• Journal of The Korean Society of Grassland and Forage Science
• /
• v.19 no.4
• /
• pp.355-362
• /
• 1999

This experiment was conducted to evaluated the effect of maturity at harvest and wrap colors on the quality of round baled rye(Secal cereale L.) silage at the forage experimental field, Grassland and Forage Crops Division, National Livestock Research Institute, Suwon in 1998. The experiment was consist of split-plot design with three repications. The main plots were three different harvesting stages : boot, heading, and flowering stages, the subplots were wrap colors : white, black, and light green color. Acid detergent fiber(ADF) and neutral detergent fiber(NDF) of rye silage were increased with delayed harvesting date, but there were no significant differdence among wrap colors. However, average in vitro dry matter digestibility (IVDMD) of rye silage with white color wrap tended to have higher than those of other colors. The silage pH of heading stage was highest (5.12), and that of flowering stage was lowest (4.57) in different harvest stages. Among tested wrap colors, white color wrap resulted on lowest pH than others (p<0.05), but there were no significant difference between black and light green color. Dry matter (DM) content of rye silage were increased as harvest stage progressed (p<0.05). However, DM content of white color was highest among warp colors, but there was signifiant difference (p<0.05). Ammonia-N content of silage harvested at boot stage was the highest in harvest stage, but there was no difference between heading and flowering stages. Among wrap colors tested, ammonia-N content of black color was highest, but there was no significant difference. The number of lactic acid bacteria of white colors was highest in different colors, and that of flowering stage was highest among harvest stage. Acetic and butyric acid contents were decreased as harvest stage progressed, and lactic acid was increased from 6.33 to 7.98%. However, wrap colors did not influence lactic acid concentration. Among different wrap colors, outside temperature of rye silage was affected by air temperature, but effect of inside temperature was minimal. Black color wrap increased inside temperature by $3{\sim}5^{\circ}C$. The results of this study indicate that rye should be harvested for round bale silage after heading stage. The quality of rye silage wrapped white and light green color will increase slightly.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.19 no.4
• /
• pp.347-354
• /
• 1999

This experiment was carried out to determine the effect of maturity at harvest and inoculants on the quality of round baled rye(Secale cereale L.) silage at the experimental field of Grassland and Forage Crops Division, National Livestock Research Institute, RDA, Suwon in 1998. The experiment was consist of split-plot design with 3 replications. The main plots were 3 harvesting stages such as boot(20 April), heading(29 April), and flowering stages(14 May). The subplots wered inoculant treatments : control (untreated), inoculant A, and inoculant B. Acid detergent fiber(ADF), neutral detergent fiber(NDF), and in vitro dry matter digestibility (IVDMD) of rye silage were significantly increased with delayed harvesting date, but there was not significant difference between inoculants. Mean silage pH at flowering stage was the lowest(4.35), but the highest at early harvest(4.91). Inoculants significantly reduced acidity of silage compared with control. Dry matter(DM) content of the control was higher than that of inoculants. Ammonia-N as proportion of total N was below 10% which was maximum level of high quality silage. The addition of inoculants reduced ammonia-N. There were significant difference in organic acid contents between harvesting stages and inoculants. Lactic acid was increased with inoculants, but acetic and butyric acids were decreased. Various treatments increased colony forming unit(CFU) of lactic acid bacteria by 2 or 3 times compared with the control and the highest at flowering stage with inoculant B treatment. Results of this study indicate that use of microbial inoculant and harvesting after heading stage will improve the silage fermentation and quality of round baled rye silage.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.19 no.4
• /
• pp.339-346
• /
• 1999

This experiment was carried out to determine harvest date and cultivar effects on the agronomic characteristics, forage yield, and quality of fall sown oat (Avena sativa L.) at the forage experimental field, College of Agriculture and Life Sciences, Seoul National University, Suweon from August to November 1993. The experiment was arranged in a split plot design with three replications. The main plots were consisted of the harvesting dates, suchas early (11 October), mid(21 October), and late(1 November), the subplots were consisted of different maturities of oat cultivars, such as 'West', 'Cayuse' and 'Magnum'. The first heading date of an early maturing culivar, West, was observed on 10 October, and the heading increased up to 30% at the late harvesting date. The average dry matter (DM) content of oat cultivars increased significantly from 12.8 to 15.9% as the growing stage progressed(p<0.01). The average dry matter percentage of West, Cayuse, and Magnum was 15.4, 13.4, and 13.5%, respectively. The crude protein (CP) content of oat cultivars decreased significantly from 20.1 to 13.3% as the harvesting date was delayed(p<0.01), and the CP contents of midseason and late maturing cultivars, Cayuse and Magnum, respectively, were significantly higher than that of an early maturing cultivar West (p<0.01). The mid harvesting date showed the highest acid detergent fiber(ADF) and neutral detergent fiber (NDF) contents than the other harvesting dates, and an early maturing cultivar West had higher ADF and NDF contents than the midseason and late maturing cultivars, Cayuse and Magnum, respectively. The in vitro dry matter digestibility(IVDMD) of oat cultivar West decreased as the harvesting date was delayed, but that of Cayuse and Magnum decreased only by the mid harvesting date. Cayuse and Magnum showed 3~4% higher digestibility than West. The correlation coefficient between IVDMD and ADF content was -0.86. The average dry matter yield of oat cultivars increased from 2,901 to 5,901kg/ha as the harvesting date was delayed(p<0.01), but no significant difference was found among oat cultivars. The corrdelation coefficient between DM yield and gorwing degree days(GDD) was +0.86. The results of this study indicate that a delay in harvesting date would be recommendable for the increase of dry matter yield when fall-sown oat is grown. Especially, the DM yield of the midseason and late maturing cultivars, Cayuse and Magnum, respectively, can be increased without much change of forage quality although the harvesting date are delayed.

• Korean Journal of Plant Resources
• /
• v.26 no.1
• /
• pp.26-35
• /
• 2013

This study was conducted to select superior provenances of Scots pine (Pinus sylvestris L.) well adapted to Korean environment for timber production. In 1976, twenty-two provenances of Scots pine were introduced from Sweden and the seeds were sown in seed beds in March. After one year, the seedlings were transplanted to nursery beds. The resulting 1-1 seedlings of 22 provenances were planted at Whaseong in 1978. Randomized complete block design with 3 replications were used for test plantation. Each provenance was planted with 20-tree row plot in each block and at a spacing of $1.8{\times}1.8m$. The growth performance of each provenance was monitored up to 33-years after planting. There were significant differences among provenances in volume growth. F3001 provenance showed the best volume growth of 33-years after planting ($0.160m^3$), which was 2.2 times greater than that of the lowest provenance W2027 ($0.072m^3$). The ranking of provenances was stabilized after 14 years. Comparing to reference tree species, Japanese red pine (Pinus densiflora), all Scots pine provenances showed poor growth performance. In other words, volume growth of Japanese red pine at age 28 and 33 were 2.1 and 3.3 times greater than that of Scots pine, respectively. Moreover, survival rate of Scots pine was lower than that of Japanese red pine. Based on these results, it was suggested that Scots pine was not suitable to Korean environments. The cause of maladaptation of Scots pine and the implications of introduction breeding were discussed.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.6 no.1
• /
• pp.1-11
• /
• 1986

Welded connectors of the cover plates, the transverse stiffeners of the plate girders, and the gusset plates of the plates girders or box girders, were selected as studying objects. A simplified method of drawing the S-N curves in these welded joints by a computer program without the direct fatigue tests was established. The plots on the S-N curve using the values from the practical fatigue tests were compared with the results from the method of the computer programming. The results of these studies are as follows. It appeared that the fatigue life by calculation method was a little less than the practical fatigue life from the actual tests. The latter values included both life $N_c$ of occurrence of initial crack $a_i$ and the life $N_p$ of propagation of critical crack. On the other hand, the former values included only the life $N_p$. Therefore, these results should be considered as justifiable ones. Since the difference between the two results was not significant, the results by calculation method should be in the conservation side when the safety of the structures was considered. Consequently, the results by calculation method should be applicable to the fracture fatigue design of structure. For reference, the same fatigue tests were performed with the specimens of 3 pieces in each case made of the low-strength steel, SS 41. The results went unexpected showing that the fatigue strength was lower in the case of low-strength steel. That is, in the case of the cover plate, the fatigue strength became slowly higher than the case of high-strength steel, SWS 50. That was observed when the maximum testing stress was higher than $14kg/mm^2$. In addition, in the case of the transverse stiffener, the fatique strength became rapidly higher than the case of SWS 50. That was observed when the maximum testing stress was lower than $31kg/mm^2$. It was thought that more such fatigue tests should be performed for more reliable results.

• Asian Journal of Turfgrass Science
• /
• v.18 no.3
• /
• pp.129-139
• /
• 2004

This study conducted to find out the best way to prolong green period of Zoysiagrass and Cool-season grass from 1999 to 2001 in Korea. Treatments were control, vinyl, black shade net, green shade net, black shade net+vinyl, green shade net+vinyl, vinyl+black shade net, and vinyl+green shade net for Zoysiagrass. For cool-season grass, treatments were control, non-punched vinyl and punched vinyl. Data on temperature, light intensity, humidity, leaf color and chlorophyll were collected. Plot size was 2 by 2 and the experiment was conducted using completely randomized design with three replication. Zoysiagrass Green period of Zoysiagrass depended on temperature and light intensity than humidity. Effective method of prolongation of green period in Zoysiagrass was to covered it with vinyl during early October to early November, and then using vinyl+black shade net from end of November. Cool-season grass Effective method of prolongation of green period in Cool-season grass was by covering it with vinyl during mid-November to mid-December, and then using vinyl+black shade net from end of December.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.32 no.2
• /
• pp.117-124
• /
• 2012

This study was conducted to estimate Hanwoo carrying capacity when whole crop barley or rye as winter forage crops was grown on different applying sources (chemical fertilizer, cattle or organic fertilizer) and mixed sowing combination with hairy vetch or forage pea during the period of 2008~2010. The experimental plots within whole crop barley or rye were consisted of 7 treatments, which were non-fertilizer, chemical fertilizer (P+K), chemical fertilizer (N+P+K), organic fertilizer, cattle slurry, cattle slurry with hairy vetch, and cattle slurry with forage pea. Each plot was triplicates and experimental treatments were allocated in the randomized complete block design. For whole crop barley, annual mean dry matter (DM) and total digestible nutrients (TDN) yields were the highest in N+P+K plots, but there were no significant differences among organic fertilizer, cattle slurry and mixed sowing with legumes. The TDN and RFV were the highest in mixed sowing plots of forage pea plus cattle slurry application. As 450 kg Hanwoo heifers were fed diets included 70% whole crop barley, organic fertilizer, cattle slurry application and mixed sowing with legumes plots is capable of raising average 2.5 to 2.9 heads/ha a year. For whole crop rye, annual DM, crude protein, and TDN yields of application groups and mixed sowing treatment with legumes showed 6.69~7.13, 0.46~0.51 and 3.95~4.18 ton/ha, respectively. In case of 450 kg Hanwoo heifers fed diets included 70% forage rye, it is estimated that cattle slurry application (mixed sowing with legumes) plots can rear average 3.1~3.3 heads/ha a year. It can be concluded that, on the basis of DM yield, not only mixed sowing with legumes by applying cattle slurry rather than single sowing of whole crop barley or whole crop rye enhanced production yield and feed values, but also it could be a substitute for imported grains as dietary protein sources in the case of feeding Hanwoo.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.14 no.3
• /
• pp.238-246
• /
• 1994

This experiment was carried out to determine the effects of seeding date and fall harvest method on the growth characteristics, forage yield and quality of winter rye(Seca1e cereale L.) at the forage experimental field, College of Agriculture and Life Sciences, SNU, Suweon from 5 September 1992 to 21 May 1993. The experiment was arranged in a split plot design with three replications. Main plots consisted of three harvests, no defoliation, cutting and grazing. Sub-plots consisted of seeding dates, early(5 September), mid(25 September) and late(l0 October). The results obtained are summari7d as follows; I . A 3-day difference in the first heading of rye was observed between no defoliation and fall grazing, while there was a 6day difference between early and late seeding dates. Therefore, the effect of seeding dates on the fist heading date of rye was larger than that of fall harvest methods. 2. CP content of rye with fall grazing was slightly higher averaged 16.5% compared with both fall cutting and no defoliated 1ye(15.6%). Mean CP content of rye at the early, mid and late seeding dates was 14.2, 14.5 and 19.1 %, respectively. 3. ADF content of rye was slightly higher with both fall cutting(29.99) and no defoliation(29.5%) than that of fall grazing(28.0%). ADF content of rye at the early, mid and late seeding dates was 30.7, 29.1 and 27.7%, respectively. Effect of fall harvest methods and seeding dates on NDF content of rye were similar to the observations made on ADF. 4. RFV and IVDMD of rye were lower with both no defoliation and fall cutting than fall grazing. but those of rye slightly increased with seeding dates progressed. 5. Dry matter yield of rye was the highest of 6,779 kg/ha with fall cutting, while the lowest yield of 6,240 kg/ha was obtained from no defoliation But no significant difference was found among the harvest methods. Dry matter yield of rye was significantly declined with later seedings. It is concluded that the highest forage yield of rye be possible from two harvest systems of fall and spring with earlier seeding rather than from one harvest system of spring.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.24 no.4
• /
• pp.317-323
• /
• 2004

This study was carried out to determine the effect of seed method and seeding rate on the desirable agronomic characteristics and yield of forage barley(Hordeum vuigare) at paddy field, National Livestock Research Institute, RDA, Suwon from October 2001 to May 2003. The experiment was arranged in a spilt plot design with three replications. Main plots consisted of tow seed method; Broadcasting and drilling, Sub-plots consisted of seeding rates; 130. 160, 190 and 220 kg/ha. The results obtained were summarized as fellows ; The resistance of cold, disease and lodging of barley for the seeding method and seed rate were not different. And dry matter percentage of barley for a seeding method of 130 kg/ha at the broadcasting was the lowest of $32.0\%$, and that for the drilling at 130 kg/ha was $32.7\%(P<0.05). Fresh yield of barley for a seeding method of drilling at 130 kg/ha was the highest of 32,073 kg/ha, and that for a seeding method of broadcasting at 130 kg/ha was the lowest of 20,944 kg/ha(P<0.05). Dry matter yield of barley for a seeding method of drilling at 160 and 130 kg/ha were the highest 9,170 and 9,138 kg/ha, and that fur a seeding method of broadcasting at 130 kg/ha was the lowest of 5,710 kg/ha(P<0.05). Based on the results of this experiment, it appears that the seeding method and rate of barley could be enhanced by drilling from 130 to 160 kg/ha, and broadcasting from 190 to 220 kg/ha. respectively.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.25 no.4
• /
• pp.239-244
• /
• 2005

This study was conducted to investigate the effect of the planting densities and nitrogen levels on the growth characteristics, dry matter yield and nutritive value of corn for silage in alpine area(altitude 800m a.s.1.) of National Livestock Research Institute from 2001 to 2002. The experiment was arranged in a split plot design with three replications. Main plots consisted of three planting densities, low(67,000 plants/ha), medium(89,000 plants/ha) and high(95,000 plants/ha). Sub plots consisted of three nitrogen levels, 150 kg/ha, 200 kg/ha, and 250 kg/ha. Tassel height of corn was increased with decreasing planting density, and nitrogen level of 200 kg/ha in all main plots. Ear height of corn was decreased with increasing planting density, and 150 kg/ha of three nitrogen levels. But there were no significant differences among treatment in tassel and ear height. Although dry matter ear ratio of whole com was increased with decreasing planting density, there were no significant differences among treatments. But there were significant differences among nitrogen levels(P<0.05). Dry matter yield of com was high with increasing planting density, but there were no significant differences among treatments. And DM yield of corn was significant difference among nitrogen levels(P<0.05). Crude protein content of corn was the highest with high planting density and low nitrogen level. NDF and ADF content of com was the highest with low planting density and nitrogen levels of 200 kg/ha in all main treatments. These results indicate that low planting density(67.000 plants/ha) and nitrogen of 150-200 kg/ha would be the optimum level fur dry matter yield and nutritive value of silage com in alpine area.