Four native plants and five introduced grasses were used for this experiment and were seeded on the cut slopes by hands in April, May, June, September and October. To identify the best seeding timing, germination percentage, ground covering rate, number of tillers and plant heights were investigated. There were wide differences in germination and ground covering rates of native plants are lower than those of cool-season foreign grasses and they show different germination rates according to seeding timing. Among them, Arundinella hirta var. ciliata shows the most apparent germinatin pattern according to seeding timing. 2. Seeding timing : Native plants tend to germinate well in May and June and cool-season foreign grasses in May and September. But Native plants show extremely low germination rates in autumn, so it is necessary to adjust the seeding rates when seeding in autumn. When seeding in May, it will be possible to use native plants-seed-mixture without using introduced foreign grasses. In sum, the best seeding timing of cool-season foreign grasses are May and September, and warm-season foreign grass is May and June. The best seeding timing of native plants seem to be in May and June.

• Journal of The Korean Society of Grassland and Forage Science
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• v.2 no.2
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• pp.1-15
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• 1981

In reviewing of the literature concerning agronomic practices on intensive pasture establishment the following suggestions were made : (1) The seedbed preparation should be involved physical manipulation of the soil tilth and consolidation of the soil by harrows and heavy roller. (2) In terms of methods of sowing, drilling favours the first and broadcasting the second however, the apparent superiority of band sowing over the above conventional methods is to reduce the direct toxic chemical effects from fertilizers to germinating seeds. (3) The most satisfactory seeding depth for grasses and legumes is commonly agreed to be approximately 1.3cm and seeding depth greater than 2.5cm seems to be generally detrimental. (4) Autumn and spring are most common sowing periods for grasses and legumes, however, early autumn being the most generally favoured, particularly in areas not subject to severe winter kill. (5) Select nurse crop species or cultivars which make Bess demands on light, nutrients and water, and lower seed rates should be used. (6) Seeding mixtures should be simple rather than complex and aggressive species should be included to a minor extent.

• Journal of The Korean Society of Grassland and Forage Science
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• v.12 no.1
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• pp.67-70
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• 1992

The experiment was conducted to evaluate the effect of the different seeding date on the dry matter yield and chemical composition of oat for forage. The crops wrc sccdcd on August 3l(lirst). Scptember IO(second). and September 20(third seeding date) and were taken on November 24, 1991. The results are summarized as follows : 1. The plant heights were 68, 54 and 40 cm at first, second, and third seeding date, respetively. 2. Dry matter (DM) content decreased with delaying seeding date from first to third seeding date. DM varied from 18.6 to 14.9 %. 3. Leaf weight ratio increased with delaying seeding date from first to third seeding date, varied from 51 to 67 %, but stems decreased from 49 to 33 %. 4. The dry matter yields per ha decreased with delaying seeding date: it was 5.670. 3.960 and 2.310kg at first, second and third seeding date. Significant differences has been obtained among date(P<. 05). 5. The content of crude protein increased with delaying seeding date from first to third seeding date. varied from 16.3 to 22.6%. but NDF and ADF content decreased.

• Korean Journal of Organic Agriculture
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• v.15 no.1
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• pp.59-69
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• 2007

This experiment was conducted to study the spring productivity and feeding value of hairy vetch varieties. We also measured DM yield and feeding value by analyze CP and CF that authors made possible to calculate TDN and RFV. The results can be summarized as follows; Dry matter yield were increased earlier autumn seeding date and later cut in spring. Differences of dry matter yield in earlier cut in spring was high in order of Ostsaat, Welta, Vv4712, Penn-02, Common and Minnie. Crude protein(CP) yield was increased when earlier autumn seeding date and later cut in spring. Total digestible nutrient(TDN) yield of hairy vetch varieties was decreased when later autumn seeding date, and was increased when later cut in spring. TDN yield was highest in Ostsaat and Welta varieties had highest dry matter yield. Acid detergent fiber(ADF) content was decreased when later autumn seeding date and was increased when later cut in spring. Neutral detergent fiber(NDF) content was decreased when later autumn seeding date. Average values for relative feed value(RFV) were 157% and 132% in both cut. It shows that a high feed value in all of hairy vetch varieties. Above all, the results presented that the optimal seeding date for cultivating hairy vetch in the central region of Korea is between the 10th to the 20th of September. Because Ostsaat and Welta had significantly high dry matter yield we expected Ostsaat and Welta have a higher wintering ability.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.6
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• pp.400-404
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• 2000

Hairy vetch (vicia villosa Roth), leguminous green manure crop, can increase soil fertility and reduce chemical nitrogen application for cash crop such as spring corn. More yield of hairy vetch is needed at planting cash crop to obtain higher effect of green manure. Hairy vetch waa seeded on Sep.10, Oct.1, and Oct. 20 and at 10, 20, 30 and 40 kg/ha of seeding rate respectively, in 1996 and 1997, Dry matter and nitrogen yield of hairy vetch were measured on May 1 in 1997 and 1998. Proper seeding rate of hairy vetch was 30 kg/ha irrespective of years and seeding dates. Above-ground dry matters of hairy vetch on May 1 in 1997 and 1998 decreased according to delayed seeding, and those were 5.5-7, 4-4.5, 1.3-2.2 ton/ha on Sep. 10, Oct. 1 and Oct 20 of seeding date, respectively in seeding rate 30-40 kg/ha. Also nitrogen yield of hairy vetch on May 1 decreased according to delayed seeding, and those were 220-280, 160-180, 60-100kg/ha on Sep. 10, Oct. 1 and Oct 20 of seeding date, respectively in seeding rate 30-40kg/ha. Therefore, we suggest that hairy vetch has to be seeded earlier in autumn to obtain high green manure yield in spring. To determine the detailed optimum seeding time in autumn, hairy vetch was seeded on Aug. 20, Aug. 31, Sep. 10, Sep. 20, and Sep. 30 in 1999 and was harvested on April 22, April 27, and May 2 in 2000, respectively. Dry matter and nitrogen yield of hairy vetch by seeding in late August were higher than those by seeding in September indicating that dry matter of hairy vetch were 7-8, 6-7, 4-5, 2-3 ton/ha and nitrogen yield were 240-290, 200-260, 150-220, 70-120 kg/ha, respectively when seeded on Aug. 20, Aug. 31, Sep. 10, Sep. 20 and Sep. 30 and harvested on April 22-May 2. Increase of dry matter and N yield of hairy vetch by 10days delayed harvest was higher in late August seeding than in September seeding. So hairy vetch should be seeded in late August if possible to obtain much more green manure yield and be seeded until September because green manure yield decrease rapidly when seeded after October.

• Journal of Environmental Science International
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• v.30 no.12
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• pp.1027-1039
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• 2021

In this study, we investigated the optimal meteorological conditions for cloud seeding using aircraft over the Korean Peninsula. The weather conditions were analyzed using various data sources such as a weather chart, upper air observation, aircraft observation, and a numerical model for cloud seeding experiments conducted from 2018 to 2019 by the National Institute of Meteorological Sciences, Korea Meteorological Administration. Cloud seeding experiments were performed in the seasons of autumn (37.0%) and winter (40.7%) in the West Sea and Gangwon-do. Silver iodide (70.4%) and calcium chloride (29.6%) were used as cloud seeding materials for the experiments. The cloud seeding experiments used silver iodide in cold clouds. Aircraft observation revealed relatively low temperatures, low liquid water content, and strong wind speeds in clouds with a weak updraft. In warm clouds, the cloud seeding experiments used calcium chloride. Observations included relatively high temperatures, high liquid water content, and weak wind speeds in clouds with a weak updraft. Based upon these results, we determined the comprehensive meteorological conditions for cloud seeding experiments using aircraft over the Korean Peninsula. The understanding of optimal weather conditions for cloud seeding gained from this study provide information critical for performing successful cloud seeding and rain enhancement.

• Journal of the Korean Institute of Landscape Architecture
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• v.25 no.1
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• pp.73-81
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• 1997

This study was conducted to find out the hydroseeding timing of woody plants. Five native plants were used for this experiment and were seeded on the cut slopes by hands in April, May, June, September and October. In order to identify the best seeding time, germination percentage, ground cover rate and plant height were investigated. There was a difference in germination percentage and ground cover rate depending on the seeding time. The results are summerized as follows 1. Characteristics of germination : Seeding was best carried out in spring(May, June) or autumn(September). In spring, Lespedeza cyrtobotrya shows quick germination and rapid growing which can be compared with herbaceous plants using in the hydroseeding. As for Pinus thunbergii, there was little difference in germinatin according to different seeding timing. But Evodia daniellii, Parthenocis년 tricuspidata and Alnus hirsuta seem to need seed treatments to improve the seed germination. 2. Ground cover rate : The most rapid growing plant is Lespedeza cyrtobotrya and the next is Amorpha fruticosa. The other plants show extreamly low ground cover rate, so they seem to be surpressed by herbaceous plants which will be mixed for erosion control. 3. Plant height : On 8 weeks later after seeding, the Lespedeza cyrtobotrya which was seeded in June recorded 17.1cm plant height. It will be enouch height to compete with herbaceous plants. As the Parthenocissus tricuspjdata seeded in May shows 27cm plant length, it can be used more frequently on seeding works if the seed germination were improved. In sum, seeding is best carried out in May. When deciding seeding rate for the purpose of hydroseeding, it will be necessary to adjust the woody plants germination percentage according to seeding timing.