Giant Sequoias and Redwoods are not the same thing actually they are to completely different trees the Redwood being taller and the Sequoia being tall but MUCH thicker. The Sequoia not only has Fire Retardent bark but also it has the ability to fight of funguses that often kill smaller trees. The Sequoia is not the thickest (Sabino) or Tallest (Redwood) but its the largest in terms of Volume