Interestingly, there's even a color named after the color of dead leaves!
(FIL-mot) noun, adjective
The color of a dead or faded leaf: dull brown or yellowish brown.
An incarnadine color.
To make incarnadine.
Of a brownish-gray color; dusky.
[From Latin fuscus (dusky).]
1. Of a grayish or bluish green or white color.
2. Covered with a powdery coating of such colors, as on grapes, plums, etc.
[From Latin glaucus (bluish-gray or green), from Greek glaukos.]
(toap, rhymes with rope) noun
A brownish gray, similar to the color of moleskin.
[From French taupe (mole), from Latin talpa.]