Yes, RHUSES is a Scrabble word!

Letter values in Scrabble US: R 1, H 4, U 1, S 1, E 1, S 1.

Is it a valid word?

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

deciduous or evergreen shrubs and shrubby trees of temperate and subtropical North America, South Africa, eastern Asia and northeastern Australia; usually limited to nonpoisonous sumacs (see genus Toxicodendron)

Also: genus rhus.