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"Sooo, birdhouses these days are made from a variety of materials: plastic, recycled plastic, composite, wood, reclaimed wood, recycled milk jugs, you get the picture. And, oftentimes birdhouses today come with upgrades and new gadgets,"^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.treehugger.com/natural-sciences/solar-birdhouse-giving-birds-the-edge-over-mother-nature.html>