• Journal of The Korean Society of Grassland and Forage Science
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• v.15 no.2
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• pp.93-100
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• 1995

This experiment was carried out to investigate how to effect the application of nitrogen, phosphate and potassium on the vegetation and dry matter yield in the mixed sward of orchardgrass and crabgrass (Digitaria sanguinalis [L.] Scop.). The experimental sward wa5 consisted of eight plots of non-application, P, K, PK, N. NK, NP and NPK. These plots were sown with seeds mixture of orchardgrass 17.5 kglha and crabgrass 17.5 kg/ ha on 22 April 1975 in the forage experimental field of Kangwon National University, Chunchon, Korea, and were cut four times from 6 July to 18 November 1975. The results obtained were summarized as follows: 1. In orchardgrass density measured after summering, the plot of nitrogen applied without phosphate marked only 3 1.0% of the plot of nitrogen applied with phosphate while in crabgrass density measured at that time the plot of nitrogen applied without phosphate marked as high as 112.5% of the plot of nitrogen applied with phosphate. 2. Application of phosphate and potassium improved wintering record of orchardgrass. In orchardgrass density measured after wintering, the plot of nitrogen applied without phosphate marked only 9.7% of the plot of nitrogen applied with phosphate, and the plot of NP applied without K marked 63.6% of the plot of NP applied with K. 3. In surface coverage of orchardgrass, in midsummer any plot applied with nitrogen regardless of accompanying with or not with phosphate wa5 0%, but in autumn the plot of nitrogen applied with phosphate was 56-58% and the plot of nitrogen applied without phosphate was 5%. While after wintering the plot of nitrogen applied with phosphate was 28-37% though the plot of nitrogen applied without phosphate was only 0.3-0.6%; the application of phosphate improved summering and wintering record of orchardgrass. 4. Application of phosphate demonstrated remarkable effect on increasing dry matter yield in orchardgrass. In year total yield of orchardgrass, the plot of nitrogen applied without phosphate marked as low as 11.3% of the plot of nitrogen applied with phosphate, but in crabgrass the plot of nitrogen applied without phosphate was almost equal to the plot of nitrogen applied with phosphate showing 97.5% of this plot. 5. Application of potassium was not effective on increasing dry matter yield of orchardgrass but its application was effective on increasing dry matter yield of crabgrass. In dry matter yield of orchardgrass significant difference was not found between NP plot and NPK plot, but in dry matter yield of crabgrass NPK plot recorded significantly higher yield compared with NP plot (p<0.05). 6. In botanical composition of the plot of nitrogen applied with phosphate, crabgrass recorded 46.5-50.5% in early summer (July) but in midsummer (August) it dominated the plot recording 85.6-91.2%. 7. In botanical composition based on the year total yield, in the plot of nitrogen applied with phosphate orchardgrass marked 21.7-26.2% and crabgrass recorded 73.8-78.370, but in the plot of nitrogen applied without phosphate orchardgrass marked only 3.5% being overwhelmingly dominated by crabgrass which recorded 96.5%. 8. Application of nitrogen not accompanied with phosphate strengthened competitive power of the crabgrass unilaterally, making orchardgrass be oppressed fatally by the crabgrass.

• Journal of The Korean Society of Grassland and Forage Science
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• v.19 no.3
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• pp.197-202
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• 1999

This study was conducted to evaluate the dry matter yield, quality and utilization of nutrients of crabgrass (Digitaria sanguinalis L.) dominant swards as a roughage sources. Dry matter yield of stages, chemical composition, DM digestibility was obserbed, and DM intake, digestibility and utilization of nitrogen and energy by Korean native goats was determined. Average DM yield of crabgrass dominant swards was obtained 8,473kg/ha, and average contents of CP, NDF, ADF and lignin was 13.0%, 74.1%, 38.6% and 10.4%, respectively. DM intake by Korean native goats was lower for crabgrass dominant swards than for sown grass swards(P>0.05). Digestibility of DM, celluar constituents, NDF and ADF by Korean native goats was significantly lower for crabgrass dominant swards than for sown grass swards(P<0.05). Utilization of nitrogen and energy by Korean native goats was significantly lower for crabgrass dominant swards than for sown grass sward(P<0.05). Above the results, although crabgrass dominant swards was lower than in DM yield, digestibility, and utilization of N and energy, but the DM yield of crabgrass dominant swards was obtained 8,471kg/ha without fertilizer. Therefore it appears that crabgrass dominant swards have a potential to provide roughage sources.

• Journal of Biosystems Engineering
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• v.24 no.1
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• pp.59-66
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• 1999

Weed identification is important for precision farming. A machine vision system was applied to detect weeds. Shape features were analyzed with the binary images obtained from color images of radish, purslane, goosefoot, and crabgrass. Features studied were aspect, roundness, compactness, elongation, PTB, LTP, LTW, and PTAL of each plant. Discriminant analysis was used to classify plant species. The best shape features that distinguished crabgrass were LTP and LTW which distinguished the crabgrass from the others with 100%. Two dimensional discrimination by using LTP and PTB appeared to be effective for distinguishing radish, purslane, and goosefoot.

• Korean Journal of Environmental Agriculture
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• v.7 no.1
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• pp.52-57
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• 1988

This study was carried out to investigate the specific activity fo peroxidase(POD) in conjunction with the phytotoxic effect of the tolerant soybean(Glycine max Merr.) and the susceptible crabgrass(Digitaria adscendens(L.) Scopol.) to acifluorfen. The POD activity increased during the growth of soybean and crabgrass seedlings. But after the foliar application of acifluorfen, the POD activity in the treated leaves was considerably higher than in controlled leaves, suggesting that soybean had higher tolerance to acifluorfen with growth. All the treated soybeans recovered from herbicidal injury in 14 days after treatment, while all the treated crabgrasses were dead with extreme necrosis and leaf burning. It was measured that the POD activity of crabgrass increased abruptly in 1 to 2 days after treatment and then significantly decreased in 5 days.

• Journal of The Korean Society of Grassland and Forage Science
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• v.16 no.2
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• pp.139-146
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• 1996

An experiment was canied out to investigate how to effect the application of nitrogen, phosphate and potassium on the vegetation and dry matter yield in the mixed sward of Ladino clover and crabgrass(Digitaria sanguinalis [L.] Scop.). The experimental sward was consisted of eight plots of non-application, K, P, PK, N, NK, NP and NPK. These plots were sown with seeds mixture of Ladino clover 5.0kg/ha and crabgrass 17.5kg/ha on 17 April 1976 in the forage experimental field of Kangwon National University, Chunchon, Korea, and were cut three times from 6 July to 4 October 1976.

• Asian Journal of Turfgrass Science
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• v.12 no.2
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• pp.99-106
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• 1998

미국내에서 바랭이의 지역적 분포와 각 재배작물에서 잡초로서의 중요성을 자료화하기 위하여 설문조사를 실시하였다. 총 117개의 배포된 설문지중 72개의 설문지가 회수되어 62%의 응답률을 보였다. 미극내의 농, 원예작물 재배지역에는 5종의 바랭이가 분포하는 것으로 보고되었고, 이들은 large, smooth, southern, india 그리고 blanket crabgrass 등이었다. 이들 중 약 50% 이상의 응답자가 large crabgrass를 가장 문제잡초로 인식하고 있었다. 지역적으로 smoth와 large crabgrass는 모든 위도에서 그 우점도가 인정된 반면, southern crabgrass는 우점도가 남부지역에 제한되는 것으로 보고되었다. 바랭이는 다른 작물의 재배지역보다 잔디밭에서 그 문제가 보다 심각한 것으로 보고되었다. 남부지역의 잔디밭에서는 large, southern 그리고 smooth crabgrass의 순서로, 북부지역에서는 smooth crabgrass가 large crabgrass보다 잡초로서의 문제성이 큰 것으로 보고되었다. 대부분의 응답자들은 종내변이성이 smooth와 large crabgrass에는 존재하지 않는 것으로 응답하였으나, southern crabgrass내에는 존재하는 것으로 보고되었다.

• Asian Journal of Turfgrass Science
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• v.15 no.3
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• pp.127-136
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• 2001

A field trial was initiated to examine the range of inter- and intraspecific variations in morphological and phenological traits with five different accessions of smooth and large crabgrass. In addition, a controlled environment study was conducted to determine the phenotypic plasticity among the accessions of both species in response to 4 daily tempera-ture differentials. In the field experiment, significant inter- and intraspecific variations of smooth and large crabgrass were observed in morphological traits such as leaf length and width. However, most phenological traits were not substantially different between the species and among the accessions of each species. The first seedling emerged at the same time, requiring 9~ 10 days, regardless of the accessions and species. In a controlled environment study, all accessions of each species responded similarly to the 4 temperature differentials in seedling emergence, indicating seedling emergence was not a plastic trait. These results suggest that predicting crabgrass seedling emergence could be independent of geographical regions in the US.

• Journal of Ecology and Environment
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• v.47 no.4
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• pp.250-260
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• 2023

Background: Crabgrass (Digitaria ciliaris, Poaceae) is a globally distributed weed, including in Afro-Eurasia, America, and Australia. As a highly gregarious plant, crabgrass is an important habitat for a diverse array of insects, and a potential habitat for agricultural pests. To compare the insect communities associated with the crabgrass community, insects were sampled using sweep sampling (100 sweeps per sample) at five sites, including Daejeon (Daejeon and Gap rivers), Anseong, Namhae, and Inje, with a focus on the Daejeon River. Results: A total of 5,888 individual insects belonging to eight orders, 42 families, and 115 species were collected from the five sites. Both the number of species and individuals of Hemiptera were the highest at all of the sites. In the present study, 73% of the insect population fed on D. ciliaris as a host plant. The dominant species in the D. ciliaris community was Laodelphax striatellus (Delphacidae), being ubiquitous at all the sites which showed a high abundance of rice pests in the communities and the suitability of D. ciliaris as an alternative host plant for them. The Shannon-Wiener diversity index was highest in Inje on 17 September (2.88), and the Chao1-bc diversity index was highest in the Gap River on 5 September (80). The sampling efficiency of 100 sweep samples (sample coverage) was calculated to be as high as 90%. The results of the samples taken from September to November in the Daejeon River showed that the number of species and individuals decreased gradually over time, and the number of dominant species decreased sharply between September and October. Similarity analysis indicated that sampling dates that were closer together yielded sampled assemblages with higher faunal similarity. In addition, in each sampling, the difference in the minimum temperature during the two-week period prior to sampling and faunal similarities were negatively correlated. Conclusions: This study provides foundational data that could enhance our understanding of insect diversity in D. ciliaris. The data can facilitate ecological conservation and management of Korean grasslands generally, as well as identification of potential pests that may disperse from D. ciliaris communities to nearby farmland.

• Asian Journal of Turfgrass Science
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• v.26 no.1
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• pp.60-66
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• 2012

Crabgrass (Digitaria sanguinalis L.), Dandelion (Taraxacum platycarpum H. DAHLST.), Annual bluegrass (Poa annua L.), Gree kyllinga (Kyllinga brevifolia var.), Red clover (Trifolium pratense L.), Annual lespedeza (Kummerowia striata (Thunb.)Schindl.), Mugwort (Artemisia capillaris Thunb.), Horseweed (Erigeron canadensis L.), Field horsetail (Equisetum arvense L.) are major weeds in turf. In this study, 23 medicinal plant extracts were tested for herbicidal activities against crabgrass and dandelion in the course of major weed in turf. In pot experiment, we implemented pre-emergence application used medicinal plant extracts showed herbicidal activity in petridish experiment. In effect, inhibition rates of germination were 61.0% at Curcuma longa extract and 62.5% at Cnidium officinale extract in crabgrass pot experiment, and 77.8% at Ailanthus altissima extract in dandelion pot experiment.

• Journal of The Korean Society of Grassland and Forage Science
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• v.26 no.2
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• pp.105-112
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• 2006

This experiment was carried out to investigate the distribution, function of dry matter and competition in the grassland composed with mainly perennial ryegrass. Co-functions between grasses and weeds were evaluated by calculating methods; expected yield (P), agressivity, relative yield total (RYT), compensation index (CI) and morphological index (MI). Each values obtained were influenced by seeding method, grassland management and seasonal changes of co-functional index were identical. Expected yields of spring were lower than those of fall and improved by additional seeding to grassland in early spring time. In the relative yield total (RYT), all were under 1.0 which ranged from 0.17 to 0.41. Compensation index (CI) ranged from -0.3 to -0.6 and all values showed 'under compensation(+, --)' This means that the conditions of 'under compensation' could be improved through weed control by management of grassland in perennial ryegrass grassland. The results indicated that productivity of grassland mainly composed with perennial ryegrass is negatively affected by weeds like shepherd's purse, crabgrass and barnyard grass. As major weeds, shepherd's purse in spring, crabgrass in summer and barnyard grass in summer and fall were negatively functioned to productivity in the grassland composed with mainly perennial ryegrass.