Yes, AGUEWEED is a Scrabble word!

Letter values in Scrabble US: A 1, G 2, U 1, E 1, W 4, E 1, E 1, D 2.

Is it a valid word?

AGUEWEED is a valid word in the official Scrabble dictionary (US), the UK Scrabble Dictionary and Words with Friends (ENABLE).

gentian of eastern North America having clusters of bristly blue flowers
perennial herb of southeastern United States having white-rayed flower heads; formerly used as in folk medicine

Also: ague weed, five-flowered gentian, stiff gentian, gentianella quinquefolia, gentiana quinquefolia, eupatorium perfoliatum.