Yes, CORKWOOD is a Scrabble word!

Letter values in Scrabble US: C 3, O 1, R 1, K 5, W 4, O 1, O 1, D 2.

Is it a valid word?

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

very small deciduous dioecious tree or shrub of damp habitats in southeastern United States having extremely light wood

Also: corkwood tree, leitneria floridana.