UPDATE: Experts say the original estimate of the tree as more than 300 years old (made by a University of Louisville biology professor) is very inaccurate. This story's headline has been changed to reflect the new information. Click here for an update to the story.Original post:A 309-year-old oak tree has been cut down to make room for the Speed Art Museum’s expansion. The Valley oak (Quercus lobata) was cut down sometime late last year in preparation for construction of the new $50 million project, which will triple the Speed’s gallery space.U of L student Wesley Kerrick seems to be the first to have noticed the tree’s absence. In an opinion piece in the Louisville Cardinal published last week, he talks about coming back to campus in January and finding the tree’s stump. In this case at the Speed Museum, a scientific specimen, an object of permanent value was obliterated, erased from memory without any evident hint of remorse. Granted, it’s an art museum, not a tree museum. But aren’t trees art? Didn’t standing by that tree help us recognize our relative insignificance in the grand scheme of the earth’s history? Didn’t it stand as a monument to the Native Americans who lived here before us, and as a reminder to practice sustainability? …. I’m sure the expanded museum will be a spectacular contribution to U of L and Louisville. But when a museum seems to hold no regard for objects of value, it leaves me scratching my head.The story was also picked up by Louisville native Branden Klayko, blogging at The Architect’s Newspaper.According to an app developed by Urban Wildlife Research Lab Director Tommy Parker, the Valley oak was 309 years old and nearly 60 feet tall. It absorbed 116.75 pounds of carbon dioxide every year, and carbon dioxide is a greenhouse gas that contributes to climate change.The Valley oak wasn't the oldest tree on campus--that title went to a 375-year-old Shumard oak--but it was still significant.But when I called the Speed Museum to check into the tree's removal, no one could tell what tree I was talking about. Spokesman Steven Bowling said the only oak tree that was cut down for the expansion was only about 50 years old. (Update: The debate continues) But when I called Parker to ask about the tree, he didn't equivocate. "Oh, that tree is gone."So I met Bowling and Parker, as well as Speed Director of Operations and Expansion Greg Gardiner at the site to settle the dispute. It turns out everyone was talking about the same tree, and the Speed did, in fact, cut down a 300+ year old Valley oak.Looking at the stump, only about 50 tree rings are visible, which is the main reason for the Speed's confusion about which tree Parker was talking about."Well the rings are so close together," Parker said. "As a tree gets older the rings get pushed tighter together. So you'll need to look under a special dissecting microscope to see the actual splits between the rings."Bowling says it's unfortunate that the tree had to be removed, but the museum's expansion will provide opportunities to seamlessly integrate art and nature.The loss of the tree comes at a time when Louisville is trying to figure out how to plant more trees to combat the urban heat island effect, which is warming the city. Mayor Greg Fischer's sustainability plan has called for 10,000 new trees by 2020 to offset trees lost during ice storms and from disease, but that number doesn't take into account the trees like this Valley oak that have been purposely removed. Mature trees absorb more carbon dioxide, and Parker estimates it would take 35 new 2-inch diameter trees to absorb the same amount of carbon dioxide as U of L's Valley oak tree did. "You hate to see it go down," Parker said, but he understands why the tree had to be removed: it was right in the middle of where the museum's expansion will sit. Now, the Speed is going to give a cross-section of the Valley oak to Parker and his students, so they can examine it under a microscope and learn from it.The story is updated here.