Most timbers show variation in colour between species and within species. Colour descriptions usually relate to the heartwood of the species and may be significantly different from that of the sapwood.
Colour may also vary in use and by the application of finishes.
Timber exposed to light will change colour and unprotected timber, exposed to the weather, will eventually become silvery grey.
NAFI Timber Manual: Timber Datafile P1 – Timber Species and Properties.