Actually, one needs to measure and photograph them to understand the size. Tapes and lasers almost always tell the truth, and skillful photography can capture size and details exceeding the sense of sight of 10 people combined. There's nothing quite like standing there in person to engage all 5 senses though.
Very close to us, near Orick and Crescent City, CA, are coast redwoods which are both the widest and tallest trees in all 50 states, even exceeding Sequoiadendron from girth. I enjoy both species and visit both regions.