Flavescent describes something that is yellow or yellowish, or that is turning yellow, such as the leaves of aspen and birch trees in the fall.
The word flavescent comes from the Latin word flavus, meaning "yellow." It can be used to describe something that is yellow or yellowish. For example, adding saffron to rice makes the rice turn distinctly flavescent. But it's more often used to describe the process of becoming yellow, such as ripening grain, aging photographs, or the colors of a sunset.