• Title/Summary/Keyword: light control

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Principal Characteristics of Pinus parviflora S. et Z. Native to the Dagelet Island (울릉도(鬱陵島) 섬잣나무의 특성(特性)에 관(關)한 연구(硏究))

  • Ahn, Kun Yong
    • Journal of Korean Society of Forest Science
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    • v.12 no.1
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    • pp.31-43
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    • 1971
  • In order to examine the taxonomic difference between the type of Pinus parviflora S. et Z. native to the Dagelet Island and the type of the species introduced to a number of places of the inland of South Korea, investigations on principal characters of needle, cone and seed were made with a hope to obtain informations on the evaluation of the species for possible use in the reforestation program in Korea in the future. Pinus parviflora is belonged to the Sub-genus Haploxylon of Genus Pinus and it has been speculated among dendrologists that this speoies is not monotypic. 308 rendomly selected trees from 8 different elevations of a natural stand of P. parviflora in the Dagelet Island, and 168 trees of P. parviflora growing at 15 different locations of the inland of South Korea were employed as samples along with 300 trees of P. koraiensis as control. The results obtained are summarized as follows: 1. The needle length of the Pinus parviflora of the Dagelet Island is longer than that of the species growing in the inland by 21-35 percent with statistical significancy. (Table 2) 2. In the cross section of needle, no resin canal was observed in about 50-70 percent of the sample trees of the Dagelet Island, whereas the resin canals appearing at external in most cases were observed in all sample trees from the inland. Consequently, the number of resin canals per needle was 0.4-0.9 with the Dagelet Island type and 2.0-2.7 with the inland type and these differences were statistically significant. (Table 3, Fig.2) 3. The Pinus parvviflora type of the Dagelet Island bas yellowish brown cones, and the Pinus parviflora type of Suwon and Kwangyang has redish brown cones. In both the length of cone and the number of cone scale, the difference between the type of the Dagelet Island and the type of the inland was also statistically significant. The cone scales of the Dagelet Island type are slightly opened, whereas the cone scales are widely opened with both of Suwon and Kwangyang type. (Table 4, Fig. 3) 4. the seed color, of the Dagelet Island type is yellowish brown, while it is greyish brown with Kwangyang and Suwon type. In the length and width of seed, the Dagelet Island type showed significantly larger values than that of the inland type. The length of seed was longest with the Kwangyang type being followed by Suwon and the Dagelet Island type in ordar. The seed wing of the Kwangyang type are longer than the seed, while that of the Dagelet Island type is degenerated to be shorter than the seed. (Table 5, Fig. 4) 5. The Pinus parviflora type of the Dagelat Island is similar in many respects to the southern type of Pinus parviflora of Japan except that many has no resin canals in the needle. 6. On the basis of the results obtained in this study, it may be concluded that the type of Pinus parviflora of the Dagelet Island is significantly different from the type of the species introduced to the inland and that there is no recognizable variation between the population of the different altitude of the Dagelet Island and the individual variation within population is also negligible. In the light of the high value of the tree not only as an ornamental tree but as an economical tree, The type of Pinus parviflora of the Dagelet Island is considered to be recommendable to be used for the future reforestation program of Korea.

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