Yes, AMARELLE is a Scrabble word!

Letter values in Scrabble US: A 1, M 3, A 1, R 1, E 1, L 1, L 1, E 1.

Is it a valid word?

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

any of several cultivated sour cherry trees bearing pale red fruit with colorless juice
pale red sour cherry with colorless or nearly colorless juice

Also: prunus cerasus caproniana.