From A History of the English Language

He [the American] is perhaps at his best when inventing simple homely words like apple butter, sidewalk, and lightning rod, spelling bee and crazy quilt, low-down, and know-nothing, or when striking off a terse metaphor like log rolling, wire pulling, to have an ax to grind, to be on the fence.... The American early manifested the gift, which continues to show, of the imaginative, slightly humorous phrase.  To it we owe to bark up the wrong tree, to face the music, fly off the handle, go on the warpath, bury the hatchet, come out of the little end of the horn, saw wood, and many more, with the breath of the country and sometimes the frontier about them.  In this way, the American began his contributions to the English language.