Adequate regrowth control of weeds and shrubs has been one of the important problem for pasture establishment by overseeding on reclaimed forest hilly land. This experiment was carried out on sloping shrub land near Anseong, Gyeonggido to evaluate the effects of herbicide application on growth control of native weeds, shrubs and trees. We evaluated 63 different weeds and wood species in the trials, which are grown common in korean forest. Buthidazol and 4 other herbicides (sodium chlorate, glyphosate, U-46 and gramoxone) were sprayed each at two application rates during the period of the most intensive growth, on 20 July 45 days before overseeding of pasture species. Glyphosate and sodium chlorate gave excellant control of growth of all species. However. Uncus effusus, Carex heterostachya, Polygonatum humile, Rubus corchorifolius, Lonicera coeralea and Rhododendron mucronulatum were classified as a tolerant weed and wood species to herbicides. Herbicide buthidazol showed also successive control of regrowth of weeds and wood species. But buthidazol was evaluated as a none available herbicide for use in pasture establishment. because o! their long persist of toxic herbicide residue in soils after treatments. Herbicide U-46 and gramoxone had almost no effect on regrowth of shrubs and tree species

A series of tests was carried out to determine the purity and germination of pasture plant and forage crop seeds imported in 1986 and 1987 at the grassland and forage laboratory, College of Agriculture, Seoul National University, Suweon. At the same time, the results obtained were compared with the National Livestook Cooperatives Federation(NLCF1's seed standards as a guide for determining seed quality. 1. The germination percentages of Potomac orchardgrass, Fawn tall fescue, Aquila Ky bluegrass and California ladino clover among grasses and legumes tested were lower than those of the N1,CF's standards, but the germination percentages of forage crops were higher than those of the NLCF's standards. 2. The purity of Potomac orchardgrass and Aquila Ky bluegrass were relatively lower than those of the NLCF's standards. 3. The percentages of other crop seeds in Potomac orchardgrass, Fawn tall fescue, Aquila Ky bluegrass and Cayuse oats were lower than those of the NLCF's standards. 4. Percentage of inert matter in the seeds was lower compared with the NLCF's standards except Akela ' forage rape. 5. The seeds of Potomac orchardgrass, NK 367 sorghum hybrid and sorghum x sudangrass hybrids such as NC+855, G83F and TE Haygrazer were contaminated with one or more weed seeds. Rumex spp. was by far the most common weed in the seeds imported. The other weeds occurred at a low level were Rumex acestosella, Senecio jacobaea, Cirsium arvense and Cuscicta spp. 6. There were many variations in 1,000 seed weight among different species. A thousand seed weight of Aquila Ky bluegrass was 0.263g, but that of Tetrone Italian ryegrass, Akela forage rape and Pioneer 3160 sorghum x sudangrass hybrid was 3.875, 3.476 and 242.4578, respectively. 7. According to the fluorescence test of ryegrass seed, Tetrone Italian ryegrass was known as a true annual type, but an unknown cultivar produced in Cheju was contaminated with 6% of perennial ryegrass seed.

Adequate regrowth control of weeds and shrubs has been one of the important problem for pasture establishment by overseeding on reclaimed forest hilly land. This experiment was carried out on sloping shrub land near Anseong, Gyeonggido to evaluate the effects of herbicide application on growth control of native weeds, shrubs and trees. We evaluated 63 different weeds and wood species in the trials, which are grown common in korean forest. Buthidazol and 4 other herbicides (sodium chlorate, glyphosate, U-46 and gramoxone) were sprayed each at two application rates during the period of the most intensive growth, on 20 July 45 days before overseeding of pasture species. Glyphosate and sodium chlorate gave excellant control of growth of all species. However. Juncus effusus, Carex heterostachya, Polygonatum humile, Rubus corchorifolius, Lonicera coeralea and Rhododendron mucronulatum were classified as a tolerant weed and wood species to herbicides. Herbicide buthidazol showed also successive control of regrowth of weeds and wood species. But buthidazol was evaluated as a none available herbicide for use in pasture establishment. because o! their long persist of toxic herbicide residue in soils after treatments. Herbicide 1:-46 and gramoxone had almost no effect on regrowth of shrubs and tree species.

본 시험은 alfalfa파종시 겉뿌림 및 다른 파종방법들이 alfalfa의 생육. 건물수량.조단백질 생산량 및 잡초발생에 미치는 영향을 구명하고자 겉뿌림, 겉뿌림+갈퀴질, 겉뿌림+갈퀴질+쇄압, 경운+산파+쇄압 및 경운+조파+쇄 등 5개 처매구를 두고, 1988년 9월부터 1989년 10월까지 축산시험장 초지시험포에서 수행되였으며, 결과를 요약하면 다음과 같다. 1.경운방법으로 6개월후에 토양산도와 토양의 매화학적 특성은 개선되었다. 2 알팔파의 정착개체수는 갈퀴질이나 쇄압으로 증가하였으며, 겉뿌림보다 경운시 크게 증가 하였다 (P<0.05). 3. 1차 이용시 잡초솔은 갈퀴질이나 쇄압으로 감소하였으며, 겉뿌림보다 경운시 크게 감소하였다. 2차 이용시 잡초솔은 전 시험구에서 현저히 감소하였으나 3차와 4차 이용시 잡초솔은 점차 증가하였다. 4 .알팔파의 건물수량은 갈퀴질이나 쇄압으로 현저히 증가하였으며 겉뿌림보다 경운시 유의적인 증가를 보였고(P<0.05), 경운 산파시 가장 높은 수량을 나타냈다. 5. 2차 이용시 조단백질 생산량은 쇄압으로 증가 하였고, 겉뿌림보다 경운시 크게 증가하였다(p

This experiment was carried out in order to estimate the recovery days of root and stubble to the days after cutting, and contribution of specific stubble weight on the regrowth was examined using the relationships between the dry weight of shoot and yield components, and regrowth parameters by the days after cutting. The varieties examined were Maprima, Manhattan, Tove, Peramo, Caliente, Tempo and P-2 grown under individual plant basis. The results are may be summarized as follows: 1. Dry weight of root and stubble were recovered up to 13.5 and 11 days after cutting, respectively. 2. Dry weight of shoot(regrowth parts+stubble) was affected significantly by the varieties, stages of regrowth and variety x stage of regrowth. 3. The variety with tiller weight type showed higher average productivity of shoot than those of the variety with tiller number type. 4. Absolute growth rate(AGR) of shoot was correlated significantly with regrowth parts, stubble, root and weight of a tiller at the early stage of regrowth(up to 12 days after cutting), and correlated with regrowth parts, stubble, weight of tiller and stubble area at the late stage of regrowth(up to 20 days after cutting). 5. Contribution of specific stubble weight to absolute growth rate of shoot was different between the stages of regrowth. Thus, regrowth parts per specific stubble weight(RP1SSbW) and weight of tiller per specific stubble weight(WT1SSbW) contributed to absolute growth rate of shoot at the early stage of regrowth, and efficiency of specific stubble weight(ESSbW), regrowth parts per specific stubble weight (RPISSbW) and weight of a tiller per specific stubble weight(WT1SSbW) contributed to absolute growth rate of shoot at the late stage of regrowth. 6. Regrowth utilization rate(RUR) was one of the useful regrowth parameter to indicate the regrowth potential of grasses.

This experiment was carried out to determine the effect of pure mineral nitrogen fertilization on dry matter yield and the amounts of advisable mineral nitrogen on grassland according to its age at the "Federal Institue for Agriculture in the Alps" in Austria. The results obtained were as follows: 1. With only PK-fertilizing average dry matter yields per year were progressively declined during the period of the studies. Compared with the relatively younger grassland(1st-5th year) the DM-yields were decreased by 35% in older grassland (11th-final year). 2. Due to the less reduction of DM-yields by mineral nitrogen application according to the age of grassland. With N-fertilizing the reduction of DM-yields in relatively older grassland was less than that of younger grassland by 11-21%. 3. At 4-and 5-cut systems the nitrogen amounts for the highest marginal yield(the "most efficient" Ndressing rate) per ha and year were distinctly declined in the relatively older grassland. 4. Required efficiencies of mineral nitrogen were not influenced by the age of grassland.he age of grassland.

This trial was carried out to investigate the effect of oversowing on the fodder value and the life form of standing crop in the low productive grassland with a western exposure at the Korean Native Cattle Improvement Center in Seosan. Chungnam Province. The results obtained are summarized as follows: 1. The inferior plant community of low productive grassland was improved to the most desirable pasture association by oversowing after herbicide application. At the experimental area most of the native grasses were not suitable for the pasture plant due to less fodder value(0-2). 2. The fodder value of standing crop in the improved grassland with 6.04(grasses: 4.72, legumes: 1.07 and herbs: 0.25) was much more increased by 108% than that of low productive grassland. 3. The life forms of plant community in the low productive grassland were composed of Hemicryptophytes of 36.29'0, Therophytes of 30.47~, Chamaephytes of 17.0% and Geophytes of 16.4%). But by oversowing after herbicide application their life forms of Hemicryptophytes increased greatly by 51.4%, on the other hand Therophytes, Chamaephytes and Geophytes were much more decreased by 25.4, 15.6 and 10.470, respectively.

A field experiment was conducted to evaluate the effects of cattle compost application on the change of soil physical properties and their relationship to yield performance of selected main forage crops. Maize(CV. Suweon 19) and sorghum hybrids(CV. Pioneer 9'31) as a summer crops and winter rye were grown on newly reclaimed red yellow soils(Fine loamy, Typic Hapludults) under different application rate of cattle compost associated with chemical NPK fertilization, from Oct. 1986 to Sept. 1989. Experimental field was laid down as a split plots design with four replications. The results obtained are summarized as follows: 1. Cattle compost application reclaimed soil physical propeties, such as formation of granular structure and water holding capacity, and it result in a great increase of plant growth and the rate of dry matter accumulation. 2. While cattle compost treatment reduced the portion of soild phase of the three phase constituents of soils, it increased the portion of air phase and liquid phase comparatively. 3. Organic matter, N, P, K, and mineral content in soil were markedly increased in the plot treated with compost. 4. Cattle compost application increased fodder production both in maize-rye and sorghum hybrids-rye cultivation. Annual dry matter yield of maize-rye cropping was 2183(NI'K only), 2425(NPK+compvst 3000 kg) and 2800kg/lOa(NPK + compost 6000kg/10a).

남부지방에서 유숙기에 수확한 수수의 사일리지 생산과 지엽출현기에 수확한 수수-수단그라스 교잡 종의 청예사료 생산에 알맞는 파종량을 알기 위하여 수수 2품종(P 931, P 956)과 수수-수단그라스 교잡 종 1품종을 4수준의 파종량(1. 2, 3, 4 kg/lOa)에서 재배하였다. 수수 P 931은 7월 22일, P 956은 7월 31 일에 1차 수확하였고, 수수-수단그라스 교잡종은 7 월 26일,8월 16일에 수확하였으며, 수수의 2차 및 수수-수단그라스의 3차 수확은 수확적기에 도달하지 않았으나 모두 10월 13일에 수확하여 그들의 사료가치와 생산성을 비교한 결과는 다음과 같다. 1. 수수와 수수-수단그라스 모두 파종량간에 수 확기, 간장, 초장, 건물비율은 차이가 없었다. 수수의 건물비율은 26.9~31. 2%로서 품종과 수확차수간에 차이가 없었으나 수수-수만그라스의 1자 수확은 10.0-10.7%, 2차 수확은 18.2~19.9%, 3차 수확은 24.6~27.8%로서 수확차수가 높을수록 건물비율이 높았다. 2. 수수 P 931이 P 956에 비하여 조섬유 함량은 높고, 가용성 무질소물은 더 낮았으나 조단백질과 조 지방 함량은 비슷하였다. 수수는 수수-수단그라스 보다 조단백질과 조회분의 함량은 낮고, 조섬유와 가용성 무질소물의 함량은 높았으나 조지빙은 비슷하였다. 3 .총 건물수량은 P 931>P 956>P 988의 순으로 높았다. 수수와 수수-수단그라스 교잡종의 1차 수확량은 파종량이 증가할수록 높았으나 2차 수확량은 파종량이 많을수록 감소하여 총 건물수량은 파종량 2-4 kg/lOa 사이에서는 차이가 없었다.

샤일리지용 수수와 청예용 수수-수만그라스 교잡 종의 사료생산에 안맞은 수확기를 안기 위하여 수수 2품종(p 931, P 956)과 수수 수단그라스 교잡종 1 품종(P 988)을 재배하여, 수수는 출수기부터 1주일 간격으로 6회 수확하였고 재생한 것은 10월 13일에 모두 수확하였다 수수-수단그라스는 출수 1주전부 터 1주후까지 6회 수확하였고, 재생한 것은 2차 혹은 3차 수확하여 수화시기가 사료의 생산성과 사료가치에 미치는 영향을 조사한 결과는 다음과 같다 1. 수수의 1차 수확과 수수-수단그라스 1,2차 수확의 건물비율은 수확기가 늦을수록 증가하였으나 수수의 2차 수확은 생육기간이 충분하지 않아 1차 수화가가 빠를수록 건물비율이 높았다. 2. 1자 수확에서 수수는 수확기가 늦을수록 잎몸과 줄기+옆집의 구성비율은 감소하나 이삭비율은 증가 하였고 수수 P 956이 P 931 보다 이삭비율의 증가율은 컸으나 줄기+잎집 비율은 감소하였다 그러나 수수-수단그라스는 수획기가 늦을수록 잎몸비율은 감소하고 줄기+잎집 비율은 증가하였다 3 .수수의 l차 수확에서는 수확기가 늦을수록 조단백질, 조섬유 함량은 감소하였고, 가용성 무질소물 은 증가하였으며, 조지방과 조회분은 비슷하였다. 그러나 2차 수확은 1차 수확기가 빠를수록 조단백질과 조회분 함량은 다소 감소하였고, 가용성 무질소물은 증가하였으며, 조지방, 조섬유 함량은 비슷하였다. 수수-수단그라스는 수확기가 늦을수록 1차 수확의 조단백질은 감소하였고, 1차 수확의 조섬유와 1,2차 수확의 가용성 무질소물은 증가하였으며, 나머지는 수확기간에 차이가 없었다. 4 수수의 1차 수확에서는 출수기에서 출수 3주 후까지 건물수량이 증가하였으나 재생수량을 합한 총 건물수량은 수확기간에 차이가 없었다 수수-수단그라스는 수확가가 늦을수록 1차 수확과 1, 2, 3차 수확을 합한 총 건물수량이 증가하였다.

옥수수의 흑조위축병 발생이 심한 경화 경산에서, 흑조위축병 내병성이 다른 사일리지용 옥수수 2품종과 생육기간이 다른 사일리지용 수수 2품종을 6개 파종기(4월 l일, 4월 15일, 4월 29일, 5월 13일, 5월 27일,6월 10일)에 재배하여 옥수수는 황숙기에 1회, 수수는 유숙기에 1차 수확하고, 재생한 것은 10월 1일에 2차 수확하여 건물생산성 비교한 결과는 다음과 같다 1.입묘솔은 옥수수가 수수보다 높았다 옥수수는 품종간 및 파종기간에 입묘솔의 차이없이 91% 이상이었으나 수수는 37. 2~80.3%로서 퍼종기간에 차이가 컸다.2 파종에서 출아까지 소요일수는 작물간, 품종간에 차이가 없었으나 파종이 지연될수록 감소하였다. 출아에서 출사기(옥수수) 혹은 출수기(수수)까지 소요일수는 옥수수 두 품과 수수 P 956은 파종이 지연될수록 감소하였으나 수수P 931은 5웰 13일 이전 파종에서는 비슷하였고, 그 이후에는 파종이 늦을수록 소요일수가 현저히 증가하였다. 3 . 옥수수의 흑조위축병 이병솔은 4월 1일 파종에서 가장 높았고(광안옥 24. 8%,진내옥 63.0%), 4윌 2 29일까지는 파종이 지연될수록 감소하였다가 다시 증가하였으며, 수수는 이병되지 않았다 4 . 전식물체 중 이삭비율은 옥수수(30.6~47.9%) 가 수수(3.1~30.7%) 보다 높았고, 품종간.파종기간 차이는 옥수수에서 보다 수수에서 더 컸다. 옥수수와 수수 P 956은 수정에 지장이 없었으나 수수 P 9 931은 5월 13일 이후의 파종에서는 수정불량으로 이삭이 잘 발달하지 못하였다 5 . 조단백질과 조회분은 작물간, 품질간, 파종기간에 큰 차이가 없었다 이삭발육이 나빴던 수수 P 931은 옥수수와 P 956 보다 조섬유는 높고, 가용성 무질소물은 낮았다. 옥수수와 1차수확한 수수는 파종기간에 조섬유, 가용성 무질소물에 큰 차이가 없었으나 재생한 수수는 파종이 늦을수록 조섬유와 가용성 무질소물은 감소하고 단백질 함량은 증가하였다 6 . 옥수수와 수수 모두 파종이 지연될수록 건물수량이 감소하였으나 진내옥은 4월 29일 파종에서 보다 그 이전의 파종에 서 수량이 더 낮았다. 옥수수의 건물수량은 수수의 1차수량과 비슷하였지만 재생한 2차수확을 합하면 재생량이 많은 4월 파종에서는 수수가 옥수수보다 건물수량이 현저히 많았다.

For the constitution of forage cropping system including the double-cropping of corn, attention has been directed towards the early and short maturing varieties of corn such as Comet 80, Comet 85 and Linda as a component forage crop of forage cropping system. Four corn varieties, Comet 80, Comet 85, Linda and Suwon 19 were planted delayedly by each of 45, 55 and 65 days from the recommended sowing date of suwon 19. Under these condition, growth characteristics and late-sowing adaptability of 4 corn varieties were investigated, and the results are summarized as follows; 1. The variety of suwon 19 did not reach the stage of silking in the occasion of late sowing by 50 days from the optimum sowing time for mono cropping of suwon 19. However early varieties such as Comet 80, Comet 85 and Linda silked under the condition of 65 days-delayed sowing from the recommended sowing time of Suwon 19 for mono-cropping. 2. Early varieties of Comet 80, Comet 85 and Linda were so grown by approximately 92% in plant height, 66% in ear height, 88% in stem diameter and 81% in leaf number respectively compared to Suwon 19 at each of three delayed sowing time that exhibited the dwarfish appearance of canopy. 3. Days from sowing to silking decreased as the sowing time was delayed and the average days from sowing to silking in the sowing treatments of 55 days-delayed of Suwon 19, Comet 80, Comet 85 and Linda were 61, 46, 47 and 51 days, respectively. 4. The size of variations of plant height and ear height influenced by delayed-sowing time was comparatively larger in the varieties of Suwon 19 and Linda than in those of Comet 80 and Comet 85. 5. As sowing time was delayed from the optimum sowing time of Suwon 19 for mono-cropping, ear content decreased from 0% of Suwon 19 at 55 day-delayed sowing treatment to 3540% of Comet 80 and Comet 85 at 65 days-delayed sowing treatment.