About a million cord of old-growth timber—yellow birch, red oak, pine—is thought to lie at the bottom of northern Maine lakes and rivers, lost during logging operations a century ago. Now it’s being reclaimed for interior millwork, including flooring ($9.50 to $14 per square foot), millwood ($3 to $5 per square foot), and wainscoting ($90 for 25 square feet). Maine Heritage Timber, 207.723.9200, maineheritagetimber.com