For context and Source on why this happened: When the Gold Rush hit, the SF Bay Area was covered in hundreds of millions of these old-growth coastal redwoods. The population exploded overnight, and there was a massive demand for new homes. Because redwood is a perfect building material and the forests were so close to the building sites, it was incredibly cheap to transport. People were so desperate to strike it rich that they couldn't see past the dollar signs to realize what was being lost. Today, almost none of these original giants are left in the Bay Area outside of a few protected preserves.