One of the real features of the Jeju autumn landscape is eulalia, a kind of flowering grass. Hillsides are covered with it, it grows on verges and areas of uncultivated land. When the sun catches it, it can be a quite a sight.
The top photo was taken a couple of weeks ago on the west coast. The photo below was taken from the foot of Mt Dan, with Sanbangsan in the background.
Notes from a Korean island 