• Journal of Forest and Environmental Science
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• v.31 no.2
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• pp.91-108
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• 2015

The study investigates herbage communities along the altitudinal gradient in northwest Himalaya and highlights the effect of trees on its understory floristic diversity and phytosociology. The study was conducted in nine forests at three elevations viz., chir pine (Pinus roxburghii), mixed and khair (Acacia catechu) forests at elevation $E_1$ (850-1150 m), chir pine, mixed and ban oak (Quercus leucotrichophora) forests at elevation $E_2$ (1151-1600 m) and ban oak, mixed and chir pine forests at elevation $E_3$ (>1600 m) in a sub-watershed located in Solan district of Himachal Pradesh, India. These were compared grasslands located adjacent to forests. In all, 20 grass, 3 sedge, 2 forb and 4 legume species were recorded in study sites. Jaccard's coefficient of herbage vegetation was highest between chir pine forests and grasslands, and lowest in khair and ban oak forests. TWINSPAN dendrogram of herbage composition exhibited three subtypes with Apluda mutica, Arundinella nepalensis and Dichanthium annulatum as indicator species. Three groups of plant communities were identified on the basis of their moisture requirement. Peak density and basal area of herbage in forests and grasslands occurred by September. Density and basal area of herbage in grasslands at different elevations ranged from 649.6 to $1347.9tillers/m^2$ and 30.0 to $65.7cm^2/m^2$, respectively, while, in forests it varied from 351.2 to $1005.3tillers/m^2$ and 14.9 to $43.9cm^2/m^2$, respectively. Density and basal area of the herbage in plant communities decreased along the elevation. Under trees in forests the density of herbage decreased up to 77% and basal area up to 62% of their respective values in grasslands.

• Journal of Forest and Environmental Science
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• v.34 no.4
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• pp.338-351
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• 2018

This study was conducted in a long-term experimental forest in the central hardwoods region of southwestern Michigan to retrospectively examine the role of past forest management practices and climate on red oak (Quercus rubra L.) productivity. Initially, in 1971, plots within the experimental forest were treated separately with a clearcut and shelterwood regeneration harvest in an attempt to increase red oak regeneration. From 1987-1989, a new study was initiated within a portion of the clearcut and shelterwood plots to evaluate the effectiveness of additional oak crop tree release using mechanical and chemical applications. Cumulative diameter and mortality rates of 719 red oaks were monitored across the four silvicultural treatments: Clearcut-A (clearcut without additional release treatment), Clearcut-B (clearcut with additional release treatment), Shelterwood-A (shelterwood without additional release), and Shelterwood-B (shelterwood with additional release) plus an untreated control. Increment cores were obtained from red oak trees and neighboring competitor species. Tree-ring analyses (dendrochronology) were applied to examine the effect of these silvicultural treatments and climatic factors (temperature and precipitation) on red oak productivity. The results indicated that crop tree release following a clearcut or shelterwood harvest reduced mortality rates and thus increased survival of red oak. Red oak in control plots or plots only receiving the initial regeneration harvesting treatment and no additional competition release were negatively affected by climatic stress, which included summer moisture stress. In contrast, red oak in plots that received the competition release treatment from shade tolerant tree species not only had higher tree level productivity (i.e., tree basal area) and lower mortality rates, but were also relatively more resilient to climatic stress by showing limited or no associations between climate and growth.

• Korean Journal of Agricultural Science
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• v.10 no.1
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• pp.9-21
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• 1983

The structures of oak stands were studied in relation to their productivity. Three plots classified by the site quality following to altitude, were selected on the oak stand located at Naryongri Eunsanmyun Buyeogun. The site qualities of the stand studied were generally estimated to be moderate in respect to some soil physical and chemical properties. Quercus variabilis was dominant species in the vegetation composition of the stand studied. The crown densities of the stand were varied from 65.4% in plot I to 78.2% in plot III and the parts, occupied with oak trees, ranged from 44.4% in plot I to 65.9% in plot III in the density. In the contrast to crown density, the growing stocks of oak trees ranged from $3.937m^3$ in plot I (73.4% of plot total) to $2.075m^3$ in plot III (84.3% of plot total). The occupied ratios, measured by crown class, exhibited dissimilarity between crown projection area and volume, and also the ratios brought into different patterns by plot. Highly significant correlations were proved between crown projection areas and volumes of individual oak trees by plot, but not proved in the relations by crown class. The cumulative growth, current annual increment and mean annual increment displayed various patterns by plot and by crown class in the heights, D. B. H. s and volumes of oak trees. The maximum values of current annual increment of height were generally recorded in 10 to 20 years, earlier than those of D. B. H. The mean annual increment of height, D. B. H. and volume maintained similar levels after about 10 years and fluctuated irregularly. The crown projection area and volume following to thinning decreased in the order of the thinning methods of grade A < grade B < crown thinning$90m^3/ha$ in about 40 years in the productivity of volume of the oak stand studied.

• Mycobiology
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• v.48 no.6
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• pp.484-494
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• 2020

Oak wilt disease caused by Raffaelea quercus-mongolicae has emerged obviously in Korea. We selected antifungal isolates against R. quercus-mongolicae among 368 endophytic fungal isolates from different parts of oak and pine trees. The experiment was conducted in the primary and secondary screenings by dual culture test. The antifungal activity of the selected isolates was assessed in culture filtrate test based on the inhibition rates in mycelial growth, sporulation, and spore germination of oak wilt fungus. Five isolates, E089, E199, E282, E409 and E415, showed strong antifungal activity in culture filtrate test, and their antifungal activity decreased on the culture media supplemented with heated culture filtrate. Higher mycelial growth inhibitions on the unheated media were recorded in E409 (Colletotrichum acutatum), E089 (Daldinia childiae), E415 (Alternaria alternata) and E199 (Daldinia childiae) with the inhibition rates of 79.0%, 70.1%, 68.9% and 64.5%, respectively. These isolates also had the higher sporulation inhibitions on unheated media with the rates of 96.8%, 84.2%, 82.8% and 80.5%, respectively. The spore germination of the oak wilt fungus was completely inhibited by E282 (Nectria balsamea) on both unheated and heated media. These results showed that a higher number of potent antifungal isolates against oak wilt fungus was isolated from the petiole compared to the other parts. This study could contribute to the development of biological control approaches for the management of oak wilt disease caused by R. quercus-mongolicae.

• The Plant Pathology Journal
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• v.16 no.5
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• pp.247-251
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• 2000

Latent infections of healthy-appearing oaks of Hypoxylon atropunctatum complicates field studies by interfering with inoculation experiments to follow pathogenesis, fungal development and reproduction of this canker rot fungus. Mutants with unique and easily scorable phenotypes would be useful for inoculation studies. There is a broad range in the capacity of wild-type isolates to utilize nitrate as a sole nitrogen sources. Several types of nitrate-nonutilization mutants (nit1, Nit3, NitM) were selected from nitrate-utilizing wild-type isolates. Also, a few mutants of Hypoxylon atropunctatum were selected that could only grow poorly on basal medium supplemented with various nitrogen sources and even on yeast extract agar. These unknown mutants need to be characterized further. Nit mutants of Hypoxylon atropunctatum were readily selected, grew well and were recovered after inoculation into oak stems. These results suggest that nit mutants could be useful for inoculation studies in trees that contain latent infections.

• Mycobiology
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• v.39 no.4
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• pp.313-316
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• 2011

The ambrosia beetle, Platypus koryoensis, is a serious pest of oak trees in Korea. In this study we investigated filamentous fungi present in the body of the beetle. Fourteen genera of filamentous fungi belonging to Ascomycota and Basidiomycota were isolated. Among the isolated fungi, some were able to produce wood degrading enzymes. This is first report of fungi associated with P. koryoensis.

• 한국균학회소식:학술대회논문집
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• 2014.05a
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• pp.41-41
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• 2014

Pinewood nematode (PWN, Bursaphelenchus xylophilus) is a serious pathogenic worm that quickly dry pine trees to death. Recently, PWN has been devastating huge amounts of conifer trees in Korea. As a first step to explore the association and ecological roles of fungi in PWN life cycle in Korea, in this study we first isolated and indentified fungi from PWN-infested Korean pine and Japanese black pine wood sampled in Jinju, Sacheon, Pocheon, Chuncheon, Gwangju, and Hoengseong in Korea. A total of 144 fungal isolates were obtained from Japanese black pine wood and 264 fungal isolates from Korean pine wood. Their morphology and nucleotide sequences of the ITS rDNA and ♌-tubulin gene were examined for species identification. Ophiostoma ips, Botrytis anthophila, Penicillium sp., Hypocrea lixii, Trichoderma atroviride, O. galeiforme, Fusarium proliferatum were identified from Japanese black pine wood. Leptographium koreanum, L. pini-densiflorae, Ophiostoma ips, Penicillium raistrick, Trichoderma sp. were isolated from Korean pine wood. O. ips and L. koreanum were the major species on the two different PWN-infected pine tree. The cultivation of PWN on fungal mat of the identified species did some enhance PWN reproduction. The ambrosia beetle, Platypus koryoensis, is a serious pest of oak trees in Korea. In this study we investigated filamentous fungi present in the body of the beetle. Fourteen genera of filamentous fungi belonging to Ascomycota and Basidiomycota were isolated. All the obtained genera were isolated in the mitosporic state. The identified fungi were classified in 11 distinct orders including the Ascomycota (Eurotiales, Hypocreales, Microascales, Ophiostomatales, Pleosporales, and Sordiales) and Basidiomycota (Agaricales, Corticiales, Polyporales, and Russulales Xylariales). Within Ascomycota, 13 species were found. Meanwhile five species were found within Basidiomycota. The results showed the presence of diverse fungi in P. koryoensis. Among the isolated fungi, some were able to produce wood degrading enzymes. Further fungal isolation was performed with P. koryoensis infested Quercus mongolica trees sampled at Kumdan mountain in Hanam-Si, Gyeonggi province from June of 2009 to June of 2010. Penicillin spp. and Trichoderma spp. were the major species of mold fungi group. Pichia guilliermondii was the major species of mold yeast group. Raffaelea quercus-mongolicae was also isolated, but its isolation frequency was not high. Other species identified were Ambrosiella xylebori, Fusarium solani, Cryphonectria nitschke, Chaetomium globosum, and Gliocladium viride, Candida kashinagacola, C. maritima, C. vanderkliftii, Saccharomycopsis crataegensis.

• Food Science of Animal Resources
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• v.18 no.4
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• pp.364-370
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• 1998

This study was carried out to establish optimum smoking conditions i.e., smoking temperature, time, and smoking material for meat products. Smoking materials employed for smoking were oak and apple trees. Roast ham and wiener produced by various smoking conditions wree subjected to polycyclic aromatic hydrocarbons (PAHs) analysis. Benzo(a)pyrene was not detected in roast ham and wiener prepared with oak wood smoked and apple wood smoked at 250$^{\circ}C$. The content of benzo(a)pyrene in roast ham and wiener with apple wood smoked at 400$^{\circ}C$ were 0.6 and 0.7 $\mu\textrm{g}$/kg, and those sample smoked at 500$^{\circ}C$ is not suitable for meat products due to the high production rate of benzo(a)pyrene. The higher smoking temperature of the products, the higher the content of PAHs. The similar tendency was observed in smoking time. PAHs contents of the products smoked with oak wood was ranged from non-dection to 0.5 $\mu\textrm{g}$/kg. Meat products smoked for 75 min. were found to be highly valuable from the viewpoints of flavour and color.

• Journal of Plant Biology
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• v.10 no.1_2
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• pp.36-40
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• 1967

1. The effect of the pH value on P32 absorption of leaves of three forest trees under the water culture is investigated. 2. The degree of the P32 absorption to the pH value is quite different in each forest tree. 3. The phosphorus contents are proved higher in the leaves of Quercus accutissima(the saw shaped oak) than in the leaves of Pinus densiflora(the red pine) and Lespedeza bicolar (bush clover). 4. Larger contents of phosphorus are found in acidity plots than in alkalinity. The leaves of treated plot of the pH 4 (red pine), of the pH 5.0 (bush clover), and of the pH 5.0-6.5 (saw shaped oak) have a higher nutrient capital as indicated by P32 compared with that of the other pH values. 5. It is also noticed that P32 absorption capacity is decreased with the higher pH values. 6. The content of P of leaves shows the lowest value in the plot of the pH 6.5 (pine), of the pH 7.5(bush clover), and of the pH 9.0(saw shaped oak). It is also noticed that the red pine is to do very well in acid cultivation and then follow bush clover and saw shaped oak in the order.

• Journal of Forest and Environmental Science
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• v.27 no.2
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• pp.113-118
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• 2011

This study was carried out to analyze annual diameter growth characteristics for major 11 tree species using the data for Gangwon province of the National Forest Resources Inventory in 2007. The annual diameter growth of coniferous species was 5.02 mm, 4.70 mm, and 3.90 mm in Korean white pine, Japanese larch, and Korean red pine, respectively. In growths of the deciduous trees, dogwood, basswood, and cork oak had 3.55 mm, 3.48 mm and 3.01 mm, respectively. Average of the annual diameter growths for all species was 3.38 mm. The relationship between diameter growth and age class showed that the growth rate decreased for all species as age increased. The age class II had the highest annual diameter rate. In relation of the stand density(trees per hectare) and diameter growth, the diameter growth tended to decrease as the stand density increased for most species, especially Korean white pine, cork oak, and basswood. Finally age had the highest value in the correlation coefficients between measurement factor and growth rate regardless of species.