That is a wonderful description, one who knows that call/song can easily imagine the feeling of a natural cathedral in the shadow of those trees on a quiet day. Of course thrushes are legendary for the ability to turn a wood into a place of wonder, Wood thrushes in the East!, Veerys after a rain, and Swainson's thrushes in the west. Varied's spend the winter here actually summer too but at extreme elevations, and continue to call through the winter, wondrous multiple pitched harmonic whistles. Each true to the note it was started on. Even the song of our American robin from a treetop on a spring evening. Interestingly Robins do sing in the winter sometimes in a soft whispery voice, like humming, and many bleak winter day has been transformed into the hope of spring by the sound of this coming from a leafless tree with a huddled up robin sitting there
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