Yes, HORSEBEANS is a Scrabble word!

Letter values in Scrabble US: H 4, O 1, R 1, S 1, E 1, B 3, E 1, A 1, N 1, S 1.

Is it a valid word?

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

seed of the broad-bean plant
large shrub or shrubby tree having sharp spines and pinnate leaves with small deciduous leaflets and sweet-scented racemose yellow-orange flowers; grown as ornamentals or hedging or emergency food for livestock; tropical America but naturalized in southern United States

Also: broad bean, fava bean, jerusalem thorn, parkinsonia aculeata.