Flute Quartet - 3 flutes and Alto Flute. Toppling Leaves is in a modern jazz style.
A chorale-like introduction using modern harmonies leads into solo-like sections where flute 1 has a free line over ostinati in the lower three parts, interspersed with short interjections in rhythmic unison.
There then follow sections where the top three parts build up to a climactic finish. Wandering through many keys (including Ab major), and using some complex rhythmic patterns, this is a treat for a more advanced quartet.