Colobanthus kerguelensisHook.f.

Family:Caryophyllaceae

Description:perennial herb that forms loose clumps or cushions up to 65 mm in diameter. The slender, freely branching stems lack adventitious roots

Habitat:gravel substrates in the supralittoral or sea spray zone, in well-drained peaty and sandy soils with Azorella selago, and in feldmark, up to elevations of 30 m above sea level.[2] It is a pioneer coloniser of recently deglaciated areas

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More info about cushion types

Colobanthus kerguelensis