Redwoods have no 'tap' root, rather their root system is a circle, out from the 'mother' tree--creating a family of next-generation trees--growing to 'logging' size in 20 years but if left alone, continuing to grow for hundreds of years--even thousands--older even than the dinosaurs, these trees have survived and, if left alone, will continue to do so--man is their greatest threat, thus we thank John Muir for his foresight in setting aside these giants for us to see and marvel about.