When is the bark of the redwood trees and sequoias thickiest?

The bark of redwood trees and giant sequoias is thickest in mature trees, typically reaching its maximum thickness as they age, around 1 to 3 feet thick. This thick bark develops over many decades and serves as an essential defense against fire, pests, and diseases. The thickness varies by species and environmental conditions, but it generally increases as the trees grow older and larger.