in Thoreau’s Journal:

Most leaves are already somewhat faded and withered. Their tints are not so bright. The chestnut leaves already rustle with a great noise as you walk through the woods, as they lie light, firm, and crisp. Now the chestnuts are rattling out. The burs are gaping and showing the plump nuts. They fill the ruts in the road, and are abundant amid the fallen leaves in the midst of the wood. The jays scream, and the red squirrels scold, while you are clubbing and shaking the trees.  Now it is true autumn—all things are crisp & ripe.