Yes, FLAXES is a Scrabble word!

Letter values in Scrabble US: F 4, L 1, A 1, X 8, E 1, S 1.

Is it a valid word?

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

fiber of the flax plant that is made into thread and woven into linen fabric
plant of the genus Linum that is cultivated for its seeds and for the fibers of its stem