An analyst says the price of lumber will sink to as low as $350 by end of August.  Still, the industry will continue to face headwinds, especially when it comes to labor.  The price of lumber is trading at $642 per thousand board feet, roughly 62% lower from its May 7 peak.  North American lumber futures are sliding after a brief pop last week, falling 21% in the last five days as the hot commodity comes down from dizzying highs.  The price of lumber is trading at $642 per thousand board feet, roughly ...