At Holden Swamp

October 13. 

Now, as soon as the frost strips the maples, and their leaves strew the swamp floor and conceal the pools, the note of the chickadee sounds cheerfully winteryish.

H. D. Thoreau, Journal, October 13, 1860

Leaves strew the swamp floor and conceal the pools. See October 12, 1855 (“The leaves fallen last night now lie thick on the water next the shore, concealing it, —fleets of dry boats, blown with a rustling sound”)

The note of the chickadee sounds cheerfully winteryish. See October 13, 1852 ("It is a clear, warm, rather Indian-summer day. . . we welcome and appreciate it all. The chickadees take heart, too, and sing above these warm rocks.")  See also  October 10, 1851 ("The chickadee, sounding all alone, now that birds are getting scarce,reminds me of the winter, in which it almost alone is heard.”); October 11, 1859 ("The note of the chickadee, heard now in cooler weather and above many fallen leaves, has a new significance.");  October 15, 1856 (“The chickadees . . .resume their winter ways before the winter comes.”)