Giant Sequoia stats - Oldest : Muir Snag (Converse Basin Grove) 3.500+ years. Tallest : Unnamed tree (Redwood Mountain Grove) 311 feet. Greatest girth : Waterfall tree (Alder Creek Grove) 155 feet - tree with enormous basal buttress on very steep ground. Largest, by volume : the General Sherman (Giant Forest) : height 274.9 ft, girth of 102.6 ft, estimated weight 2100 tonnes. (All of these trees are in California).