I see a little silhouetto of a tree. Is this real life? Is this just fantasy? Nah, it’s real. Though the twisted, spiky Joshua trees (Yucca brevifolia) look like something straight out of a Dr. Seuss book, they are quite real. There’s even a national park named for them. Hint: It’s @joshuatreenps. (You were thinking Redwood or Sequoia?) But is it actually a tree? It’s actually a giant yucca, in the Agave subfamily. Judging the age of a Joshua tree is challenging (you don’t want to be rude): these “trees” do not have growth rings like you would find in an oak or pine, but you can make a rough estimate based on height, as Joshua trees grow at rates of one-half inch to three inches per year. Some researchers think an average lifespan for a Joshua tree is about 150 years, but some of the largest trees in the park may be much older. The Joshua tree is an important part of the Mojave Desert ecosystem, providing habitat for numerous birds, mammals, insects, and lizards. Joshua tree fore...