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Shiro TSUYUZAKI
Plant community ecology / Environmental conservation

Mount Usu / Sarobetsu post-mined peatland
From left: Crater basin in 1986 and 2006. Cottongrass / Daylily

(First update on June 14 2003. Last on September 8 2010)

Bitter-dock (Broad-leaved-dock)
Rumex obtusifolius L. [Polygonaceae]

Ezo-nogishigishi (エゾノギシギシ, 蝦夷ノ羊蹄)

Lifeform: deciduous forb
Distribution: native to Europe, now widespread exotic weed in Japan
Habitat: disturbed sites, including pastures


Rumex obtusifolius on Mount Usu

Gully1 SB2 SB3 SB4
1 These plants were originated from seedbank in the former topsoil.

Seeds extracted from the former topsoil

Seed germination method

2 Seedlings emerged from the former topsoil collected in September. The photo was taken on December 24 2008. The experiment was conducted in the greenhosue of Center of Advanced Science and Technology (CAST), HU.

Seed flotation method

3/4 R. obtusifolius seeds, extracted by a centrifuged floation method, in the fall of 2008, 30 years after the 1977-78 eruptions. (refer to Tsuyuzaki & Goto 2001)


Rumex obtusifolius in Hokkaido

ST ST ST
[Left] a plant. [Center] close-up of inflorescences. [L/C] At Toya Lake Experimental Station, Hokkaido Univ., on September 8 2009. [Right] fruits. at Muroran Marine Experimental Station, HU, on August 23 2010.


References

  • Tsuyuzaki, S. 2010. Seed survival for three decades under thick tephra. Seed Science Research 20: 201-207
  • Tsuyuzaki, S. & Goto, M. 2001. Persistence of seedbank under thick volcanic deposits twenty years after eruptions of Mount Usu, Hokkaido Island, Japan. American Journal of Botany 88: 1813-1817
  • タデ科 Polygonaceae
  • Rumex acetosella
  • seed germination
  • weed

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