Bark is an essential aspect of any tree, protecting the delicate flow of life up and down the thin cambium layer that lies just under it, between the bark and the wood.  A branch flute aught to honor and include that important aspect of the tree, if it can.  In this Arroyo Willow (Salix lasiolepis) branch flute, much of the bark has been left on, though sanded smooth, down to it's coffee colored layer, providing a nice contrast to the lighter colored and finely finished wood grain.  Measuring 20 1/4" in length, with four tuning holes, it is tuned to a clear and bright, mid-range G# pentatonic scale, playing three upper octave notes and a wonderfully passionate "warble" on the fundamental, as heard in the sound sample.  A few small knot holes and tiny surface checks have been inlaid with malachite.  Elk lacing with malachite and horn bone beads holds the bird to the nest, the bird fitted with a redwood shoe to aid against wetout.  The branch for this flute was gathered sustainably, with love, respect and gratitude, along San Marcos Creek, in San Diego County, CA amongst a wild grove of Arroyo Willow trees.   California Indians found many uses for the wonderful willow tree, including bows, baskets, shelters, clothing, fish traps and medicines derived from salicin in the willow's bark, the original aspirin.