• Journal of Environmental Science International
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• v.15 no.12
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• pp.1119-1124
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• 2006

Height-growth analysis was used to examine forest structure and compare Pterocarya rhoifolia and Fraxinus spaethiana growth characteristics within and between each species in two P. rhoifolia-dominant and two F. spaethiana established contemporaneously in the sere, species vertical stratification 25 years after stand initiation was such that P. rhoifolia dominated the overstory but F. spaethiana the understory, including that P. rhoifolia grew about 4 times more rapidly Similarly, F. spaethiana dominated the overstory but not the understory, in a stand where it established mainly by itself, 25 years after Initiation. However, comparing the two different stands, P. rhoifolia overstory heights were about two times greater than F. spaethiana. This suggests that in a disturbance regime, forest regeneration is affected by height-growth patterns such that P. rhoifolia's ability to achieverapid height growth allows it to dominate where lights growth allows it to dominate where light resources are continuously abundant.

• Journal of Forest and Environmental Science
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• v.24 no.3
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• pp.127-135
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• 2008

The mission of the Forest Inventory and Analyis (FIA) program of the Forest Service, U.S. Department of Agriculture, is to conduct the national forest inventory of the United States of America for purposes of estimating the area of forest land; the volume, growth, and removal of forest resources; and the health of the forest. Users of FIA data, estimates, and related products include land managers, policy and decision-makers, forest industry, environmental organizations, and university researchers. To accomplish its mission, the FIA program has established a sampling design with an intensity of approximately one permanent plot per 2,400 ha across the entire country. Depending on the region of the country, each plot is remeasured at intervals of five or 10 years. The program releases data annually and reports estimates at the county level for each state every five years. Due to budgetary constraints and natural variability among plot observations, sufficient numbers of plots cannot be measured to satisfy precision guidelines for the estimates of many variables unless the estimation process is enhanced using ancillary data. Classified satellite imagery has been demonstrated to be a source of ancillary data that can be used with stratified estimation techniques to increase the precision of estimates with little corresponding increase in costs. A crucial factor restricting the utility of FIA data is that the exact locations of inventory plots cannot be released to the public. Thus, users are generally not able to obtain estimates for small areas or for their own areas of interest if exact plot locations are required. To compensate, satellite imagery, inventory plot data, and the k-Nearest Neighbors technique are being used to construct Internet-based maps of forest attributes from which estimates for arbitrary user-defined areas of interest may be obtained.

• Horticultural Science & Technology
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• v.34 no.3
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• pp.372-382
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• 2016

In this study, we investigated the effect of seed collection stage and alternating temperature on the germination of Deutzia paniculata (Hydrangeaceae). The seeds were collected from naturally growing D. paniculata populations in Mt. Palgong, Gyeonsangbuk-do, Korea every two weeks over a three month period from August through October, 2014, totaling five collections. We examined seed characteristics such as seed size (length and width) and weight, and germination percentages for each collection stage under four different germination temperature regimes. We also examined germination after 30 and 60 days of cold moist stratification. Each collection phase had a different germination percentage and the lowest germination percentage was observed in the seeds from phase I (average GP of 15.7%). The germination percentage was similar at the later collection phases and in the higher temperatures suggesting that later collection times and higher temperatures are optimal for D. paniculata germination. We found that the optimum collection stage with high viability and germination percentage of for D. paniculata was during the middle of the September.

• Korean Journal of Plant Resources
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• v.19 no.5
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• pp.580-585
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• 2006

This experiment was conducted to study the effects of sulphuric acid, cutting, cold stratification and hot water on the germination of Sophora japonica seeds, which have difficulty to germinate because they have hard and thick seed coats. The seeds were immersed in 30, 60 and 90% sulphuric acid for 30 minutes as seed scarifications, and cut 1/8, 2/8 and 3/8 of the opposite parts of radicles. As cold stratification the seeds were wrapped in wet towel, and then stored in plastic bags in a refrigerator $(4^{\circ}C)$ for 3, 5 and 10 days. The seeds were immersed in hot water $(90{\sim}95^{\circ}C)$ for 2,5 and 10 minutes. Pretreated seeds represented different germination properties, respectively. After sulphuric acid treatment, the seeds showed an increase in germination (G) and germination index (GI). Compared to the other treatments, 90% sulphuric acid showed the highest G (31.7%) and GI (6.2). The G and GI of cut seeds decreased with the increase of seed cutting lengths. And G and GI of cold stratificated seeds were not significantly different among the days treated (p=0.258). Two minutes treatment of hot water showed lower G and Gl than control, and the seeds were not germinated in 5 and 10 minutes treatments of hot water. At the result of relative growth rate and T/R ratio of seedlings from pretreated seeds, the seedlings from seeds in 90% sulphuric acid treatment represented the highest relative growth rate and T/R ratio.

• Journal of Korean Society of Forest Science
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• v.28 no.1
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• pp.21-30
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• 1975

The purpose of this paper is to elucidate physiologically the cause of the hastening germination of dormant Taxus cuspidata seeds by stratification. During the stratification the exchange of chemical substances such as sugar, protein, starch and fat were observed, and growth promoting and inhibiting substances were extracted and seperated from seeds by the conventional chromatographic method with coleoptile straight-growth test. An intensive investigation was made on the balance between the promoters and inhibitors. consequently, it was confirmed that germination of seeds was accelerated with exchange of chemical substances by stratification. The results obtained may be summarized as follows: 1. During the stratification growth promoters were increased and growth inhibitors were decreased rapidly in the endosperm of seeds. Thus, it was presumed that hastening germination was controlled by balace between the promoters and inhibitors from November to next March after a year's stratification. On the other hand growth promoters were almost constant and growth inhibitors were decreased rapidly in the seed coats, and it was presumed that hastening germination was influenced by exchange of inhibitors more than by that of promoters. 2. As a results of germination test of lettuce seeds, it was generalized that hastening germination was controlled by a decreased amount of growth inhibitors more than by an increased amount of promoters. 3. During the stratification sugar and crude protein contents were increased gradully with moisture content, while starch and crude fat were decreased in endosperm of seeds. So it was assumed that the exchange of these chemical substances was closely related to the germination of seeds.

• Journal of Korean Society of Forest Science
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• v.78 no.1
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• pp.26-29
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• 1989

To seek for a proper pretreatment method for increasing field germination rate, field germination rate of 5 tree species including Phellodendron amurense was investigated and was compared among pretreatment methods. The results obtained in this study were as follows ; 1. Field germination rates of Poncirus trifoliata and Fraxinus rhynchophylla among pretreatment methods were significantly different at 1% level, and that of Phellodendron amurense among pretreatment methods were significantly different at 5% level. In thses species, highest field germination rate was observed on the plot of cold moist stratification under the ground (Nochunmaejang ; during 166 days). 2. Field germination rates of Chaenomeles sinensis among pretreatment methods were significantly different at 1% level, and highest field germination rate was observed on the plot of cold moist stratification in the refrigerator (during 110days). 3. Field germination rates of Cudrania tricuspidata among pretreatment methods were not significantly different at 5% level.

• Journal of Korean Society of Forest Science
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• v.63 no.1
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• pp.9-11
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• 1984

This study was carried out to compare the seed germination and seedling growth of Fraxinus mandshurica growing in natural forests of the interior of Korea. Three stimulation methods were used for germination and the seedlings were planted with various densities. The results obtained were summarized as follows: 1) It was suggested that the 80 seedlings per square meter were proper densities for their growth at a nursery bed. 2) Among the three stimulation methods, 19.9% of germination was shown by the moisture storage, 2.3% by cold and warm stratification, and 0.4% by cold stratification. 3) The 8.1% of the total seedlings showed secondary height growth.

• Journal of Korean Society of Forest Science
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• v.99 no.3
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• pp.285-291
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• 2010

Since 2006, the $5^{th}$ National Forest Inventory (NFI) has been implemented to provide forest resources statistics at the national level and at the county level as well. However, it needs a small-area estimator for estimating forest statistics at the county-level due to a small number of samples collected within a county. This study was conducted to evaluate the applicability of a geographical-based synthetic estimator for estimating forest growing stock volumes at the county level. The NFI-field plots surveyed were post-stratified into three forest cover types. In the synthetic estimator, field plots within a geographical-based super-county for each county were used to estimate stratum weights and stratum mean volumes. It was resulted that estimated stratum weights using the synthetic estimation were significantly differ from forest cover maps. The standard errors of estimated mean by the synthetic estimation that ranged from ${\pm}3.5\;m^3$/ha to ${\pm}7.7\;m^3$/ha were more smaller than those (${\pm}7.8\;m^3/ha{\sim}{\pm}24.7\;m^3/ha$) by the direct estimation. This means that the synthetic estimation is possible to provide more precise estimates of mean volumes.

• Journal of Korean Society of Forest Science
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• v.86 no.4
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• pp.443-449
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• 1997

We examined the effect of pretreatments on seed germination, seedling growth, optimal seedling density of Phellodendron amurense. The seeds were carefully purified after collection in late Oct. from natural population at Mt. Chiri. For the evaluation of pretreatment effects, seeds were sowed in an experimental nursery after being stored in open ground($2{\sim}8^{\circ}C$) with soaking in 20% $H_2O_2$, 50-fold pon-pon solution, cold moist stratification in refrigerator($2{\sim}4^{\circ}C$) and dry storage in roam temperature($4{\sim}18^{\circ}C$), respectively, For the effect of growth density of seedlings, seedlings germinated in nursery were precisely controlled with 53, 104, 220, 380 seedlings per $m^2$. Among pretreatments for the promotion of germination rate, pon-pon treatment(68.8%) was highest, the others were higher than that in dry storage(2.3%), and these seed pretreatment methods were significantly different at 1% level. The height growth of seedlings showed the most vigor from Jun.12 to Jul. 8, and from Jul.20 to Aug. 2, and it reached to 72.8% of height growth. In case of 1-0 seedling, although seedling density per $m^2$ was increased, seedling growth was decreased. The optimal seedling density was 104 seedlings per $m^2$. The standard seedlings for plantation were above height 55cm, root collar diameter 8.1mm, and root length 21cm. These results demonstrated that seed of P. amurense requires stratification for the germination promotion.

• Journal of Plant Biotechnology
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• v.7 no.1
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• pp.75-80
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• 2005

Eleutherococcus senticosus (also called Acanthopanax senticosus), belonging to Araliaceae family, has been used as an important medicinal woody plant. Mature seeds of Eleutherococcus senticosus have rudimentary (extremely immature) zygotic embryos and require a long-term stratification for about 18 months to induce germination. Here, through the methods of endosperm removal and other exogenous treatments, we investigated the factors for inducing rudimentary embryos by in vitro culture, Rudimentary zygotic embryos in seeds were at globular to heart-shaped stage at about $250{\mu}m$ in length just after harvest of fruits. When the seeds without testa were cultured on 1/2 MS (Murashige and Skoog 1962) medium, they did not germinate regardless of medium and sucrose concentrations but the removal of endosperm tissue markedly stimulated the growth of rudimentary zygotic embryos. The embryo reached ear-lier maturation, once when the endosperm surrounding the rudimentary embryos was removed. Rudimentary zygotic embryos developed cotyledons within 3 weeks of culture after endosperm emoval. However, post-mature zygotic embryos failed to germinate though they were morphologically normal, indicating another dormancy of embryos. $GA_3\;(2.0\;\cal{mg/L})$ and/or charcoal ($0.2\%$) treatment rapidly enhanced the germination of zygotic embryos. These results suggest that E. senticosus seeds have double dormancy; i. e. morphological rudimentary dormancy influenced by surrounding endosperm and physiological dormancy after post-maturation of zygotic embryos. Based on the above findings, we established the rapid germination of rudimentary zygotic embryos by in vitro culture of excised seeds with endosperm removal and $GA_3$ treatment.