Somewhere in this neighborhood we traversed a pine wood, in which my first Walden pine warbler was trilling.
And even so simple and definite a thing as the pine warbler's song may be varied by the individual singer from time to time.
Whereupon the pine warbler sang again, the same trill but with a tittering twang about it that just jocosely imitated the flicker.
It comes with the yellow palm warbler late in April, when many of the trees are nearly bare, and not long after the pine warbler.
The bluebird's warble and the pine warbler's trill could never be disturbing to the quietest mood.