The Planeteers travel to the Northwest after hearing about an old growth forest which is, literally, disappearing into thin air. After Wheeler goes off to investigate with a pretty local teenage bird watcher, Linka spots a "flying saucer" but Kwame recognizes the pilot . . . Hoggish Greedly! They discover Greedly's scam - "Sucking up" 500-year-old trees to make pressed board furniture. Outraged, they try to stop him, but his "Tree Trasher" may be too much for them.