top

Shiro TSUYUZAKI
Plant community ecology / Environmental conservation

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

(Update on Sept. 15 2008. Revise on Nov. 5 2009)

Prickly lettuce
Lactuca scariola L. [Asteraceae]

Togechisya (トゲチシャ, 刺萬苣)

Life form: annual - biennial forb
Distribution: widespread weed in cool to tropical regions (exotic to Japan)
Habitat: sunny sites, e.g., crop field, waste ground, roadside verge
Chromosome number: 2n = 18

Synonyms

Lactuca serriola L. (the standard)

Varieties

f. integrifolia (Bogenh.) G. Beck. (マルバトゲチシャ): leaves non-laciniated


Lactuca scariola in Hokkaido

ST1 ST2
ST3 ST4
[1] A whole plant. [2] Close-up to inflorescences. [3] Leaves (f. integrifolia). This species has dimorphic leaves. [4] leaves of the type. Compare to [3]. [1/4] At N25/W1, West Ward, Sapporo, on July 28 and August 1 2011, respectively. [2/3] At a parking lot along a radoside at West Ward, Sapporo, on August 30 2008.


References

TOP