Large Live Trees. The large live trees of an old-growth forest not only stand testimony to the amount of time required to develop into old-growth but also largely determine the structure of the forest. The large trees in Muir Woods are the coastal redwoods, the tallest of all living things, and some scattered Douglas firs. The tallest coastal redwood at Muir Woods is about 258 feet, approximately the height of a six-foot person stacked head to toe 45 times. Further north, these trees can reach heights up to 379 feet, 74 feet taller than the Statue of Liberty. The average age of the coastal redwoods at Muir Woods is between 600 to 800 years, with the oldest being at least 1200 years old. This is still young for redwoods as they can live up to 2200 years. Being long-lived and large in size, they play a significant role in carbon, nutrient, and water cycling in the forest, helping to support an abundance of plant and animal life.