The Erechthites hieracifolia. It is not properly a grass.

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1792.  The fire-weed, which spontaneously grows on all burnt land. This fire-weed is an annual plant, with a succulent stalk and long jagged leaf; it grows to the height of five or six feet…. It … never vegetates, except on the ashes of burnt wood.—Jeremy Belknap, ‘New Hampshire,’ iii. 133–4. (Partly cited, N.E.D.)

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1821.  Immediately after the fires, a species of grass springs up, sometimes called fire grass, because it usually succeeds a conflagration.—T. Dwight, ‘Travels,’ iv. 61.

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1857.  There were great fields of fire-weed (Epilobium angustifolium) on all sides, which presented great masses of pink.—H. D. Thoreau, ‘The Maine Woods,’ p. 262 (1864).

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